ARCHAEAL COLD-ADAPTED PROTEINS - STRUCTURAL AND EVOLUTIONARY ANALYSISOF THE ELONGATION-FACTOR-2 PROTEINS FROM PSYCHROPHILIC, MESOPHILIC AND THERMOPHILIC METHANOGENS

Citation
T. Thomas et R. Cavicchioli, ARCHAEAL COLD-ADAPTED PROTEINS - STRUCTURAL AND EVOLUTIONARY ANALYSISOF THE ELONGATION-FACTOR-2 PROTEINS FROM PSYCHROPHILIC, MESOPHILIC AND THERMOPHILIC METHANOGENS, FEBS letters, 439(3), 1998, pp. 281-286
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biology,"Cell Biology",Biophysics
Journal title
ISSN journal
0014-5793
Volume
439
Issue
3
Year of publication
1998
Pages
281 - 286
Database
ISI
SICI code
0014-5793(1998)439:3<281:ACP-SA>2.0.ZU;2-D
Abstract
To identify structural features important for low temperature activity in archaeal proteins, elongation factor 2 (EF-2) genes (aef2) were se quenced from psychrophilic, mesophilic and thermophilic methanogens. S catter plots were used to compare evolutionary distances for EF-2 amin o acid sequences vs. 16S-rRNA sequences from methanogens growing at di verse temperatures. The absence of a temperature bias for the rate of protein vs. nucleic acid evolution demonstrated the importance of comp aring closely related proteins in order to identify changes indicative of thermal adaptation. Three-dimensional modelling of the new EF-2 se quences enabled the identification of amino acid residues that may be important for conferring low temperature activity and included greater structural flexibility produced ba fewer salt bridges, less packed hy drophobic cores and the reduction of proline residues in loop structur es. (C) 1998 Federation of European Biochemical Societies.