Here we present the complete genome sequence of Siansivirga zeaxanthinifaciens CC-SAMT-1T, a flavobacterium isolated from coastal surface seawater. A 3.3Mb genome revealed remarkable specialization of this bacterium particularly in the degradation of sulfated polysaccharides available as detritus or in dissolved phase. Besides utilizing high molecular weight organic biopolymers, this strain appears to accomplish assimilatory sulfate reduction, sulfide oxidation, and acquisition and inter-conversion of inorganic carbon. Genes encoding zeaxanthin and three different kinds of DNA photolyase/cryptochrome (senses blue light) were present, while genes that code for blue light sensing BLUF domain proteins and red/far-red light sensing phytochromes were absent. Furthermore, CC-SAMT-1T lacked the rhodopsin photosystem and all other genes that confer any other known forms of phototrophy. The genomic data revealed that CC-SAMT-1T is highly adapted to sulfur-rich coastal environments, where it most likely contributes to marine carbon and sulfur cycles by metabolizing sulfated polysaccharides as well as inorganic sulfur.
Journal: Marine genomics