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Enhanced thermotolerance and temperature-induced changes in protein composition in the hyperthermophilic archaeon ES4

Authors :
Johna . Baross
James F. Holden
Source :
Journal of Bacteriology. 175:2839-2843
Publication Year :
1993
Publisher :
American Society for Microbiology, 1993.

Abstract

The hyperthermophilic archaeon ES4, a heterotrophic sulfur reducer isolated from a deep-sea hydrothermal vent, is capable of protecting itself from thermal stress at temperatures above its optimum for growth. The thermotolerance of ES4 was determined by exposing log-phase cells to various lethal high temperatures. When ES4 was shifted from 95 to 102 degrees C, it displayed recovery from an exponential rate of death, followed by transient thermotolerance. When ES4 was shifted directly from 95 to either 105 or 108 degrees C, only exponential death occurred. However, a shift from 95 to 105 degrees C with an intermediate incubation at 102 degrees C also gave ES4 transient thermotolerance to 105 degrees C. The protein composition of ES4 was examined at temperatures ranging from 75 to 102 degrees C by one-dimensional electrophoresis. Two proteins with molecular masses of approximately 90 and 150 kDa significantly decreased in abundance with increasing growth temperature, while a 98-kDa protein, present at very low levels at normal growth temperatures (76 to 99 degrees C), was more abundant at higher temperatures. The enhanced tolerance to hyperthermal conditions after a mild hyperthermal exposure and the increased abundance of the 98-kDa protein at above-optimal temperatures imply that ES4 is capable of a heat shock-like response previously unseen in hyperthermophilic archaea.

Details

ISSN :
10985530 and 00219193
Volume :
175
Database :
OpenAIRE
Journal :
Journal of Bacteriology
Accession number :
edsair.doi.dedup.....0c6cf0017f2da009f9e4dfc163a462a7
Full Text :
https://doi.org/10.1128/jb.175.10.2839-2843.1993