Skip to main content
Journal cover image

Colonial morphology of staphylococci on Memphis agar: phase variation of slime production, resistance to beta-lactam antibiotics, and virulence.

Publication ,  Journal Article
Christensen, GD; Baddour, LM; Madison, BM; Parisi, JT; Abraham, SN; Hasty, DL; Lowrance, JH; Josephs, JA; Simpson, WA
Published in: J Infect Dis
June 1990

The growth of Staphylococcus epidermidis sensu stricto and Staphylococcus saprophyticus on Memphis agar yielded up to 6 morphotypes with each strain. With S. epidermidis, one morphotype produced slime (rho) but became non-slime-producing (epsilon) at a high frequency. The slime-producing rho variants were methicillin-resistant and more virulent than methicillin-susceptible epsilon variants in an endocarditis model. With S. saprophyticus, phase variation was of higher frequency. Nitrosoguanidine mutagenesis produced a stable blue epsilon form that was more virulent than the parent in a mouse model of urinary tract infection. Mutants with the blue epsilon phenotype differed from gold epsilon parents in a variety of phenotypic properties, including increased resistance to oxacillin. These staphylococcal species have a high frequency of phase variation: Phase variants differ in antibiotic resistance and virulence, which is only partially correlated with suggested virulence factors such as slime production.

Duke Scholars

Published In

J Infect Dis

DOI

ISSN

0022-1899

Publication Date

June 1990

Volume

161

Issue

6

Start / End Page

1153 / 1169

Location

United States

Related Subject Headings

  • beta-Lactams
  • Virulence
  • Urinary Tract Infections
  • Staphylococcus epidermidis
  • Staphylococcus
  • Staphylococcal Infections
  • Rats, Inbred Strains
  • Rats
  • Phenotype
  • Phagocytosis
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Christensen, G. D., Baddour, L. M., Madison, B. M., Parisi, J. T., Abraham, S. N., Hasty, D. L., … Simpson, W. A. (1990). Colonial morphology of staphylococci on Memphis agar: phase variation of slime production, resistance to beta-lactam antibiotics, and virulence. J Infect Dis, 161(6), 1153–1169. https://doi.org/10.1093/infdis/161.6.1153
Christensen, G. D., L. M. Baddour, B. M. Madison, J. T. Parisi, S. N. Abraham, D. L. Hasty, J. H. Lowrance, J. A. Josephs, and W. A. Simpson. “Colonial morphology of staphylococci on Memphis agar: phase variation of slime production, resistance to beta-lactam antibiotics, and virulence.J Infect Dis 161, no. 6 (June 1990): 1153–69. https://doi.org/10.1093/infdis/161.6.1153.
Christensen GD, Baddour LM, Madison BM, Parisi JT, Abraham SN, Hasty DL, et al. Colonial morphology of staphylococci on Memphis agar: phase variation of slime production, resistance to beta-lactam antibiotics, and virulence. J Infect Dis. 1990 Jun;161(6):1153–69.
Christensen, G. D., et al. “Colonial morphology of staphylococci on Memphis agar: phase variation of slime production, resistance to beta-lactam antibiotics, and virulence.J Infect Dis, vol. 161, no. 6, June 1990, pp. 1153–69. Pubmed, doi:10.1093/infdis/161.6.1153.
Christensen GD, Baddour LM, Madison BM, Parisi JT, Abraham SN, Hasty DL, Lowrance JH, Josephs JA, Simpson WA. Colonial morphology of staphylococci on Memphis agar: phase variation of slime production, resistance to beta-lactam antibiotics, and virulence. J Infect Dis. 1990 Jun;161(6):1153–1169.
Journal cover image

Published In

J Infect Dis

DOI

ISSN

0022-1899

Publication Date

June 1990

Volume

161

Issue

6

Start / End Page

1153 / 1169

Location

United States

Related Subject Headings

  • beta-Lactams
  • Virulence
  • Urinary Tract Infections
  • Staphylococcus epidermidis
  • Staphylococcus
  • Staphylococcal Infections
  • Rats, Inbred Strains
  • Rats
  • Phenotype
  • Phagocytosis