16S rDNA analysis of microbial communities in anoxic marine sediments of the Marmara Sea

Abstract

The sediments of the Marmara Sea are of importance since they are believed to have been a rather sensitive recorder of climatic, biological and chemical changes and water-mass movements in the region. In this study, overall microbial community of coastal sediments from the Marmara Sea was characterized by cloning and sequencing of 16S rRNA genes. Denaturing Gradient Gel Electrophoresis was used to investigate the seasonal distribution of the microbial communities in coastal sediments from Tuzla and Moda. The sequencing of clone libraries revealed a higher microbial diversity in anoxic sediment samples of Tuzla than that of derived from Moda. and served to understand the potential dominant metabolic processes prevailing under anoxic conditions. Methylotrophic methanogenesis and denitrification were found as the potential dominant metabolic processes in Tuzla sediments, whereas hydrogenotrophic methanogenesis and fermentation appeared to be the potential dominant metabolic processes in Moda sediments. DGGE data revealed a more significant seasonal change in microbial community structure of Tuzla sediments.|Keywords: Marmara Sea, Anoxic Marine Sediments, 16S rDNA, Microbial Diversity, Clone Library