How does protein architecture facilitate the transduction of ATP chemical-bond energy into mechanical work? The cases of nitrogenase and ATP binding-cassette proteins.

Published

Journal Article

Transduction of adenosine triphosphate (ATP) chemical-bond energy into work to drive large-scale conformational changes is common in proteins. Two specific examples of ATP-utilizing proteins are the nitrogenase iron protein and the ATP binding-cassette transporter protein, BtuCD. Nitrogenase catalyzes biological nitrogen fixation whereas BtuCD transports vitamin B(12) across membranes. Both proteins drive their reactions with ATP. To interpret how the mechanical force generated by ATP binding and hydrolysis is propagated in these proteins, a coarse-grained elastic network model is employed. The analysis shows that subunits of the proteins move against each other in a concerted manner. The lowest-frequency modes of the nitrogenase iron protein and of the ATP binding-cassette transporter BtuCD protein are found to link the functionally critical domains, and these modes are suggested to be responsible for (at least the initial stages) large-scale ATP-coupled conformational changes.

Full Text

Duke Authors

Cited Authors

  • Liao, J-L; Beratan, DN

Published Date

  • August 2004

Published In

Volume / Issue

  • 87 / 2

Start / End Page

  • 1369 - 1377

PubMed ID

  • 15298939

Pubmed Central ID

  • 15298939

Electronic International Standard Serial Number (EISSN)

  • 1542-0086

International Standard Serial Number (ISSN)

  • 0006-3495

Digital Object Identifier (DOI)

  • 10.1529/biophysj.103.038653

Language

  • eng