Functional proteomics and correlated signaling pathway of the thermophilic bacterium Bacillus stearothermophilus TLS33 under cold-shock stress

Abstract

The thermophilic bacterium Bacillus stearothermophilus TLS33 was examined under cold-shock stress by a proteomic approach to gain a better understanding of the protein synthesis and complex regulatory pathways of bacterial adaptation. After downshift in the temperature from 65 degrees C, the optimal growth temperature for this bacterium, to 37 degrees C and 25 degrees C for 2 h, we used the high-throughput techniques of proteomic analysis combining 2-DE and MS to identify 53 individual proteins including differentially expressed proteins. The bioinformatics database was used to search the biological functions of proteins and correlate these with gene homology and metabolic pathways in cell protection and adaptation. Eight cold-shock-induced proteins were shown to have markedly different protein expression: glucosyltransferase, anti-sigma B (sigma(B)) factor, Mrp protein homolog, dihydroorthase, hypothetical transcriptional regulator in FeuA-SigW intergenic region, RibT protein, phosphoadenosine phosphosulfate reductase and prespore-specific transcriptional activator RsfA. Interestingly, six of these cold-shock-induced proteins are correlated with the signal transduction pathway of bacterial sporulation. This study aims to provide a better understanding of the functional adaptation of this bacterium to environmental cold-shock stress.

Specific Features of the Proteomic Response of Thermophilic Bacterium Geobacillus icigianus to Terahertz Irradiation

“…The adaptation of G. icigianus to extreme environmental conditions makes its proteins difficult to isolate and separate during a proteomic analysis [ 69 , 70 , 71 ]. For the two-dimensional electrophoresis of proteins from thermophilic bacteria, a technique was developed by taking into account the difficulties with the separation of such bacterial proteins.…”

Functional and Structural Analysis of Bacillus Proteome

“…It was observed that after the temperature downshift from 65°C to 37 ° or 25°C for 2 h, six cold shock-induced proteins were markedly expressed under cold stress, such as glucosyltransferase (TagE), anti-sigma B factor (RsbT), Mrp protein homolog (MrpA), dihydroorthase (PyrC), hydroadenosine phosphosulfate reductase (YbbB) and prespore specific transcriptional activator RsfA (RsfA), whose encoded genes were correlated with the sporulation signaling pathway as shown in Fig. 7A (Topanurak et al, 2005). It was also found that the regulation of this bacterial cell under cold shock could be divided to 2 routes of activation (RsbT, TagE, YbbB and RsbT) and deactivation (MrpA and PyrC).…”