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Title: Proteolysis of truncated hemolysin A yields a stable dimerization interface

Abstract

Wild-type and variant forms of HpmA265 (truncated hemolysin A) fromProteus mirabilisreveal a right-handed, parallel β-helix capped and flanked by segments of antiparallel β-strands. The low-salt crystal structures form a dimeric structureviathe implementation of on-edge main-chain hydrogen bonds donated by residues 243–263 of adjacent monomers. Surprisingly, in the high-salt structures of two variants, Y134A and Q125A-Y134A, a new dimeric interface is formedviamain-chain hydrogen bonds donated by residues 203–215 of adjacent monomers, and a previously unobserved tetramer is formed. In addition, an eight-stranded antiparallel β-sheet is formed from the flap regions of crystallographically related monomers in the high-salt structures. This new interface is possible owing to additional proteolysis of these variants after Tyr240. The interface formed in the high-salt crystal forms of hemolysin A variants may mimic the on-edge β-strand positioning used in template-assisted hemolytic activity.

Authors:
; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
NCINIGMS
OSTI Identifier:
1357635
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Crystallographica. Section F, Structural Biology Communications; Journal Volume: 73; Journal Issue: 3
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Novak, Walter R. P., Bhattacharyya, Basudeb, Grilley, Daniel P., and Weaver, Todd M. Proteolysis of truncated hemolysin A yields a stable dimerization interface. United States: N. p., 2017. Web. doi:10.1107/S2053230X17002102.
Novak, Walter R. P., Bhattacharyya, Basudeb, Grilley, Daniel P., & Weaver, Todd M. Proteolysis of truncated hemolysin A yields a stable dimerization interface. United States. doi:10.1107/S2053230X17002102.
Novak, Walter R. P., Bhattacharyya, Basudeb, Grilley, Daniel P., and Weaver, Todd M. Tue . "Proteolysis of truncated hemolysin A yields a stable dimerization interface". United States. doi:10.1107/S2053230X17002102.
@article{osti_1357635,
title = {Proteolysis of truncated hemolysin A yields a stable dimerization interface},
author = {Novak, Walter R. P. and Bhattacharyya, Basudeb and Grilley, Daniel P. and Weaver, Todd M.},
abstractNote = {Wild-type and variant forms of HpmA265 (truncated hemolysin A) fromProteus mirabilisreveal a right-handed, parallel β-helix capped and flanked by segments of antiparallel β-strands. The low-salt crystal structures form a dimeric structureviathe implementation of on-edge main-chain hydrogen bonds donated by residues 243–263 of adjacent monomers. Surprisingly, in the high-salt structures of two variants, Y134A and Q125A-Y134A, a new dimeric interface is formedviamain-chain hydrogen bonds donated by residues 203–215 of adjacent monomers, and a previously unobserved tetramer is formed. In addition, an eight-stranded antiparallel β-sheet is formed from the flap regions of crystallographically related monomers in the high-salt structures. This new interface is possible owing to additional proteolysis of these variants after Tyr240. The interface formed in the high-salt crystal forms of hemolysin A variants may mimic the on-edge β-strand positioning used in template-assisted hemolytic activity.},
doi = {10.1107/S2053230X17002102},
journal = {Acta Crystallographica. Section F, Structural Biology Communications},
number = 3,
volume = 73,
place = {United States},
year = {Tue Feb 21 00:00:00 EST 2017},
month = {Tue Feb 21 00:00:00 EST 2017}
}
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