Effects of calcium on biofilm formation of the bacterium Pseudoalteromonas marina and settlement of mussel Mytilus coruscus
CHANG Ruiheng1, XU Kanghao1, CAI Yushan1, YANG Jinlong1,2, LIANG Xiao1,2*
1.International Research Center for Marine Biosciences, Ministry of Science and Technology, Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China; 2.Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)，Guangzhou 511458, China
Abstract: Cell density, distribution, and thickness of Pseudoalteromonasmarina biofilms, and plantigrade settlement of the mussel Mytiluscoruscus with shell length of (0.56±0.03) mm were investigated in artificial seawater with 0, 1, 5, 20 and 50 mmol/L calcium ions (test groups) and the artificial seawater with 10 mmol/L calcium ions as control group. Extracellular polysaccharides, lipids and proteins in the biofilm were analyzed by laser scanning confocal microscope to probe into influence of different calcium ion concentrations on the biofilm formation of P.marina. The results showed that the maximal values were observed in cell density, thickness, extracellular polymeric substances, and the activity of M.coruscus plantigrade settlement induction in the biofilms formed in the 10 mmol/L calcium ion concentration. In contrast, the biomass of biofilms and plantigrade settlement were all found to be decreased in other calcium ion concentrations compared to the control. These findings indicated that the normal formation of P.marina biofilm and its plantigrade settlement induction of M.coruscus were affected by either high or low calcium ion concentrations.
2020, Vol. 35 
