Scholars@Duke
K. V. Rajagopalan

K. V. Rajagopalan

James B. Duke Distinguished Professor Emeritus of Medicine
Biochemistry
raj@biochem.duke.edu
Box 3711 Med Ctr, Durham, NC 27710
225A Nanaline H Duke, Durham, NC 27708

Scholarly Works - Journal articles

The role of tyrosine 343 in substrate binding and catalysis by human sulfite oxidase.

Journal article J Biol Chem · April 9, 2004 Featured Publication In the crystal structure of chicken sulfite oxidase, the residue Tyr(322) (Tyr(343) in human sulfite oxidase) was found to directly interact with a bound sulfate molecule and was proposed to have an important role in mediating the substrate specificity and ... Full text Link to item Cite

Essential role of conserved arginine 160 in intramolecular electron transfer in human sulfite oxidase.

Journal article Biochemistry · October 28, 2003 Featured Publication Arginine 160 in human sulfite oxidase (SO) is conserved in all SO species sequenced to date. Previous steady-state kinetic studies of the R160Q human SO mutant showed a remarkable decrease in k(cat)/K(m)(sulfite) of nearly 1000-fold, which suggests that Ar ... Full text Link to item Cite

Mechanistic studies of human molybdopterin synthase reaction and characterization of mutants identified in group B patients of molybdenum cofactor deficiency.

Journal article J Biol Chem · July 11, 2003 Featured Publication Biosynthesis of the molybdenum cofactor involves the initial formation of precursor Z, its subsequent conversion to molybdopterin (MPT) by MPT synthase, and attachment of molybdenum to the dithiolene moiety of MPT. The sulfur used for the formation of the ... Full text Link to item Cite

The 1.2 A structure of the human sulfite oxidase cytochrome b(5) domain.

Journal article Acta Crystallogr D Biol Crystallogr · July 2003 Featured Publication The molybdenum- and iron-containing enzyme sulfite oxidase catalyzes the physiologically vital oxidation of sulfite to sulfate. Sulfite oxidase contains three domains: an N-terminal cytochrome b(5) domain, a central domain harboring the molybdenum cofactor ... Full text Link to item Cite

Recombinant Rhodobacter capsulatus xanthine dehydrogenase, a useful model system for the characterization of protein variants leading to xanthinuria I in humans.

Journal article J Biol Chem · June 6, 2003 Featured Publication Rhodobacter capsulatus xanthine dehydrogenase (XDH) forms an (alphabeta)2 heterotetramer and is highly homologous to homodimeric eukaryotic XDHs. The crystal structures of bovine XDH and R. capsulatus XDH showed that the two proteins have highly similar fo ... Full text Link to item Cite

Mechanistic and mutational studies of Escherichia coli molybdopterin synthase clarify the final step of molybdopterin biosynthesis.

Journal article J Biol Chem · April 18, 2003 Featured Publication Biosynthesis of the molybdenum cofactor, a chelate of molybdenum or tungsten with a novel pterin, occurs in virtually all organisms including humans. In the cofactor, the metal is complexed to the unique cis-dithiolene moiety located on the pyran ring of m ... Full text Link to item Cite

Structural studies of molybdopterin synthase provide insights into its catalytic mechanism.

Journal article J Biol Chem · April 18, 2003 Featured Publication Molybdenum cofactor biosynthesis is an evolutionarily conserved pathway present in eubacteria, archaea, and eukaryotes, including humans. Genetic deficiencies of enzymes involved in cofactor biosynthesis in humans lead to a severe and usually fatal disease ... Full text Link to item Cite

Role of conserved tyrosine 343 in intramolecular electron transfer in human sulfite oxidase.

Journal article J Biol Chem · January 31, 2003 Featured Publication Tyrosine 343 in human sulfite oxidase (SO) is conserved in all SOs sequenced to date. Intramolecular electron transfer (IET) rates between reduced heme (Fe(II)) and oxidized molybdenum (Mo(VI)) in the recombinant wild-type and Y343F human SO were measured ... Full text Link to item Cite

Pulsed EPR studies of the exchangeable proton at the molybdenum center of dimethyl sulfoxide reductase.

Journal article J Biol Inorg Chem · January 2003 Featured Publication Electron spin echo envelope modulation (ESEEM) spectroscopy has been used to determine the hyperfine ( hfi) and quadrupole ( nqi) interactions of the exchangeable deuteron (proton) at the Mo(V) site of DMSO reductase. The data obtained have been translated ... Full text Link to item Cite

Escherichia coli MoeA and MogA. Function in metal incorporation step of molybdenum cofactor biosynthesis.

Journal article J Biol Chem · July 12, 2002 Featured Publication Escherichia coli MoeA and MogA are required for molybdenum cofactor biosynthesis and are believed to function in the addition of molybdenum to the dithiolene of molybdopterin to form molybdenum cofactor. Here we show that moeA(-) and mogA(-) cells are able ... Full text Link to item Cite

Isolated sulfite oxidase deficiency: identification of 12 novel SUOX mutations in 10 patients.

Journal article Hum Mutat · July 2002 Featured Publication We report twelve novel mutations in patients with isolated sulfite oxidase deficiency. The mutations are in SUOX, the gene that encodes the molybdohemoprotein sulfite oxidase. These include two frameshift mutations, a four-basepair deletion (562del4) and a ... Full text Link to item Cite

Pulsed EPR studies of nonexchangeable protons near the Mo(V) center of sulfite oxidase: direct detection of the alpha-proton of the coordinated cysteinyl residue and structural implications for the active site.

Journal article J Am Chem Soc · May 29, 2002 Pulsed electron nuclear double resonance (ENDOR) spectra of nonexchangeable protons in the vicinity of the Mo(V) center of the high pH (hpH) and low pH (lpH) forms of native chicken liver sulfite oxidase (SO) and recombinant human SO have been obtained and ... Full text Link to item Cite

Isolated sulfite oxidase deficiency: mutation analysis and DNA-based prenatal diagnosis.

Journal article Prenat Diagn · May 2002 Featured Publication Isolated sulfite oxidase deficiency is an autosomal recessive, neurological disorder resulting from a defect in SUOX, the gene encoding the enzyme that catalyzes the terminal reaction in the sulfur amino acid degradation pathway. In its classical, severe f ... Full text Link to item Cite

Crystal structures of the active and alloxanthine-inhibited forms of xanthine dehydrogenase from Rhodobacter capsulatus.

Journal article Structure · January 2002 Featured Publication Xanthine dehydrogenase (XDH), a complex molybdo/iron-sulfur/flavoprotein, catalyzes the oxidation of hypoxanthine to xanthine followed by oxidation of xanthine to uric acid with concomitant reduction of NAD+. The 2.7 A resolution structure of Rhodobacter c ... Full text Link to item Cite

Molybdopterin synthase mutations in a mild case of molybdenum cofactor deficiency.

Journal article Am J Med Genet · November 22, 2001 Featured Publication Molybdenum cofactor deficiency is a rare inborn error of metabolism with generally severe symptoms, most often including neonatal seizures and severe developmental delay. We describe a patient with an unusually mild form of the disease. Two mutations in MO ... Full text Link to item Cite

Mechanism of ubiquitin activation revealed by the structure of a bacterial MoeB-MoaD complex.

Journal article Nature · November 15, 2001 Featured Publication The activation of ubiquitin and related protein modifiers is catalysed by members of the E1 enzyme family that use ATP for the covalent self-attachment of the modifiers to a conserved cysteine. The Escherichia coli proteins MoeB and MoaD are involved in mo ... Full text Link to item Cite

Characterization of Escherichia coli MoeB and its involvement in the activation of molybdopterin synthase for the biosynthesis of the molybdenum cofactor.

Journal article J Biol Chem · September 14, 2001 Featured Publication Amino acid sequence comparisons of Escherichia coli MoeB suggested that the MoeB-dependent formation of a C-terminal thiocarboxylate on the MoaD subunit of molybdopterin synthase might resemble the ubiquitin-activating step in the ubiquitin-targeted degrad ... Full text Link to item Cite

A sulfurtransferase is required in the transfer of cysteine sulfur in the in vitro synthesis of molybdopterin from precursor Z in Escherichia coli.

Journal article J Biol Chem · June 22, 2001 Featured Publication It has been shown that conversion of precursor Z to molybdopterin (MPT) by Escherichia coli MPT synthase entails the transfer of the sulfur atom of the C-terminal thiocarboxylate from the small subunit of the synthase to generate the dithiolene group of MP ... Full text Link to item Cite

An active site tyrosine influences the ability of the dimethyl sulfoxide reductase family of molybdopterin enzymes to reduce S-oxides.

Journal article J Biol Chem · April 20, 2001 Featured Publication Dimethyl sulfoxide reductase (DMSOR), trimethylamine-N-oxide reductase (TMAOR), and biotin sulfoxide reductase (BSOR) are members of a class of bacterial oxotransferases that contain the bis(molybdopterin guanine dinucleotide)molybdenum cofactor. The prese ... Full text Link to item Cite

The crystal structure of Escherichia coli MoeA and its relationship to the multifunctional protein gephyrin.

Journal article Structure · April 4, 2001 BACKGROUND: Molybdenum cofactor (Moco) biosynthesis is an evolutionarily conserved pathway present in archaea, eubacteria, and eukaryotes. In humans, genetic abnormalities in the biosynthetic pathway result in Moco deficiency, which is accompanied by sever ... Full text Link to item Cite

In vitro incorporation of nascent molybdenum cofactor into human sulfite oxidase.

Journal article J Biol Chem · January 19, 2001 Featured Publication We were able to reconstitute molybdopterin (MPT)-free sulfite oxidase in vitro with the molybdenum cofactor (Moco) synthesized de novo from precursor Z and molybdate. MPT-free human sulfite oxidase apoprotein was obtained by heterologous expression in an E ... Full text Link to item Cite

Crystal structure of molybdopterin synthase and its evolutionary relationship to ubiquitin activation.

Journal article Nat Struct Biol · January 2001 Featured Publication Molybdenum cofactor (Moco) biosynthesis is an evolutionarily conserved pathway present in eubacteria, archaea and eukaryotes, including humans. Genetic deficiencies of enzymes involved in Moco biosynthesis in humans lead to a severe and usually fatal disea ... Full text Link to item Cite

Molybdopterin from molybdenum and tungsten enzymes.

Journal article Adv Protein Chem · 2001 Featured Publication Full text Link to item Cite

The crystal structure of the Escherichia coli MobA protein provides insight into molybdopterin guanine dinucleotide biosynthesis.

Journal article J Biol Chem · December 22, 2000 The molybdenum cofactor (Moco) is found in a variety of enzymes present in all phyla and comprises a family of related molecules containing molybdopterin (MPT), a tricyclic pyranopterin with a cis-dithiolene group, as the invariant essential moiety. MPT bi ... Full text Link to item Cite

Mechanism of assembly of the Bis(Molybdopterin guanine dinucleotide)molybdenum cofactor in Rhodobacter sphaeroides dimethyl sulfoxide reductase.

Journal article J Biol Chem · December 22, 2000 A fully defined in vitro system has been developed for studying the mechanism of assembly of the bis(molybdopterin guanine dinucleotide)molybdenum cofactor in Rhodobacter sphaeroides dimethyl sulfoxide reductase (DMSOR). R. sphaeroides DMSOR expressed in a ... Full text Link to item Cite

Optimization of expression of human sulfite oxidase and its molybdenum domain.

Journal article Arch Biochem Biophys · November 15, 2000 The conditions for the heterologous expression of both untagged and His-tagged human sulfite oxidase in Escherichia coli have been optimized. Maximum production of active enzyme requires expression in a mob- cell strain at low levels of the inducer. Using ... Full text Link to item Cite

Structure of the molybdenum site of Rhodobacter sphaeroides biotin sulfoxide reductase.

Journal article Biochemistry · April 11, 2000 Conditions for heterologous expression of Rhodobacter sphaeroides biotin sulfoxide reductase in Escherichia coli were modified, resulting in a significant improvement in the yield of recombinant enzyme and enabling structural studies of the molybdenum cent ... Full text Link to item Cite

Resonance Raman characterization of biotin sulfoxide reductase. Comparing oxomolybdenum enzymes in the ME(2)SO reductase family.

Journal article J Biol Chem · March 10, 2000 Resonance Raman spectroscopy has been used to define active site structures for oxidized Mo(VI) and reduced Mo(IV) forms of recombinant Rhodobacter sphaeroides biotin sulfoxide reductase expressed in Escherichia coli. On the basis of (18)O/(16)O labeling s ... Full text Link to item Cite

Crystal structure of the gephyrin-related molybdenum cofactor biosynthesis protein MogA from Escherichia coli.

Journal article J Biol Chem · January 21, 2000 Molybdenum cofactor (Moco) biosynthesis is an evolutionarily conserved pathway in archaea, eubacteria, and eukaryotes, including humans. Genetic deficiencies of enzymes involved in this biosynthetic pathway trigger an autosomal recessive disease with sever ... Full text Link to item Cite

Isolated sulfite oxidase deficiency: review of two cases in one family.

Journal article Ophthalmology · October 1999 OBJECTIVE: The authors describe two cases of isolated sulfite oxidase deficiency found in one family. This is a rare autosomal-recessive disorder presenting at birth with seizures, severe neurologic disease, and ectopia lentis. It can be easily missed with ... Full text Link to item Cite

Re-design of Rhodobacter sphaeroides dimethyl sulfoxide reductase. Enhancement of adenosine N1-oxide reductase activity.

Journal article J Biol Chem · March 26, 1999 The periplasmic DMSO reductase from Rhodobacter sphaeroides f. sp. denitrificans has been expressed in Escherichia coli BL21(DE3) cells in its mature form and with the R. sphaeroides or E. coli N-terminal signal sequence. Whereas the R. sphaeroides signal ... Full text Link to item Cite

Human sulfite oxidase R160Q: identification of the mutation in a sulfite oxidase-deficient patient and expression and characterization of the mutant enzyme.

Journal article Proc Natl Acad Sci U S A · May 26, 1998 Sulfite oxidase catalyzes the terminal reaction in the degradation of sulfur amino acids. Genetic deficiency of sulfite oxidase results in neurological abnormalities and often leads to death at an early age. The mutation in the sulfite oxidase gene respons ... Full text Link to item Cite

Molecular basis of sulfite oxidase deficiency from the structure of sulfite oxidase.

Journal article Cell · December 26, 1997 The molybdenum-containing enzyme sulfite oxidase catalyzes the conversion of sulfite to sulfate, the terminal step in the oxidative degradation of cysteine and methionine. Deficiency of this enzyme in humans usually leads to major neurological abnormalitie ... Full text Link to item Cite

Isolated sulfite oxidase deficiency.

Journal article Neuropediatrics · December 1996 Isolated sulfite oxidase (SO) deficiency is an autosomal recessively inherited inborn error of sulfur metabolism. In this report of a ninth patient the clinical history, laboratory results, neuropathological findings and a mutation in the sulfite oxidase g ... Full text Link to item Cite

Molybdenum cofactor biosynthesis in Escherichia coli mod and mog mutants.

Journal article J Bacteriol · July 1996 The molybdopterin content of Escherichia coli mod and mog mutants was estimated by conversion to the form A derivative. The results are in accord with complete phenotypic repair of mod, and incomplete repair of mog, by culture in high concentrations of mol ... Full text Link to item Cite

Crystal structure of DMSO reductase: redox-linked changes in molybdopterin coordination.

Journal article Science · June 14, 1996 The molybdoenzyme dimethylsulfoxide (DMSO) reductase contributes to the release of dimethylsulfide, a compound that has been implicated in cloud nucleation and global climate regulation. The crystal structure of DMSO reductase from Rhodobacter sphaeroides ... Full text Link to item Cite

Molecular cloning of dimethyl sulfoxide reductase from Rhodobacter sphaeroides.

Journal article Biochim Biophys Acta · May 23, 1996 The dsrA gene encoding the molybdoenzyme dimethyl sulfoxide reductase was isolated by screening phagemid libraries containing restriction fragments of Rhodobacter sphaeroides f. sp. denitrificans genomic DNA with a pool of degenerate oligonucleotides. The ... Full text Link to item Cite

Site-directed mutagenesis of recombinant sulfite oxidase: identification of cysteine 207 as a ligand of molybdenum.

Journal article J Biol Chem · March 29, 1996 Each of the four cysteines in rat sulfite oxidase was altered by site-directed mutagenesis to serine, and the mutant proteins were expressed in Escherichia coli. Three of the replacements proved to be silent mutations, while a single cysteine, Cys-207, was ... Link to item Cite

Identification of the molybdenum cofactor of dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans as bis(molybdopterin guanine dinucleotide)molybdenum.

Journal article Arch Biochem Biophys · January 1, 1996 Chemical analysis of dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans has shown that its molybdenum center contains two molybdopterin guanine dinucleotide molecules and a single atom of molybdenum. The enzyme, which exists as ... Full text Link to item Cite

Molecular cloning of human liver sulfite oxidase.

Journal article Biochim Biophys Acta · June 9, 1995 A 2.4 kilobase cDNA clone of human sulfite oxidase was isolated from a human liver cDNA library in lambda gt10. Comparison of three sulfite oxidase sequences to several plant and fungal nitrate reductase sequences reveals a single conserved cysteine with h ... Full text Link to item Cite

Association of molybdopterin guanine dinucleotide with Escherichia coli dimethyl sulfoxide reductase: effect of tungstate and a mob mutation.

Journal article J Bacteriol · April 1995 We have identified the organic component of the molybdenum cofactor in Escherichia coli dimethyl sulfoxide reductase (DmsABC) to be molybdopterin (MPT) guanine dinucleotide (MGD) and have studied the effects of tungstate and a mob mutation on cofactor (Mo- ... Full text Link to item Cite

Resonance Raman spectroscopic characterization of the molybdopterin active site of DMSO reductase.

Journal article Biochemistry · March 7, 1995 Resonance Raman spectra are compared for Rhodobacter sphaeroides dimethyl sulfoxide reductase, an enzyme containing a molybdopterin cofactor, and two model compounds, I and II, which have pterin and quinoxaline, respectively, attached to a Cp2Mo[IV]-dithio ... Full text Link to item Cite

Investigation of the early steps of molybdopterin biosynthesis in Escherichia coli through the use of in vivo labeling studies.

Journal article J Biol Chem · January 20, 1995 The early steps in the biosynthesis of the molybdopterin portion of the molybdenum cofactor have been investigated through the use of radiolabeled precursors. Labeled guanosine was added to growing cultures of the molybdopterin-deficient Escherichia coli m ... Full text Link to item Cite

Defective molybdopterin biosynthesis: clinical heterogeneity associated with molybdenum cofactor deficiency.

Journal article J Inherit Metab Dis · 1995 A patient with molybdenum cofactor deficiency (producing the biochemical abnormalities associated with deficiencies of sulphite oxidase and xanthine dehydrogenase) clinically expressed Marfan-like habitus with dislocated lenses, vertebral abnormality, lear ... Full text Link to item Cite

An HPLC assay for detection of elevated urinary S-sulphocysteine, a metabolic marker of sulphite oxidase deficiency.

Journal article J Inherit Metab Dis · 1995 Sulphite oxidase deficiency occurs in man in two forms, as the isolated deficiency and as a syndrome of combined molybdoenzyme deficiency. This latter pleiotropic condition has as its underlying cause a defect in the synthesis of the molybdenum cofactor re ... Full text Link to item Cite

Specific incorporation of molybdopterin in xanthine dehydrogenase of Pseudomonas aeruginosa.

Journal article Arch Biochem Biophys · February 1, 1994 All known molybdoenzymes other than nitrogenase contain the metal in association with molybdopterin or one of its dinucleotide variants. All eukaryotic molybdoproteins have been found to contain only molybdopterin, whereas the majority of bacterial enzymes ... Full text Link to item Cite

Molecular cloning of rat liver sulfite oxidase. Expression of a eukaryotic Mo-pterin-containing enzyme in Escherichia coli.

Journal article J Biol Chem · January 7, 1994 The cDNA encoding sulfite oxidase has been cloned from a rat liver cDNA library. The gene contains a single open reading frame of 1464 nucleotides encoding a protein of 488 amino acids. The deduced amino acid sequence contains a 22-residue amino-terminal p ... Link to item Cite

Structural characterization of a molybdopterin precursor.

Journal article J Biol Chem · June 25, 1993 Purification and structural characterization of a novel pterin that is the immediate biosynthetic precursor for molybdopterin formation in Escherichia coli has been accomplished. The precursor is purified from acid extracts of cells of the Escherichia coli ... Link to item Cite

The biosynthesis of molybdopterin in Escherichia coli. Purification and characterization of the converting factor.

Journal article J Biol Chem · June 25, 1993 Molybdopterin, the universal component of the pterin molybdenum cofactors, contains a dithiolene group serving to bind Mo. Addition of the dithiolene sulfurs to a molybdopterin precursor requires the activity of the converting factor. Active converting fac ... Link to item Cite

In vitro synthesis of molybdopterin from precursor Z using purified converting factor. Role of protein-bound sulfur in formation of the dithiolene.

Journal article J Biol Chem · June 25, 1993 The pterin component of the molybdenum cofactor, termed molybdopterin, is synthesized in Escherichia coli by enzymes encoded at the chl loci. A late step in the biosynthetic pathway, the conversion of a molybdopterin intermediate, precursor Z, to molybdopt ... Link to item Cite

Identification of molybdopterin as the organic component of the tungsten cofactor in four enzymes from hyperthermophilic Archaea.

Journal article J Biol Chem · March 5, 1993 The hyperthermophilic Archaea represent some of the most ancient organisms on earth. A study of enzymatic cofactors in these organisms could provide basic information on the origins of related cofactors in man and other more recently evolved organisms. To ... Link to item Cite

Human molybdenum cofactor deficiency.

Journal article Adv Exp Med Biol · 1993 Full text Link to item Cite

The pterin molybdenum cofactors.

Journal article J Biol Chem · May 25, 1992 Link to item Cite

31P-NMR of free and protein-bound molybdopterin guanine dinucleotide.

Journal article Biofactors · January 1992 Molybdopterin guanine dinucleotide was studied by 31P-NMR in the free, iodoacetamide derivatized form [di(carboxamidomethyl)molybdopterin] and in the native state in the dimethyl sulfoxide reductase from Rhodobacter sphaeroides. The spectra confirm the pre ... Link to item Cite

Rat sulfite oxidase antibodies cross-react with two gene family-related proteins: albumin and vitamin D-binding protein.

Journal article Arch Biochem Biophys · November 15, 1991 Screening lambda cDNA libraries from rat liver with antibody to native rat liver sulfite oxidase (RLSO) showed cross-reaction with two proteins that belong to the same gene family: serum albumin and vitamin D-binding protein. Antibodies raised against nati ... Full text Link to item Cite

The mechanisms of inactivation of sulfite oxidase by periodate and arsenite.

Journal article J Biol Chem · September 5, 1991 The inactivation of sulfite oxidase, a molybdoenzyme containing the Mo cofactor, by arsenite and periodate was investigated. In contrast to ferricyanide (Gardlik, S., and Rajagopalan, K.V. (1991) J. Biol. Chem. 266, 4889-4895), neither of these reagents ca ... Link to item Cite

Molybdenum cofactor biosynthesis in Escherichia coli. Requirement of the chlB gene product for the formation of molybdopterin guanine dinucleotide.

Journal article J Biol Chem · July 5, 1991 The chlorate-resistant mutants of Escherichia coli are affected in the biosynthesis of the molybdenum cofactor and show pleiotropic loss of the activities of those enzymes which require the cofactor. The molybdenum cofactor in all molybdoenzymes other than ... Link to item Cite

Identification of a molybdopterin-containing molybdenum cofactor in xanthine dehydrogenase from Pseudomonas aeruginosa.

Journal article Biofactors · June 1991 Xanthine dehydrogenase has been purified from Pseudomonas aeruginosa cultured on a rich medium and induced with hypoxanthine. The enzyme was shown to contain FAD, iron sulfur centers and a molybdenum cofactor as prosthetic groups. Analysis of the molybdenu ... Link to item Cite

Oxidation of molybdopterin in sulfite oxidase by ferricyanide. Effect on electron transfer activities.

Journal article J Biol Chem · March 15, 1991 The attenuation of the sulfite:cytochrome c activity of sulfite oxidase upon treatment with ferricyanide was demonstrated to be the result of oxidation of the pterin ring of the molybdenum cofactor in the enzyme. Oxidation of molybdopterin (MPT) was detect ... Link to item Cite

Identification of molybdopterin guanine dinucleotide in formate dehydrogenase from Methanobacterium formicicum.

Journal article FEMS Microbiol Lett · January 15, 1991 The pterin cofactor in formate dehydrogenase isolated from Methanobacterium formicium is identified as molybdopterin guanine dinucleotide. The pterin, stabilized as the alkylated, dicarboxamidomethyl derivative, is shown to have absorption and chromatograp ... Full text Link to item Cite

Spectroscopic studies of the molybdenum-containing dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans.

Journal article J Biol Chem · January 5, 1991 Absorption and EPR spectroscopic properties of purified dimethyl sulfoxide (Me2SO) reductase from Rhodobacter sphaeroides f. sp. denitrificans have been examined. The absence of prosthetic groups other than the molybdenum center in the enzyme has made it p ... Link to item Cite

Novel aspects of the biochemistry of the molybdenum cofactor.

Journal article Adv Enzymol Relat Areas Mol Biol · 1991 Full text Link to item Cite

Prenatal diagnosis of molybdenum cofactor deficiency by assay of sulphite oxidase activity in chorionic villus samples.

Journal article J Inherit Metab Dis · 1991 Molybdenum cofactor deficiency is characterized by the absence of sulphite oxidase, xanthine dehydrogenase and aldehyde oxidase, the three known enzymes in man that require the cofactor for their activity. Prenatal diagnosis of the deficiency may be perfor ... Full text Link to item Cite

Isolation and characterization of a second molybdopterin dinucleotide: molybdopterin cytosine dinucleotide.

Journal article Arch Biochem Biophys · December 1990 The pterin cofactor (bactopterin) in the molybdoenzyme CO dehydrogenase isolated from Pseudomonas carboxydoflava has previously been shown to differ from molybdopterin in molecular mass, phosphate content, stability, and other properties, implying a novel ... Full text Link to item Cite

The folate cofactor of Escherichia coli DNA photolyase acts catalytically.

Journal article J Biol Chem · October 25, 1990 Escherichia coli DNA photolyase catalyzes the light-driven (300-500 nm) repair of pyrimidine dimers formed between adjacent pyrimidine bases in DNA exposed to UV light (200-300 nm). The light-driven repair process is facilitated by two enzyme-bound cofacto ... Link to item Cite

The state of reduction of molybdopterin in xanthine oxidase and sulfite oxidase.

Journal article J Biol Chem · August 5, 1990 Methods have been devised to examine the spectral properties and state of reduction of the pterin ring of molybdopterin (MPT) in milk xanthine oxidase and the Mo-containing domain of rat liver sulfite oxidase. The absorption spectrum of the native pterin w ... Link to item Cite

The presence and distribution of reduced folates in Escherichia coli dihydrofolate reductase mutants.

Journal article J Biol Chem · June 15, 1990 Escherichia coli DNA photolyase was overproduced and purified from each of two mutant E. coli strains lacking dihydrofolate reductase. The extent of over-production in the mutants was comparable to that seen in the wild type strain. Examination of the isol ... Link to item Cite

Molybdopterin guanine dinucleotide: a modified form of molybdopterin identified in the molybdenum cofactor of dimethyl sulfoxide reductase from Rhodobacter sphaeroides forma specialis denitrificans.

Journal article Proc Natl Acad Sci U S A · April 1990 The nature of molybdenum cofactor in the bacterial enzyme dimethyl sulfoxide reductase has been investigated by application of alkylation conditions that convert the molybdenum cofactor in chicken liver sulfite oxidase and milk xanthine oxidase to the stab ... Full text Link to item Cite

Covalently bound phosphate residues in bovine milk xanthine oxidase and in glucose oxidase from Aspergillus niger: a reevaluation.

Journal article Proc Natl Acad Sci U S A · September 1989 The reported presence of covalently bound phosphate residues in flavoproteins has significant implications with regard to the catalytic mechanisms and structural stability of the specific enzymes themselves and in terms of general cellular metabolic regula ... Full text Link to item Cite

The structure of a molybdopterin precursor. Characterization of a stable, oxidized derivative.

Journal article J Biol Chem · August 15, 1989 An oxidized pterin species, termed compound Z, has been isolated from molybdenum cofactor-deficient mutants of Escherichia coli and shown to be the direct product of oxidation of a molybdopterin precursor which accumulates in these mutants. The complete st ... Link to item Cite

Role of enzyme-bound 5,10-methenyltetrahydropteroylpolyglutamate in catalysis by Escherichia coli DNA photolyase.

Journal article J Biol Chem · June 5, 1989 DNA photolyase catalyzes the photoreversal of pyrimidine dimers. The enzymes from Escherichia coli and yeast contain a flavin chromophore and a folate cofactor, 5,10-methenyltetrahydropteroylpolyglutamate. E. coli DNA photolyase contains about 0.3 mol of f ... Link to item Cite

Two proteins encoded at the chlA locus constitute the converting factor of Escherichia coli chlA1.

Journal article J Bacteriol · June 1989 Molybdopterin (MPT) is not produced by the Escherichia coli mutants chlA1, chlM, or chlN or by the Neurospora crassa mutant nit-1. Extracts of E. coli chlA1 contain an activity, the converting factor, which is functionally defined by its ability to convert ... Full text Link to item Cite

Molybdopterin--problems and perspectives.

Journal article Biofactors · December 1988 Structural studies on several derivatives of molybdopterin, the organic component of the molybdenum cofactor common to virtually all molybdoenzymes, have provided definitive evidence for the presence of a reduced pterin ring with a 6-alkyl side-chain conta ... Link to item Cite

Identification of the second chromophore of Escherichia coli and yeast DNA photolyases as 5,10-methenyltetrahydrofolate.

Journal article Proc Natl Acad Sci U S A · April 1988 Denaturation of DNA photolyase (deoxyribodipyrimidine photolyase, EC 4.1.99.3) from Escherichia coli with guanidine hydrochloride or acidification to pH 2 released, in addition to FAD, a chromophore with the spectral and chromatographic properties of a red ... Full text Link to item Cite

The structure of the molybdenum cofactor. Characterization of di-(carboxamidomethyl)molybdopterin from sulfite oxidase and xanthine oxidase.

Journal article J Biol Chem · December 5, 1987 A di-(carboxamidomethyl) derivative of molybdopterin, the organic component of the molybdenum cofactor, has been prepared under conditions favoring retention of all of the structural features of the molecule. The specific radioactivity of [1-14C]iodoacetam ... Link to item Cite

A molybdopterin-free form of xanthine oxidase.

Journal article Arch Biochem Biophys · December 1987 A previously unidentified fraction lacking xanthine:O2 activity has been isolated during affinity chromatography of bovine milk xanthine oxidase preparations on Sepharose 4B/folate gel. Unlike active, desulfo, or demolybdo forms of xanthine oxidase, this f ... Full text Link to item Cite

Molybdenum--an essential trace element.

Journal article Nutr Rev · November 1987 Full text Link to item Cite

In vitro system for molybdopterin biosynthesis.

Journal article J Bacteriol · January 1987 A high-Mr fraction present in chl+ and chlA1 strains of Escherichia coli synthesizes molybdopterin (MPT) from the low-Mr fraction of several MPT-deficient mutants. Using this in vitro complementation as an assay, we have partially characterized the high-Mr ... Full text Link to item Cite

Involvement of chlA, E, M, and N loci in Escherichia coli molybdopterin biosynthesis.

Journal article J Bacteriol · January 1987 All molybdenum enzymes except nitrogenase contain a common molybdenum cofactor, whose organic moiety is a novel pterin called molybdopterin (MPT). To assist in elucidating the biosynthetic pathway of MPT, two MPT-deficient mutants of Escherichia coli K-12 ... Full text Link to item Cite

Chemistry and biology of the molybdenum cofactor.

Journal article Biochem Soc Trans · April 1985 Full text Link to item Cite

In vitro reconstitution of nitrate reductase activity of the Neurospora crassa mutant nit-1: specific incorporation of molybdopterin.

Journal article Arch Biochem Biophys · September 1984 The reduced, metal-free pterin of the molybdenum cofactor has been termed molybdopterin. Oxidation of any molybdopterin-containing protein in the presence or absence of iodine yields oxidized molybdopterin derivatives termed Form A and Form B, respectively ... Full text Link to item Cite

The pterin component of the molybdenum cofactor. Structural characterization of two fluorescent derivatives.

Journal article J Biol Chem · May 10, 1984 Two stable fluorescent derivatives of molybdopterin have been structurally characterized. Form A is an oxidized pterin with a 6-alkyl substituent. Results of chemical, mass spectral, and NMR studies are consistent with the side chain formulation -C identic ... Link to item Cite

Selenite binding to carbon monoxide oxidase from Pseudomonas carboxydovorans. Selenium binds covalently to the protein and activates specifically the CO----methylene blue reaction.

Journal article J Biol Chem · May 10, 1984 The CO----methylene blue and CO----dichlorophenol indophenol activities of carbon monoxide oxidase were specifically activated upon aerobic incubation with selenite, whereas the NADH----methylene blue activity was not altered. Fully active enzyme contained ... Link to item Cite

The relationship of Mo, molybdopterin, and the cyanolyzable sulfur in the Mo cofactor.

Journal article Arch Biochem Biophys · April 1984 Reconstitution of the apoprotein of the molybdoenzyme nitrate reductase in extracts of the Neurospora crassa mutant nit-1 with molybdenum cofactor released by denaturation of purified molybdoenzymes is efficient in the absence of exogenous MoO2-4 under def ... Full text Link to item Cite

Molybdopterin in carbon monoxide oxidase from carboxydotrophic bacteria.

Journal article J Bacteriol · February 1984 The carbon monoxide oxidases (COXs) purified from the carboxydotrophic bacteria Pseudomonas carboxydohydrogena and Pseudomonas carboxydoflava were found to be molybdenum hydroxylases, identical in cofactor composition and spectral properties to the recentl ... Full text Link to item Cite

Electron paramagnetic resonance studies on the molybdenum center of assimilatory NADH:nitrate reductase from Chlorella vulgaris.

Journal article J Biol Chem · January 25, 1984 The assimilatory nitrate reductase from Chlorella contains flavin, heme, and molybdenum as prosthetic groups. The molybdenum in assimilatory nitrate reductase is associated with a pterin moiety (molybdopterin) as evidenced by the ability of the enzyme to d ... Link to item Cite

Absence of hepatic molybdenum cofactor: an inborn error of metabolism leading to a combined deficiency of sulphite oxidase and xanthine dehydrogenase.

Journal article J Inherit Metab Dis · 1983 Five patients with a combined deficiency of xanthine dehydrogenase, sulphite oxidase and, possibly, also of aldehyde oxidase are described. This remarkable coincidence of three inborn errors of metabolism in a single individual was demonstrated to result f ... Full text Link to item Cite

Structural and metabolic relationship between the molybdenum cofactor and urothione.

Journal article Proc Natl Acad Sci U S A · November 1982 The molybdenum cofactor isolated from sulfite oxidase (sulfite: ferricytochrome c oxidoreductase, EC 1.8.2.1) and xanthine dehydrogenase (xanthine:NAD+ oxidoreductase, EC 1.2.1.37) in the presence of iodine and KI (form A) has been shown to contain a pteri ... Full text Link to item Cite

Properties of the prosthetic groups of rabbit liver aldehyde oxidase: a comparison of molybdenum hydroxylase enzymes.

Journal article Biochemistry · July 20, 1982 Rabbit liver aldehyde oxidase (AO), like milk xanthine oxidase (XO) and chicken liver xanthine dehydrogenase (XDH), possesses the following prosthetic groups: FAD, a functional Mo center, and two spectroscopically distinct iron-sulfur centers, one with gav ... Full text Link to item Cite

The pterin of the molybdenum cofactor.

Journal article Fed Proc · July 1982 The molybdenum cofactor common to a variety of molybdoenzymes has been shown to contain a novel pterin. The pterin has been isolated from sulfite oxidase from several sources, xanthine-oxidizing enzymes from milk and chicken liver, and nitrate reductase of ... Link to item Cite

Drosophila melanogaster ma-l mutants are defective in the sulfuration of desulfo Mo hydroxylases.

Journal article J Biol Chem · April 10, 1982 Xanthine dehydrogenase was purified more than 1500-fold from crude extracts of wild type Drosophila melanogaster. Like the bovine milk and chicken liver enzymes, the purified Drosophila enzyme was inactivated by cyanide, and the cyanide-inactivated desulfo ... Link to item Cite

Rat liver L-glutamate dehydrogenase, malate dehydrogenase, D-beta-hydroxybutyrate dehydrogenase, and sulfite oxidase are each synthesized as larger precursors by cytoplasmic free polysomes.

Journal article J Biol Chem · April 10, 1982 Four cytoplasmically synthesized rat liver mitochondrial enzymes, located either as soluble enzymes in the mitochondrial matrix (L-glutamate dehydrogenase and malate dehydrogenase or in the intermembrane space (sulfite oxidase) or as an integral membrane p ... Link to item Cite

Evidence for the inorganic nature of the cyanolyzable sulfur of molybdenum hydroxylases.

Journal article J Biol Chem · February 10, 1982 Activation of the desulfo forms of milk xanthine oxidase, chicken liver xanthine dehydrogenase, and aldehyde oxidase with S2- is greatly facilitated in the presence of reducing agents. Upon anaerobic incubation with 1 mM S2- and 1 mM dithionite, desulfo xa ... Link to item Cite

Molybdenum metabolism.

Journal article Am J Dis Child · November 1980 Full text Link to item Cite

Inborn errors of molybdenum metabolism: combined deficiencies of sulfite oxidase and xanthine dehydrogenase in a patient lacking the molybdenum cofactor.

Journal article Proc Natl Acad Sci U S A · June 1980 A patient suffering from a combined deficiency of sulfite oxidase (sulfite dehydrogenase; sulfite:ferricytochrome c oxidoreductase, EC 1.8.2.1) and xanthine dehydrogenase (xanthine:NAD+ oxidoreductase, EC 1.2.1.37) is described. The patient displays severe ... Full text Link to item Cite

Mechanisms of inactivation of molybdoenzymes by cyanide.

Journal article J Biol Chem · April 10, 1980 The reduced forms of xanthine oxidase, xanthine dehydrogenase, aldehyde oxidase, and sulfite oxidase are inactivated by cyanide. Following gel filtration to remove excess of reductant and cyanide, the isolated enzymes remain inactive. Thiocyanate, a produc ... Link to item Cite

Characterization of the molybdenum cofactor of sulfite oxidase, xanthine, oxidase, and nitrate reductase. Identification of a pteridine as a structural component.

Journal article J Biol Chem · March 10, 1980 The molybdenum cofactor has been isolated in an oxidized inactive form from purified molybdoenzymes. The isolated material is shown to be a novel pterin. The active cofactor is presumably composed of molybdenum and a reduced form of the pterin. ... Link to item Cite

The kinetic mechanism of xanthine dehydrogenase and related enzymes.

Journal article Eur J Biochem · March 1980 Xanthine dehydrogenase and related enzymes contain multicomponent internal electron transfer chains. The topographical arrangement of this chain in such that the oxidation of substrate and the reduction of the electron acceptor occur at separate non-overla ... Full text Link to item Cite

Isolation of the domain containing the molybdenum, iron-sulfur I, and iron-sulfur II centers of chicken liver xanthine dehydrogenase.

Journal article J Biol Chem · November 10, 1979 Chicken liver xanthine dehydrogenase, like other xanthine-oxidizing enzymes, is a dimer of Mr = 150,000 subunits. Each subunit contains one molybdenum, one FAD, and two distinct Fe2S2 centers. Treatment with a number of proteases shows that the native enzy ... Link to item Cite

Characterization of molybdenum cofactor from Escherichia coli.

Journal article J Bacteriol · October 1979 Molybdenum cofactor activity was found in the soluble fraction of cell-free extracts of Escherichia coli grown aerobically in media supplemented with molybdate. Cofactor was detected by its ability to complement the nitrate reductase-deficient mutant of Ne ... Full text Link to item Cite

Syncatalytic modification of chicken liver xanthine dehydrogenase by hydrogen peroxide. The nature of the reaction.

Journal article J Biol Chem · September 25, 1979 Xanthine dehydrogenase engaged in catalyzing the oxidation of substrate by oxygen is repidly inactivated by the hydrogen peroxide generated during the reaction. Experimental evidence shows that peroxide reacts more readily with the reduced than with the ox ... Link to item Cite

The oxidation of sulphite in animals systems.

Journal article Ciba Found Symp · 1979 In animals the terminal step in the pathway for degradation of sulphur-containing amino acids is the oxidation of sulphite to sulphate. This reaction is catalysed by the enzyme sulphite oxidase. The enzyme contains molybdenum and a cytochrome b5 type haem, ... Full text Link to item Cite

Studies on the zinc content of Cd-induced thionein.

Journal article Arch Biochem Biophys · June 1978 Full text Link to item Cite

The interaction of arsenite with the molybdenum center of chicken liver xanthine dehydrogenase.

Journal article Bioinorg Chem · 1978 Inactivation of chicken liver xanthine dehydrogenase by arsenite is reflected in the molybdenum electron paramagnetic resonance signal at g = 1.97. The arsenite spectrum shows additional splittings and considerable broadening yet remains comparable to the ... Full text Link to item Cite

Sulfite oxidase deficiency. Biochemical and clinical investigations of a hereditary metabolic disorder in sulfur metabolism.

Journal article N Engl J Med · November 10, 1977 Study of a 4 1/2-year-old boy with the unusual combination of acute infantile hemiplegia, ectopia lentis and the absence of homocystinuria showed large amounts of abnormal sulfur-containing metabolites (sulfite, thiosulfate and S-sulfocysteine) in the urin ... Full text Link to item Cite

In vitro reconstitution of demolybdosulfite oxidase by molybdate.

Journal article J Biol Chem · July 25, 1977 Reconstitution of purified demolybdosulfite oxidase from rat liver has been achieved using inorganic molybdate as the source of molybdenum. The activation process has a pH optimum of 7.4 and is dependent on concentrations of molybdate and demolybdoenzyme. ... Link to item Cite

Metal sites of copper-zinc superoxide dismutase.

Journal article Biochemistry · May 3, 1977 Silver-copper and silver-cobalt proteins have been prepared in which Ag+ resides in the native copper site of superoxide dismutase and either Cu2+ of Co2+ reside in the zinc site. The electron paramagnetic resonance (EPR) spectrum of the copper and the vis ... Full text Link to item Cite

Tryptic cleavage of rat liver sulfite oxidase. Isolation and characterization of molybdenum and heme domains.

Journal article J Biol Chem · March 25, 1977 Treatment of rat liver sulfite oxidase with trypsin leads to loss of ability to oxidize sulfite in the presence of cytochrome c as electron acceptor. Ability to oxidize sulfite with ferricyanide as acceptor is undiminished, while sulfite leads to O2 activi ... Link to item Cite

Sulfite oxidase deficiency.

Journal article Arch Environ Health · 1977 Link to item Cite

Electron paramagnetic resonance of the tungsten derivative of rat liver sulfite oxidase.

Journal article J Biol Chem · September 25, 1976 Sulfite oxidase purified from livers of tungsten-treated rats has been used for EPR studies of tungsten substituted at the molybdenum site of the enzyme in a fraction of the molecules. The EPR signal of W(V) in sulfite oxidase is quite similar to that of M ... Link to item Cite

Purification and properties of sulfite oxidase from human liver.

Journal article J Clin Invest · September 1976 Sulfite oxidase has been purified to near homogeneity from human liver. Properties of the molecule have been investigated and compared to those of the rat liver enzyme which has been isolated in a pure form. Both proteins exist as dimeric molecules with on ... Full text Link to item Cite

Human sulfite oxidase deficiency. Characterization of the molecular defect in a multicomponent system.

Journal article J Clin Invest · September 1976 Frozen liver tissue from an individual identified several years ago as sulfite oxidase deficient has been reexamined in light of new knowledge which has been obtained regarding the enzyme. It has been established that hepatic molybdenum levels and xanthine ... Full text Link to item Cite

Chemistry and biology of copper-chelatin.

Journal article Adv Exp Med Biol · 1976 Full text Link to item Cite

Metal-induced formation of metallothionein in rat liver.

Journal article Arch Biochem Biophys · September 1975 Full text Link to item Cite

Copper-induced synthesis of copper-chelatin in rat liver.

Journal article Arch Biochem Biophys · September 1975 Full text Link to item Cite

Copper-chelatin: isolation from various eucaryotic sources.

Journal article Arch Biochem Biophys · September 1975 Full text Link to item Cite

The role of superoxide anion generation in phagocytic bactericidal activity. Studies with normal and chronic granulomatous disease leukocytes.

Journal article J Clin Invest · June 1975 The capacity of human phagocytes to generate superoxide anion (O2-), a free radical of oxygen, and a possible role for this radical or its derivatives in the killing of phagocytized bacteria were explored using leukocytes from normal individuals and patien ... Full text Link to item Cite

Total reconstitution of copper-zinc superoxide dismutase.

Journal article J Biol Chem · November 25, 1974 Link to item Cite

Molecular basis of the biological function of molybdenum: the relationship between sulfite oxidase and the acute toxicity of bisulfite and SO2.

Journal article Proc Natl Acad Sci U S A · December 1973 The administration of tungsten to rats maintained on a low molybdenum diet resulted in a dose- and time-dependent loss of sulfite oxidase (EC 1.8.3.1) and xanthine oxidase (EC 1.2.3.2) activities and hepatic molybdenum. These tungsten-treated animals appea ... Full text Link to item Cite

Hepatic sulfite oxidase. A functional role for molybdenum.

Journal article J Biol Chem · January 25, 1971 Link to item Cite

Isolation of -L-glutaminyl 4-hydroxybenzene and -L-glutaminyl 3,4-benzoquinone: a natural sulfhydryl reagent, from sporulating gill tissue of the mushroom Agaricus bisporus.

Journal article Proc Natl Acad Sci U S A · October 1970 Early in the development of spores, there appears in gill tissue of the mushroom Agaricus bisporus a red pigment that inhibits mitochondrial respiration. The inhibitor and its immediate precursor were isolated from the mushroom and identified as gamma-L-gl ... Full text Link to item Cite

THE ABSORPTION SPECTRA OF IRON-FLAVOPROTEINS.

Journal article J Biol Chem · May 1964 Link to item Cite

Oxidation of phenazine methosulfate by hepatic aldehyde oxidase.

Journal article Biochem Biophys Res Commun · June 19, 1962 Full text Link to item Cite

Competitive inhibition of enzyme activity by urea.

Journal article J Biol Chem · April 1961 Link to item Cite