title: Proteomic analysis of protein expression in Lactobacillus plantarum in response to alkaline stress.
abstract: Lactobacillus plantarum, a probiotic organism that plays an important role in the microbial fermentation of alkaline materials in fermenting foods, faces alkaline stress during the fermentation process. Here, we report the patterns of protein expression in L. plantarum subjected to transient (1h) alkaline stress at pH 7.7, 8.7 or 9.7. Thirty-three alkaline-responsive proteins were identified by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Identification of proteins showing differential expression in response to alkaline stress revealed that the alkaline stress response of L. plantarum is a complex process. Some proteins appear to be induced, others repressed. These proteins could be clustered into nine groups based on their probable functions: energy metabolism, transport system, purine/pyrimidine metabolism, amino acid metabolism, proteolytic activity, transcription-translation, stress-related, general function, and unknown functions. These proteomic analyses are expected to prove useful in understanding the adaptive response of L. plantarum strains to alkaline stress and may facilitate future investigations into the genetic and physiological aspects of this response.
authors.affiliation: Department of Biotechnology, SongDo Techno Park, 6F 7-50 Songdo-Dong, Yeonsu-Gu, Incheon 406-840, Republic of Korea. klee02@empal.com
authors.forename: KiBeom
authors.initials: K
authors.lastname: Lee
authors.forename: Beom-Seop
authors.initials: BS
authors.lastname: Rho
authors.forename: KyungBae
authors.initials: K
authors.lastname: Pi
authors.forename: Ho-Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Yun-Jaie
authors.initials: YJ
authors.lastname: Choi
mesh_terms: D000468:Alkalies / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D048191:Lactiplantibacillus plantarum / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism*; D053858:Metabolic Networks and Pathways / Q000187:drug effects; D014176:Protein Biosynthesis / Q000187:drug effects; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D000468:Alkalies; D001426:Bacterial Proteins