Ecological functions of uncultured microorganisms in the cobaltrich ferromanganese crust of a seamount in the central Pacific are elucidated by fosmid sequencing  

作　　者：HUO Yingyi CHENG Hong Anton F.Post WANG Chunsheng JIANG Xiawei PAN Jie WU Min XU Xuewei 

机构地区：[1]Laboratory of Marine Ecosystem and Biogeochemistry, Second Institute of Oceanography, State Oceanic Administration [2]State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography [3]College of Life Sciences, Zhejiang University [4]The Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biology Laboratory [5]State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University

出　　处：《Acta Oceanologica Sinica》2015年第4期92-113,共22页海洋学报（英文版）

基　　金：China Ocean Mineral Resources R&D Association COMRA Special Foundation under contract Nos DY125-15-R-03 and DY125-13-E-01;the National Natural Science Foundation of China under contract No.41276173;the Zhejiang Provincial Natural Science Foundation of China under contract No.LQ13D060002;the Scientific Research Fund of the Second Institute of Oceanography,SOA under contract No.JT1305

摘　　要：Cobalt-rich ferromanganese is an important seafloor mineral and is abundantly present in the seamount crusts. Such crusts form potential hotspots for biogeochemical activity and microbial diversity, yet our understanding of their microbial communities is lacking. In this study, a cultivation-independent approach was used to recover genomic information and derive ecological functions of the microbes in a sediment sample collected from the cobalt-rich ferromanganese crust of a seamount region in the central Pacific. A total of 78 distinct clones were obtained by fosmid library screening with a 16S rRNA based PCR method. Proteobacteria and MGI Thaumarch-aeota dominated the bacterial and archaeal 16S rRNA gene sequence results in the microbial community. Nine fosmid clones were sequenced and annotated. Numerous genes encoding proteins involved in metabolic functions and heavy metal resistance were identified, suggesting alternative metabolic pathways and stress responses that are essential for microbial survival in the cobalt-rich ferromanganese crust. In addition, genes that participate in the synthesis of organic acids and exoploymers were discovered. Reconstruction of the metabolic pathways revealed that the nitrogen cycle is an important biogeochemical process in the cobalt-rich ferromanganese crust. In addition, horizontal gene transfer （HGT） events have been observed, and most of them came from bacteria, with some occurring in archaea and plants. Clone W4-93a, belonging to MGI Thaumarch-aeota, contained a region of gene synteny. Comparative analyses suggested that a high frequency of HGT events as well as genomic divergence play important roles in the microbial adaption to the deep-sea environment.Cobalt-rich ferromanganese is an important seafloor mineral and is abundantly present in the seamount crusts. Such crusts form potential hotspots for biogeochemical activity and microbial diversity, yet our understanding of their microbial communities is lacking. In this study, a cultivation-independent approach was used to recover genomic information and derive ecological functions of the microbes in a sediment sample collected from the cobalt-rich ferromanganese crust of a seamount region in the central Pacific. A total of 78 distinct clones were obtained by fosmid library screening with a 16S rRNA based PCR method. Proteobacteria and MGI Thaumarch-aeota dominated the bacterial and archaeal 16S rRNA gene sequence results in the microbial community. Nine fosmid clones were sequenced and annotated. Numerous genes encoding proteins involved in metabolic functions and heavy metal resistance were identified, suggesting alternative metabolic pathways and stress responses that are essential for microbial survival in the cobalt-rich ferromanganese crust. In addition, genes that participate in the synthesis of organic acids and exoploymers were discovered. Reconstruction of the metabolic pathways revealed that the nitrogen cycle is an important biogeochemical process in the cobalt-rich ferromanganese crust. In addition, horizontal gene transfer （HGT） events have been observed, and most of them came from bacteria, with some occurring in archaea and plants. Clone W4-93a, belonging to MGI Thaumarch-aeota, contained a region of gene synteny. Comparative analyses suggested that a high frequency of HGT events as well as genomic divergence play important roles in the microbial adaption to the deep-sea environment.

关 键 词：SEAMOUNT cobalt-rich ferromanganese crust METAGENOME horizontal gene transfer 

分 类 号：P744[天文地球—海洋科学]