Preliminary Proteomics Analysis Of Lactobacillus Plantarum

Lactobacillus plantarum distributed broadly in natural environment, especially in the fermented food. L. plantarum can improve the flavor and quality of the fermented food, inhibit the growth of pathogens, prevent or treat diarrhea and constipation, and improve the balance of microorganism ecology in gastrointestinal tract. Up to date, there is limited knowledge about the probotic functions as well as the componence of proteins of L. plantarum in molecule level. Therefore, it is very important to analyze the whole proteome of the L. plantarum.In this research, proteins from the whole-cell and the culture supernatant of L. plantarum were separated by two-dimensional gel electrophoresis and BN/SDS-PAGE electrophoresis to construct proteomic reference maps. Protein spots were excised from gels, in-gel digested and then identified by using MALDI-TOF/TOF with Mascot search program, searching protein message in database of L. plantarum JDM1. A total of 429 proteins were identified. The main results was shown as following,1.2-DE map with pH 3.5-10 of the whole-cell proteins of L. plantarum was merged by different pH gradient 2-DE maps. A total of 725 spots excised and 603 spots were identified representing 412 proteins, including 122 unexplained hypothetical proteins.2.2-DE map with pH 3-11 of the secretary proteins of L. plantarum was builded. A total of 28 spots were identified representing 22 proteins, including 22 hypothetical proteins.3. BN/SDS-PAGE electrophoresis method was used to separate protein complexes. A total of 51 proteins were identified, including 6 proteins not identified in 2-DE map of the whole-cell proteins. Interestingly, a novel protein complex composed of Map3 and Map2 was identified in this study.In this study, characteristics of the expression of proteins in the late logarithmic growth of L. Plantarum was analyzed. Therefore, the reseach work will provide some new research strategies for ascertaining the probiotic functions and further genetical modification of L. plantarum.