Open AccessModelling of steric structure of a periplasmic molecular chaperone Caf1M of Yersinia pestis , a prototype member of a subfamily with characteristic structural and functional features
Author(s) -
Zav'yalov Vladimir P.,
Zav'yalova Galina A.,
Denesyuk Alexander I.,
Korpela Timo
Publication year - 1995
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.1995.tb00074.x
Subject(s) - periplasmic space , subfamily , yersinia pestis , biology , chaperone (clinical) , steric effects , computational biology , microbiology and biotechnology , biochemistry , stereochemistry , virulence , escherichia coli , chemistry , gene , medicine , pathology
Steric structure of Caf1M, a periplasmic molecular chaperone of Yersinia pestis , was reconstructed by computer modelling based on a statistically significant primary structure homology between Caf1M and PapD protein from Escherichia coli , and using the known atomic coordinates obtained by the X‐ray crystallography for PapD. In the three‐dimensional model of Caf1M an accessory sequence between F1 and G1 β‐strands (as compared to PapD) can form a strain‐specific part of the binding pocket of surface organell subunits. This accessory sequence decreases the depth of the binding pocket. The characteristic structural feature of the subfamily of periplasmic molecular chaperones with the accessory sequence (Caf1M subfamily) is the existence of exposed to a solvent Cys residues in F1 and G1 β‐strands which can form disulfide bond in the putative binding pocket. The characteristic functional feature of Caf1M subfamily is the chaperoning of more simple compositions of virulence‐associated surface organells (in the case of Y. pestis a capsule consists of only F1 protein). Highly conserved R 82 and D 93 , located at the domain surface remote from the putative subunit binding pocket, can participate in direct contacts with the conserved portion of molecular usher proteins.