1hh9
From Proteopedia
ANTI-P24 (HIV-1) FAB FRAGMENT CB41 COMPLEXED WITH A PEPTIDE
Overview
We identified evolutionary pathways for the inter- conversion of three sequentially and structurally unrelated peptides, GATPEDLNQKL, GLYEWGGARI and FDKEWNLIEQN, binding to the same site of the hypervariable region of the anti-p24 (HIV-1) monoclonal antibody CB4-1. Conversion of these peptides into each other could be achieved in nine or 10 single amino acid substitution steps without loss of antibody binding. Such pathways were identified by analyzing all 7 620 480 pathways connecting 2560 different peptides, and testing them for CB4-1 binding. The binding modes of intermediate peptides of selected optimal pathways were characterized using complete sets of substitution analogs, revealing that a number of sequential substitutions accumulated without changing the pattern of key interacting residues. At a distinct step, however, one single amino acid exchange induces a sudden change in the binding mode, indicating a flip in specificity and conformation. Our data represent a model of how different specificities, structures and functions might evolve in protein-protein recognition.
About this Structure
1HH9 is a Protein complex structure of sequences from Mus musculus. Full crystallographic information is available from OCA.
Reference
Evolutionary transition pathways for changing peptide ligand specificity and structure., Hoffmuller U, Knaute T, Hahn M, Hohne W, Schneider-Mergener J, Kramer A, EMBO J. 2000 Sep 15;19(18):4866-74. PMID:10990450 Page seeded by OCA on Fri May 2 18:50:43 2008
