Project description:Strain SM1988T is a Gram-negative, aerobic, oxidase- and catalase-positive, unipolar flagellated, and rod-shaped bacterium capable of hydrolyzing casein, gelatin and collagens. Phylogenetic analysis revealed that strain SM1988T formed a distinct phylogenetic lineage along with known genera within the family Pseudoalteromonadaceae, with 16S rRNA gene sequence similarity being less than 93.3% to all known species in the family. Based on the phylogenetic, genomic, chemotaxonomic and phenotypic data, strain SM1988T was considered to represent a novel species in a novel genus in the family Pseudoalteromonadaceae, for which the name Flocculibacter collagenilyticus gen. nov., sp. nov. is proposed, with the type strain being SM1988T (= MCCC 1K04279T = KCTC 72761T). Strain SM1988T showed a high production (236 U/mL) of extracellular collagenases, which had high activity against both bovine collagen and codfish collagen. Biochemical tests combined with genomic and secretomic analyses indicated that the collagenases secreted by strain SM1988T are serine proteases from the S8 family. These data suggest that strain SM1988T acts as an important player in marine collagen degradation and recycling and may have a promising potential in collagen resource utilization.
Project description:We compared genetic profiles of planktonic stage to biofilm stage of deep sea bacterium Pseudoalteromonas sp. SM9913 and revealed genetic features during switch from planktonic to pellicle stage in Pseudoalteromonas sp. SM9913.
Project description:Sulfur metabolism in the deep-sea cold seep has been mentioned to have an important contribution to the biogeochemical cycle of sulfur in previous studies. And sulfate reducing bacteria have also been considered to be a dominant microbial population in the deep-sea cold seep and play a crucial role in this process. However, most of sulfate reducing bacteria from cold seep still cannot be purely cultured under laboratory conditions, therefore the actual sulfur metabolism pathways in sulfate reducing bacteria from the deep-sea cold seep have remained unclear. Here, we isolate and pure culture a typical sulfate reducing bacterium Desulfovibrio marinus CS1 from the sediment sample of the deep-sea cold seep in the South China Sea, which provides a probability to understand the sulfur metabolism in the cold seep.
Project description:In the present study, we studied microbial composition and metabolic activity in the bathypelagic zone of the South China Sea. 12 samples were collected and subjected to metaproteomic analysis. Our data provide a novel view of the roles of two lifestyle prokaryotes and their link in substrate utilization in dark ocean.
Project description:The Breviatea form a lineage of free-living protists that emerged over 800 million years ago as a sister clade to opistokonta, comprising animals and fungi. Breviates conserved the ability to thrive in absence of oxygen which was an important adaptation to the low oceanic oxygen-levels that prevailed by that time. We previously found that the novel breviate, Lenisia limosa, gen. et sp. nov., was opportunistically colonized by relatives of animal-associated Arcobacter. Here we used differential proteomics to investigate how the presence/absence of symbiotic Arcobacter is manifested in Lenisia limosa's proteome. Vice versa, we also measured how symbiosis is reflected in Arcobacter's proteome. The results provide a resource to characterize the molecular underpinnings of a novel protist-prokaryote symbiosis.
Project description:Fuerstia marisgermanicae gen. nov., sp. nov., an unusual dividing bacterium from the Wadden Sea, belonging to the novel family Fuerstiaceae fam. nov., within the phylum Planctomycetes
