title: Characteristics of the cultivable bacteria from sediments associated with two deep-sea hydrothermal vents in Okinawa Trough.
abstract: In this study, different culture-dependent methods were used to examine the cultivable heterotrophic bacteria in the sediments associated with two deep-sea hydrothermal vents (named HV1 and HV2) located at Iheya Ridge and Iheya North in Okinawa Trough. The two vents differed in morphology, with HV1 exhibiting diffuse flows while HV2 being a black smoker with a chimney-like structure. A total of 213 isolates were identified by near full-length 16S rRNA gene sequence analysis. Of these isolates, 128 were from HV1 and 85 were from HV2. The bacterial community structures were, in large parts, similar between HV1 and HV2. Nevertheless, differences between HV1 and HV2 were observed in one phylum, one class, 4 orders, 10 families, and 20 genera. Bioactivity analysis revealed that 25 isolates belonging to 9 different genera exhibited extracellular protease activities, 21 isolates from 11 genera exhibited extracellular lipase activities, and 13 isolates of 8 genera displayed antimicrobial activities. This is the first observation of a large population of bacteria with extracellular bioactivities existing in deep-sea hydrothermal vents. Taken together, the results of this study provide new insights into the characteristics of the cultivable heterotrophic bacteria in deep-sea hydrothermal ecosystems.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.|University of Chinese Academy of Sciences, Beijing, China.
authors.forename: Qing-lei
authors.initials: QL
authors.lastname: Sun
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
authors.forename: Ming-qing
authors.initials: MQ
authors.lastname: Wang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China. lsun@qdio.ac.cn.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China. lsun@qdio.ac.cn.|Collaborative Innovation Center of Deep Sea Biology, Zhejiang University, Hangzhou, China. lsun@qdio.ac.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Sun
mesh_terms: D000890:Anti-Infective Agents / Q000032:analysis; D001419:Bacteria / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification*; D044822:Biodiversity; D017753:Ecosystem; D019015:Geologic Sediments / Q000382:microbiology; D052836:Heterotrophic Processes; D060086:Hydrothermal Vents / Q000382:microbiology*; D007564:Japan; D008049:Lipase / Q000032:analysis; D010447:Peptide Hydrolases / Q000032:analysis; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*
chemical_list: D000890:Anti-Infective Agents; D012336:RNA, Ribosomal, 16S; D008049:Lipase; D010447:Peptide Hydrolases
keywords: Antimicrobial; Cultivable bacteria; Deep-sea hydrothermal vent; Lipase; Protease; Sediment