iTRAQ蛋白组学分析阐明植物乳杆菌镉压力应答特征

Lactobacillus plantarum (L.plantarum) is one of commonly used probiotics. Our previous study indicated that there are significant cadmium (Cd) tolerance differences in L.plantarum. The two L.plantarum strains (Cd-tolerant strain CCFM8610 and Cd-sensitive strain CCFM191) with different Cd tolerance ability were screened out to conduct comparative proteomic analysis. The isobaric tags for relative and absolute quantitation (iTRAQ) proteomic method was adopted to elucidate characterization of Cd stress response in L.plantarum strains. Among total 1415 proteins, 206 were differentially expressed between CCFM8610 and CCFM191 under Cd-freeconditions. After Cd exposure, 27 proteins and 111 proteins were differentially regulated in CCFM8610 and CCFM191, respectively. The superior Cd tolerance ability of CCFM8610 can be attributed to the following mechanisms: specific energy metabolism and cell repair mode; superior Cd binding capacity; compact regulation on ion transportation; and enhanced biosynthesis of hydrophobic amino acids. In addition, several putative crucial proteins in Cd tolerance, including prophage P2b protein 18 (lp_2463), were identified.