The truncated form of the bacterial heat shock protein ClpB/HSP100 contributes to development of thermotolerance in the cyanobacterium Synechococcus sp. strain PCC 7942.
ClpB is a highly conserved heat shock protein that is essential for thermotolerance in bacteria and eukaryotes. One distinctive feature of all bacterial clpB genes is the dual translation of a truncated 79-kDa form (ClpB-79) in addition to the full-length 93-kDa protein (ClpB-93). To investigate the currently unknown function of ClpB-79, we have examined the ability of the two different-sized ClpB homologues from the cyanobacterium Synechococcus sp. strain PCC 7942 to confer thermotolerance. We show that the ClpB-79 form has the same capacity as ClpB-93 to confer thermotolerance and that the ClpB-79 protein contributes ca. one-third of the total thermotolerance developed in wild-type Synechococcus, the first in vivo demonstration of a functional role for ClpB-79 in bacteria.
Clarke
A K
AK
Umeå Plant Sciences Centre, Department of Plant Physiology, University of Umeâ, Umeâ S-901 87, Sweden. Adrian.Clarke@plantphys.umu.se
Eriksson
M J
MJ
D000458:Cyanobacteria / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D049071:Endopeptidase Clp; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018869:Heat-Shock Response; D016297:Mutagenesis, Site-Directed; D013696:Temperature
D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D049071:Endopeptidase Clp; C069775:ClpB protein, E coli