Affordable Access

Structural distribution of stability in a thermophilic enzyme.

Authors
  • Hollien, J
  • Marqusee, S
Type
Published Article
Journal
Proceedings of the National Academy of Sciences of the United States of America
Publication Date
Nov 23, 1999
Volume
96
Issue
24
Pages
13674–13678
Identifiers
PMID: 10570131
Source
Medline
License
Unknown

Abstract

Stability parameters for individual residues in Thermus thermophilus cysteine-free RNase H were determined by native state hydrogen exchange, thus providing a unique comparison of regional thermodynamics between thermophilic and mesophilic homologues. The general distribution of stability in the thermophilic protein is similar to that of its mesophilic homologue, with a proportional increase in stability for almost all residues. As a consequence, the residue-specific stabilities of the two proteins are remarkably similar under conditions where their global stabilities are the same. These results indicate that T. thermophilus RNase H is stabilized in a delocalized fashion, preserving a finely tuned balance of stabilizing interactions throughout the structure. Therefore, although protein stability can be altered by single amino acid substitution, evolution for optimal function may require more subtle and delocalized mechanisms.

Report this publication

Statistics

Seen <100 times