Cold Shock Protein Genes of Antarctic Streptomyces sp. AA8321

Abstract

Cold shock protein (csp) genes were cloned from cryotolerent Streptomyces sp. AA8321 isolated from soil of the Antarctic coast. More then 80% of the organism is living below 5℃ in the earth. Such as low temperature, cold stress induced specific sets of proteins, among which cold shock proteins are small and acidic proteins. Cold shock proteins are essential for cellular growth and for efficient protein synthesis at both optimal and low temperatures. We isolated three csp genes from Streptomyces sp. AA8321: csp-1, csp-2 and csp-3. They were amplified by PCR and cloned into pCR 2.1-TOPO vector. The sequence size of csp-1 & csp-2 was 195 bp, and they contained ORFs with 65 amino acids sharing significant homology to the previously reported cold shock proteins. The sequence size of csp-3 was 204 bp containing an ORF with 68 amino acids that showed very unique sequence sharing low level of homology with other cold shock proteins. This csp-3 is supposed to be a new type of csp gene.