Family of the major cold-shock protein, CspA (CS7.4), of Escherichia coli, whose members show a high sequence similarity with the eukaryotic Y-box binding proteins.
The cspA is a gene of Escherichia coli, whose expression is specifically induced at low temperatures to a level of 13% of total protein synthesis. The CspA protein consisting of 70 amino acid residues has high sequence similarity with eukaryotic Y-box DNA-binding proteins. We found two independent clones from the Kohara miniset phage collection, which hybridized with a DNA fragment containing cspA. DNA sequencing of these clones confirmed that the two genes are highly homologous to cspA. One designated cspB is mapped at 35 min on the E. coli chromosome and encodes a 71-residue protein with 79% identity to CspA, while the other, cspC, is mapped at 40 min and encodes a 69-residue protein with 70% identity. In addition, a DNA sequence upstream of the clpA gene at 19 min published elsewhere contains an open reading frame for a 74-residue protein with 45% identity to CspA. All csp genes were fused in the coding regions with the lacZ gene, and the expression of beta-galactosidase was examined for these hybrid genes upon cold shock. A similar cold-shock induction to cspA was observed for cspB but not cspC and cspD. These results indicate that E. coli has a family of the cspA gene, some of which are induced by cold shock.
Department of Biochemistry, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway 08854.
S J
SJ
Lee
A
A
Xie
W
W
Jiang
J P
JP
Etchegaray
P G
PG
Jones
M
M
Inouye
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003080:Cold Temperature; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D016366:Open Reading Frames; D011993:Recombinant Fusion Proteins; D012045:Regulatory Sequences, Nucleic Acid; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D015003:Yeasts / Q000235:genetics
D001426:Bacterial Proteins; C088099:CspC protein, bacteria; C088098:CspD protein, bacteria; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D011993:Recombinant Fusion Proteins; C062260:cold shock protein CS7.4, Bacteria; C490241:cspC protein, E coli; C490240:cspH protein, E coli