TY - JOUR
T1 - Constitutive expression of small heat shock protein in an htpG disruptant of the cyanobacterium Synechococcus sp. PCC 7942
AU - Kojima, Kouji
AU - Nakamoto, Hitoshi
PY - 2005/5/1
Y1 - 2005/5/1
N2 - In cyanobacteria, a disruptant of hspA encoding a small heat shock protein homologue, shows decreased cell growth rates at moderately high temperatures, and loss of both basal and acquired thermo-tolerances, which resemble the phenotype of an htpG disruptant. In vitro studies have shown that both small heat shock protein and Hsp90 can bind and keep non-native proteins in a refolding-competent state under denaturing conditions. The aim of the present study is to elucidate whether constitutive expression of HspA can functionally replace HtpG, a prokaryotic homolog of Hsp90, in the cyanobacterium Synechococcus sp. PCC 7942. HspA did not improve the viability of the htpG disruptant at a lethal temperature, although it did that of the wild type. It did not improve an iron-starved phenotype of the mutant under normal growth conditions, a novel phenotype found in the present study. These results suggest that cellular function of HtpG may differ significantly from that of HspA.
AB - In cyanobacteria, a disruptant of hspA encoding a small heat shock protein homologue, shows decreased cell growth rates at moderately high temperatures, and loss of both basal and acquired thermo-tolerances, which resemble the phenotype of an htpG disruptant. In vitro studies have shown that both small heat shock protein and Hsp90 can bind and keep non-native proteins in a refolding-competent state under denaturing conditions. The aim of the present study is to elucidate whether constitutive expression of HspA can functionally replace HtpG, a prokaryotic homolog of Hsp90, in the cyanobacterium Synechococcus sp. PCC 7942. HspA did not improve the viability of the htpG disruptant at a lethal temperature, although it did that of the wild type. It did not improve an iron-starved phenotype of the mutant under normal growth conditions, a novel phenotype found in the present study. These results suggest that cellular function of HtpG may differ significantly from that of HspA.
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U2 - 10.1007/s00284-005-4486-9
DO - 10.1007/s00284-005-4486-9
M3 - Article
C2 - 15886908
AN - SCOPUS:21044459355
VL - 50
SP - 272
EP - 276
JO - Current Microbiology
JF - Current Microbiology
SN - 0343-8651
IS - 5
ER -