Inhibitory mechanism of lectin(MCL-T)against Shewanella putrefaciens in Manila clam Ruditapes philippinarum by proteomics approach
YANG Qingqing, JIN Yiwen, LI Wei, ZHAO Fei, KONG Liang, TONG Changqing
1.College of Food Science and Engineering, Dalian Ocean University, Dalian 116023, China; 2.College of Marine Science and Environment, Dalian Ocean University, Dalian 116023, China
Abstract: In order to investigate the mechanism of lectin(MCL-T)secretion of Manila clam Ruditapesphilippinarum induced by Shewanellaputrefaciens and inhibitory effect of the lectin against S.putrefaciens, freeze-dried powder of the MCL-T was in the sea water of Manila clam with body mass of(8±1)g injected with S.putrefaciens at feed muscles at a dose of 0.5, 1.0, 1.5, 2.0, and 2.5 OD600 nm and reared in clean 300 mL enamel trays of each 20 cm×25 cm×4.5 cm at water temperature of(22±3)℃ in 12, 24 h, and 36 h by solid phase assay analyzing the reaction of MCL-T with S.putrefaciens outer membrane proteins(OMP), immersion of Manila clam in group 7 and without any treatment of the clam in group 1.OD600 nm values were measured in diluted sterile TSB culture medium of S.putrefaciens containing freeze-dried powder of the MCL-T at a dose of 0, 0.01, 0.1, and 1.0 mg/L for 24 h to detect inhibitory effect of MCL-T on S.putrefaciens.The expression of the proteome in S.putrefaciens with MCL-T was analyzed by label-free quantitative proteomics.The results showed that there was more yield of MCL-T in the injection groups than that in the immersion group, with concentration-dependence of MCL-T binding to S.putrefaciens OMP.A total of 74 differential proteins were identified in expression profiles of S.putrefaciens with MCL-T compared with without MCL-T.The expression of 16 proteins was found to be up-regulated and 58 proteins down-regulated.These differentially expressed proteins mainly involved in the amino acid biosynthetic pathway, pyruvate metabolism, citric acid cycle, aminoacyl-tRNA biosynthesis pathway and carbon metabolism pathway.Therefore, MCL-T inhibited S.putrefaciens by disturbing amino acid biosynthesis, pyruvate metabolism and citric acid cycle.
2021, Vol. 36 
