Metagenomic and Microscopic Analysis of Magnetotactic Bacteria in Tangyin Hydrothermal Field of Okinawa Trough

Si Chen; Min Yu; Wenyan Zhang; Kuang He; Hongmiao Pan; Kaixuan Cui; Yicong Zhao; Xiao-Hua Zhang; Tian Xiao; Wuchang Zhang; Long-Fei Wu

doi:10.3389/fmicb.2022.887136

Metagenomic and Microscopic Analysis of Magnetotactic Bacteria in Tangyin Hydrothermal Field of Okinawa Trough

Front Microbiol. 2022 Jun 10:13:887136. doi: 10.3389/fmicb.2022.887136. eCollection 2022.

Authors

Si Chen^{1

2

3

4}, Min Yu^{2

5}, Wenyan Zhang^{1

2

4

6}, Kuang He⁷, Hongmiao Pan^{1

2

4

6}, Kaixuan Cui^{1

2

3

4}, Yicong Zhao^{1

2

3

4}, Xiao-Hua Zhang^{2

5}, Tian Xiao^{1

2

4

6}, Wuchang Zhang^{1

2

4}, Long-Fei Wu^{6

8}

Affiliations

¹ CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
² Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
³ University of Chinese Academy of Sciences, Beijing, China.
⁴ Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China.
⁵ College of Marine Life Sciences, Ocean University of China, Qingdao, China.
⁶ International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, Qingdao, China.
⁷ Key Lab of Submarine Geosciences and Prospecting Techniques, Frontiers Science Center for Deep Ocean Multispheres and Earth System, MOE and College of Marine Geosciences, Ocean University of China, Qingdao, China.
⁸ Aix Marseille University, CNRS, LCB, Marseille, France.

Abstract

Magnetotactic bacteria (MTB) have been found in a wide variety of marine habitats, ranging from intertidal sediments to deep-sea seamounts. Deep-sea hydrothermal fields are rich in metal sulfides, which are suitable areas for the growth of MTB. However, MTB in hydrothermal fields have never been reported. Here, the presence of MTB in sediments from the Tangyin hydrothermal field was analyzed by 16S rRNA gene amplicon analysis, metagenomics, and transmission electron microscopy. Sequencing 16S rRNA gene yielded a total of 709 MTB sequences belonging to 20 OTUs, affiliated with Desulfobacterota, Alphaproteobacteria, and Nitrospirae. Three shapes of magnetofossil were identified by transmission electron microscopy: elongated-prismatic, bullet-shaped, and cuboctahedron. All of these structures were composed of Fe₃O₄. A total of 121 sequences were found to be homologous to the published MTB magnetosome-function-related genes, and relevant domains were identified. Further analysis revealed that diverse MTB are present in the Tangyin hydrothermal field, and that multicellular magnetotactic prokaryote (MMPs) might be the dominant MTB.

Keywords: 16S rRNA gene; hydrothermal field; magnetofossil; magnetosome genes; magnetotactic bacteria.