Proteomic analysis of Lactobacillus casei in response to different pHs using two-dimensional electrophoresis and MALDI TOF mass spectroscopy

Background and Objectives: Lactobacillus casei, an acid-resistant bacterium, has a protective role against the pathogens. So we aimed to determine the proteome of Lactobacillus casei ATCC39392 strain in response to different pHs of 5 and 7 using proteomic analysis. Materials and Methods: Supernatant and bacterial extraction of Lactobacillus casei ATCC39392 adapts at pHs 5 and 7 were isolated using sodium dodecyl sulfate–polyacrylamide gel and two-dimensional gel electrophoresis. The comparison of results showed that 7 protein spots were seen in pH 5 but not in pH 7. Afterward, they were excised and sent for Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) to be identified. Results: Seven different proteins (four secretory and three structural) with different roles in human body health were identified. Prescribed proteins include putative cell wall associated Hydrolase, Glycoside Hydrolase, beta-N-Acetyl hexosaminidase, Histidine Kinase, Chaperonin, metal dependent Hydrolase and Lysozyme. Conclusion: Seven isolated proteins with anti-cancer and digestive impresses are proper subjects in therapy or drug delivery approaches especially oral drug usage for protection against stomach acidic area.