Lipids and their delta C-13 values reveal carbon assimilation and cycling in the methane-seep tubeworm Paraescarpia echinospica from the South China Sea

doi:10.1016/j.dsr.2021.103556

	Lipids and their delta C-13 values reveal carbon assimilation and cycling in the methane-seep tubeworm Paraescarpia echinospica from the South China Sea
	Guan, Hongxiang 2,3,4; Birgel, Daniel 5; Feng, Dong 6; Peckmann, Joern 5; Liu, Lei 2,3; Liu, Lihua 4; Tao, Jun 1
刊名	DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
	2021-08-01
卷号	174 页码:12
关键词	Tubeworms Fatty acids Delta delta C-13 Sterols South China Sea
ISSN号	0967-0637
DOI	10.1016/j.dsr.2021.103556
通讯作者	Guan, Hongxiang(guanhx@giec.ac.cn)
英文摘要	Gutless tubeworms obtain their nutrition from their bacterial endosymbiotic partners, and the metazoan hosts provide the bacteria with sulfide, carbon dioxide, and molecular oxygen taken up through the plume. At seeps, tubeworms take up sulfide using their posterior end, allowing them to fix carbon dioxide and synthesize organic molecules. Compared to bulk tissue isotope compositions, lipid biomarkers and their compound-specific delta C-13 values of soft tissues allow to assign nutritional modes of endosymbionts and hosts, as well as associations be-tween endosymbionts and the animal host. In this study, the tubeworm Paraescarpia echinospica retrieved from the Haima seeps in the South China Sea (SCS) at approximately 1400 m water depth was analyzed using 16S rRNA, bulk tissue isotopes, lipid biomarkers, and compound-specific delta C-13 values. The Lamellibrachia sp. endo-symbiont, a phylotype of the Gammaproteobacteria, is a bacterium gaining energy from oxidizing sulfur com-pounds (thiotrophic endosymbiont). Further, six phylotypes of Gammaproteobacteria and seven phylotypes of Alphaproteobacteria were identified in the trophosome. High contents of n-C-16:1 omega 7, n-C-18:1 omega 7 fatty acids, and n-C-16:0 and n-C-18:1 omega 7 fatty alcohols were found in the trophosome, and somewhat lower contents in the plume and vestimentum, consistent with the prevalence of thiotrophic endosymbionts in the trophosome. The fatty acids n-C-16:1 omega 7 and n-C-18:1 omega 7 produced by the endosymbionts yielded delta C-13 values ranging from -34 parts per thousand to -30 parts per thousand, reflecting the use of marine dissolved inorganic carbon (DIC) rather than DIC derived from anaerobic oxidation of methane. The overall small differences in delta C-13 values (Delta(among tissues) <= 3 parts per thousand) for n-C-16:1 omega 7 and n-C-18:1 omega 7 fatty acids in both symbiont-containing and symbiont-free tissues appear to represent the delta C-13 signatures of the endo-symbionts. Generally, n-C-16:1 omega 7 and n-C-18:1 omega 7 fatty acids should be more C-13-depleted than the respective n-C-16:0, n-C-18:0 fatty acids resulting from desaturation. However, in this study, the saturated n-C-16:0, n-C-18:0 fatty acids in soft tissues were C-13 depleted by 4 parts per thousand-10 parts per thousand compared to the respective n-C-16:1 omega 7 and n-C-18:1 omega 7 fatty acids, sug-gesting complex trophic interactions between P. echinospica, its endosymbionts, other bacteria living in P. echinospica, and the environment. Sterols, yielding the lowest delta C-13 values from-49 parts per thousand to-46 parts per thousand, are inter-preted to be derived from bioconversion of dietary sterols by the animal host. The combination of microbial diversity, bulk tissue isotopes, and lipid biomarkers used here is a valuable approach to evaluate the nutritional associations between symbionts and hosts in chemosymbiosis as well as the diet of the animal host.
资助项目	National Key R&D Program of China[2018YFC0310005] ; NSF of China[91958105] ; Major Program of Guangdong Basic and Applied Research[2019B030302004]
WOS关键词	POLYUNSATURATED FATTY-ACIDS ; ISOTOPIC FRACTIONATION ; BIOMARKER PATTERNS ; COLD SEEPS ; CHEMOAUTOTROPHIC ENDOSYMBIONTS ; FORMATION ENVIRONMENTS ; AUTHIGENIC CARBONATES ; STEROL BIOSYNTHESIS ; MUSSELS ; BACTERIA
WOS研究方向	Oceanography
语种	英语
出版者	PERGAMON-ELSEVIER SCIENCE LTD
WOS记录号	WOS:000696313600001
资助机构	National Key R&D Program of China ; NSF of China ; Major Program of Guangdong Basic and Applied Research
内容类型	期刊论文
源URL	[http://ir.giec.ac.cn/handle/344007/33887]
专题	中国科学院广州能源研究所
通讯作者	Guan, Hongxiang
作者单位	1.Guangzhou Marine Geol Survey, MLR Key Lab Marine Mineral Resources, Guangzhou 510075, Peoples R China 2.Ocean Univ China, Frontiers Sci Ctr Deep Ocean Multispheres & Earth, Key Lab Submarine Geosci & Prospecting Tech, MOE, Qingdao 266100, Peoples R China 3.Ocean Univ China, Coll Marine Geosci, Qingdao 266100, Peoples R China 4.Chinese Acad Sci, Guangzhou Inst Energy Convers, Key Lab Gas Hydrate, Guangzhou 510640, Peoples R China 5.Univ Hamburg, Ctr Erdsyst Forsch & Nachhaltigkeit, Inst Geol, D-20146 Hamburg, Germany 6.Shanghai Ocean Univ, Coll Marine Sci, Shanghai Engn Res Ctr Hadal Sci & Technol, Shanghai 201306, Peoples R China
推荐引用方式 GB/T 7714	Guan, Hongxiang,Birgel, Daniel,Feng, Dong,et al. Lipids and their delta C-13 values reveal carbon assimilation and cycling in the methane-seep tubeworm Paraescarpia echinospica from the South China Sea[J]. DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS,2021,174:12.
APA	Guan, Hongxiang.,Birgel, Daniel.,Feng, Dong.,Peckmann, Joern.,Liu, Lei.,...&Tao, Jun.(2021).Lipids and their delta C-13 values reveal carbon assimilation and cycling in the methane-seep tubeworm Paraescarpia echinospica from the South China Sea.DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS,174,12.
MLA	Guan, Hongxiang,et al."Lipids and their delta C-13 values reveal carbon assimilation and cycling in the methane-seep tubeworm Paraescarpia echinospica from the South China Sea".DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS 174(2021):12.