Proteomic analysis of log to stationary growth phaseLactobacillus plantarum cells and a 2-DE database

Abstract

Lactobacillus plantarum is part of the natural microbiota of many food fermentations as well as the human gastro-intestinal tract. The cytosolic fraction of the proteome of L. plantarum WCFS1, whose genome has been sequenced, was studied. 2-DE was used to investigate the proteins from the cytosolic fraction isolated from mid- and late-log, early- and late-stationary phase cells to generate reference maps of different growth conditions offering more knowledge of the metabolic behavior of this bacterium. From this fraction, a total of 200 protein spots were identified by MALDI-MS and a proteome production map was constructed to facilitate further studies such as detection of suitable biomarkers for specific growth conditions. More than half (57%) of the identified proteins were predicted to be involved in metabolic pathways of the bacterium. The protein profile changed during the growth of the bacteria such that 29% of the identified proteins involved in anabolic pathways were at least twofold up-regulated throughout the mid- and late-exponential and early-stationary phases. In the late-stationary phase, six proteins involved in stress or with a potential role for survival during starvation were up-regulated significantly.

Comparative Study of Sugar Fermentation and Protein Expression Patterns of Two Lactobacillus plantarum Strains Grown in Three Different Media

“…Proteomic analysis was, therefore, chosen to check the changes on the metabolic routes of two L. plantarum strains of different origin, grown in two media of diverse composition or in a standard rich medium (MRS broth). The bacteria were collected at the exponential phase, during which the metabolism indicated by the soluble proteome is most versatile, as shown in previous studies (4,9). Sugar metabolism.…”

“…In our previous study of the growth phase-dependent proteomes of L. plantarum strains REB1 and MLBPL1 grown in MRS broth, the growth phase-dependent preferential expression of the different metabolic pathways was elucidated (9). A similar study has also been performed with L. plantarum WCFS1 grown in MRS broth (4). Summing up the general findings of these two studies, the bacteria created a pool of acetyl phosphate and nucleotides during the lag phase and activated a stress response; during the early exponential phase, the bacteria showed preferential expression of proteins for the simultaneous use of different carbohydrates; during the late exponential and early stationary phases, the bacteria showed preferential expression for enzymes involved in the biosynthesis of proteins and cell division pathways and for membrane proteins; and during the late stationary phase, preferential expression was shown for numerous stress proteins (4,9).…”

“…A similar study has also been performed with L. plantarum WCFS1 grown in MRS broth (4). Summing up the general findings of these two studies, the bacteria created a pool of acetyl phosphate and nucleotides during the lag phase and activated a stress response; during the early exponential phase, the bacteria showed preferential expression of proteins for the simultaneous use of different carbohydrates; during the late exponential and early stationary phases, the bacteria showed preferential expression for enzymes involved in the biosynthesis of proteins and cell division pathways and for membrane proteins; and during the late stationary phase, preferential expression was shown for numerous stress proteins (4,9). The indicated simultaneous use of different carbohydrates in the early exponential phase was very interesting because these results contradict the standard view of carbohydrate metabo-lism in LAB, according to which, glucose represses the proteins associated with the metabolism of other sugars (8,22).…”

Lactobacillus plantarum response to inorganic carbon concentrations: PyrR2-dependent and -independent transcription regulation of genes involved in arginine and nucleotide metabolism

“…In contrast, the abundance of the proteins involved in UMP and GMP synthesis (pyr genes, guaA and guaB), in glycerol metabolism (Dak2), in glutamine import (GlnQ1 and GlnQ3) and arginine synthesis or incorporation (ArgS or ArgH) decreased when growth rate was optimal. A recent proteomic study of L. plantarum has identified regulated proteins in stationary phase as compared to the exponential phase (Cohen et al, 2006). Among genes encoding Icr proteins, ten were found to be upregulated in stationary phase.…”

Characterization of surface molecules from bacterial cells involved in the potential probiotic activity of natural lactobacilli isolates

“…Po jednom od predloženih mehanizama, na nižoj temperaturi postoji više izoprenoidnih glikozil lipid nosača koji se ne koriste za sintezu ćelijskog zida, jer bakterije sporije rastu, tako da su ovi molekuli na raspolaganju za biosintezu EPS-a (Sutherland, 1972). plantarum WCFS1 napomenuli da ne produkuje EPS jer mu nedostaju regulatorni geni (Cohen et al, 2006). Ipak, treba sa rezervom prihvatiti sve informacije koje mogu da se zaključe na osnovu homologije sa sekvenciranim genomima, jer su moguće greške pri sekvenciranju i bionformatičkim analizama dobijenih sekvenci.…”