1SS1

STAPHYLOCOCCAL PROTEIN A, B-DOMAIN, Y15W MUTANT, NMR, 25 STRUCTURES

Summary for 1SS1

• Entry DOI: 10.2210/pdb1ss1/pdb
• Descriptor: Immunoglobulin G binding protein A (1 entity in total)
• Functional Keywords: immunoglobulin-binding protein, three-helical bundle, immune system
• Biological source: Staphylococcus aureus
• Cellular location: Secreted, cell wall; Peptidoglycan-anchor (Potential): P38507
• Total number of polymer chains: 1
• Total formula weight: 6945.58

Authors

Sato, S.,Religa, T.L.,Daggett, V.,Fersht, A.R. (deposition date: 2004-03-23, release date: 2004-04-06, Last modification date: 2024-05-22)

Primary citation

Sato, S.,Religa, T.L.,Daggett, V.,Fersht, A.R.
From The Cover: Testing protein-folding simulations by experiment: B domain of protein A.
Proc.Natl.Acad.Sci.USA, 101:6952-6956, 2004

PubMed Abstract: We have assessed the published predictions of the pathway of folding of the B domain of protein A, the pathway most studied by computer simulation. We analyzed the transition state for folding of the three-helix bundle protein, by using experimental Phi values on some 70 suitable mutants. Surprisingly, the third helix, which has the most stable alpha-helical structure as a peptide fragment, is poorly formed in the transition state, especially at its C terminus. The protein folds around a nearly fully formed central helix, which is stabilized by extensive hydrophobic side chain interactions. The turn connecting the poorly structured first helix to the central helix is unstructured, but the turn connecting the central helix to the third is in the process of being formed as the N-terminal region of the third helix begins to coalesce. The transition state is inconsistent with a classical framework mechanism and is closer to nucleation-condensation. None of the published atomistic simulations are fully consistent with the experimental picture although many capture important features. There is a continuing need for combining simulation with experiment to describe folding pathways, and of continued testing to improve predictive methods.

PubMed: 15069202
DOI: 10.1073/pnas.0401396101

Experimental method

SOLUTION NMR