Secretome analysis of alkaliphilic bacterium Bacillus lehensis G1 in response to pH changes.

Bacillus lehensis G1 is an alkaliphilic bacterium that is capable of surviving in environments up to pH 11. Secretome related to bacterial acclimation in alkaline environment has been less studied compared to cytoplasmic and membrane proteome. The aim of this study was to gain better understanding of bacterial acclimation to alkaline media through analyzing extracellular proteins of B. lehensis. The pH range for B. lehensis growth was conducted, and two-dimensional electrophoresis and MALDI-TOF/TOF MS analysis were conducted to characterize changes in protein profiling in B. lehensis cultured at pH 8 and pH 11 when compared with those cultured at pH 10 (optimal growth pH). B. lehensis could grow well at pH ranging from 8 to 11 in which the bacteria showed to posses thinner flagella at pH 11. Proteomic analyses demonstrated that five proteins were up-regulated and 13 proteins were down-regulated at pH 8, whereas at pH 11, 14 proteins were up-regulated and 8 were down-regulated. Majority of the differentially expressed proteins were involved in the cell wall, main glycolytic pathways, the metabolism of amino acids and related molecules and some proteins of unknown function. A total of 40 differentially expressed protein spots corresponding to 33 proteins were identified; including GlcNAc-binding protein A, chitinase, endopeptidase lytE, flagellar hook-associated proteins and enolase. These proteins may play important roles in acclimation to alkaline media via reallocation of cell wall structure and changes to cell surface glycolytic enzymes, amino acid metabolism, flagellar hook-associated proteins and chaperones to sustain life under pH-stressed conditions.

Data for proteome analysis of Bacillus lehensis G1 in starch-containing medium.

Bacillus lehensis G1 is a cyclodextrin glucanotransferase (CGTase) producer, which can degrade starch into cyclodextrin. Here, we present the proteomics data of B. lehensis cultured in starch-containing medium, which is related to the article "Proteome-based identification of signal peptides for improved secretion of recombinant cyclomaltodextrin glucanotransferase in Escherichia coli" (Ling et. al, in press). This dataset was generated to better understand the secretion of proteins involved in starch utilization for bacterial sustained growth. A 2-DE proteomic technique was used and the proteins were tryptically digested followed by detection using MALDI-TOF/TOF. Proteins were classified into functional groups using the information available in SubtiList webserver (http://genolist.pasteur.fr/SubtiList/).

Genome sequence of Pichia kudriavzevii M12, a potential producer of bioethanol and phytase.

A draft genome sequence of Pichia kudriavzevii M12 is presented here. The genome reveals the presence of genes encoding enzymes involved in xylose utilization and the pentose phosphate pathway for bioethanol production. Strain M12 is also a potential producer of phytases, enzymes useful in food processing and agriculture.