The diverse bacterial community in Sapelo Island and study on the pathway of DMSP degradation in marine bacteria

Abstract

Salt marshes/estuarine systems are one of the most biologically productive ecosystems on the planet. In this study, further analyses examined the diversity of the bacterial community in a salt marsh/estuarine ecosystem in the southeastern coast of the US. The study on bacterioplankton has been considered very important because prokaryotes are essential components of the oceanic food web and catalyze many major biogeochemical processes in the sea. Different methods to collect bacterioplankton samples from seawater may have effect on microarrays result. A whole genome microarray of Silicibacter pomeroyi DSS3 was analyzed as a standard to indicate the expression of collected seawater sample through different methods of collection. Silicibacter pomeroyi, a member of a marine roseobacter clade, is a model system for the study of dimethylsulfoniopropionate (DMSP) metabolism. The degradation of DMSP occurs through two competing pathways, known as the cleavage and the demethylation pathways. Bioinformatics approaches were used to identify candidate genes for enzymes involved in DMSP degradation. A genetic system was applied to test the function of these genes. The growth of mutants with different carbon source was also measured.