Cloning and characterization of a gene encoding a cold-shock protein inLactobacillus casei

Abstract

One csp-like gene, called cspA, from the lactic acid bacterium Lactobacillus casei was identified by an inverse polymerase chain reaction approach based on degenerate primers. cspA encodes a protein of 66 amino acid residues, which displays at least 74% identity with Csp proteins of Lactobacillus genera. Northern blot analysis revealed that cspA is transcribed monocistronically and that its expression is induced after a temperature downshift from 37 degrees C to 20 degrees C. The transcriptional start site has been determined and is situated 98 bp upstream of the initiation codon. A cspA mutant strain was constructed and it showed reduced growth rate compared with the wild type at both optimal and low temperatures, demonstrating that CspA plays an important role in the physiology of L. casei.

The Cold Shock Response of <i>Lactobacillus casei:</i> Relation between HPr Phosphorylation and Resistance to Freeze/Thaw Cycles

“…They revealed that cspA was significantly induced by a cold shock with the highest induction occurring in cultures shifted from 37 to 10 ° C (table 2). Induction of cspA by cold shock has also recently been demonstrated by Northern blots [Sauvageot et al, 2006]. In contrast, cspB did not seem to be inducible by temperature shifts from 37 ° C to either 20 or 15 ° C, but was slightly induced at the lowest temperature tested ( table 2 ).…”

“…1 c). Recently, we cloned, sequenced and characterized a gene encoding a cold shock protein of L. casei BL23 which we named CspA LC [Sauvageot et al, 2006]. The N-terminal sequence determined for the upregulated CSP was completely identical to that deduced from the nucleotide sequence of the cspA LC gene.…”

“…Total RNA of L. casei was isolated using the RNeasy Midi kit (Qiagen) from exponentially growing cells cultivated at 37 ° C and from cultures after cold shock [Sauvageot et al, 2006]. After controlling the quality of the RNA with the Experion automated electrophoresis station (Bio-Rad Laboratories, Richmond, Calif., USA), 2 g of total RNA was reverse transcribed using the Omniscript enzyme (Qiagen) and random hexamer primers according to the manufacturer's recommendations.…”

“…During industrial processes or storage of starter cultures, lactic acid bacteria frequently encounter low or freezing temperatures. We recently cloned and characterized the cspA gene of L. casei [Sauvageot et al, 2006]. In this study, we compare the cold shock response of L. casei strain BL23 and five CCR mutants affected either in ccpA , ptsH (encoding HPr) or hprK (encoding HprK/P).…”

Enterococcus faecalis Uses a Phosphotransferase System Permease and a Host Colonization-Related ABC Transporter for Maltodextrin Uptake

“…Plasmids were extracted from E. coli by using the NucleoSpin plasmid kit (Macherey-Nagel). RNA extraction was performed as previously described (35). The 5= end of the mRNA corresponding to the mdxEFG operon (Fig.…”