气候变化领域集成服务门户(CCPortal): GDGT cyclization proteins identify the dominant archaeal sources of tetraether lipids in the ocean

CCPortal

DOI	10.1073/pnas.1909306116
	GDGT cyclization proteins identify the dominant archaeal sources of tetraether lipids in the ocean
	Zeng Z.; Liu X.-L.; Farley K.R.; Wei J.H.; Metcalf W.W.; Summons R.E.; Welander P.V.
发表日期	2019
ISSN	0027-8424
起始页码	22505
结束页码	22511
卷号	116 期号:45
英文摘要	Glycerol dibiphytanyl glycerol tetraethers (GDGTs) are distinctive archaeal membrane-spanning lipids with up to eight cyclopentane rings and/or one cyclohexane ring. The number of rings added to the GDGT core structure can vary as a function of environmental conditions, such as changes in growth temperature. This physiological response enables cyclic GDGTs preserved in sediments to be employed as proxies for reconstructing past global and regional temperatures and to provide fundamental insights into ancient climate variability. Yet, confidence in GDGT-based paleotemperature proxies is hindered by uncertainty concerning the archaeal communities contributing to GDGT pools in modern environments and ambiguity in the environmental and physiological factors that affect GDGT cyclization in extant archaea. To properly constrain these uncertainties, a comprehensive understanding of GDGT biosynthesis is required. Here, we identify 2 GDGT ring synthases, GrsA and GrsB, essential for GDGT ring formation in Sulfolobus acidocaldarius. Both proteins are radical S-adenosylmethionine proteins, indicating that GDGT cyclization occurs through a free radical mechanism. In addition, we demonstrate that GrsA introduces rings specifically at the C-7 position of the core GDGT lipid, while GrsB cyclizes at the C-3 position, suggesting that cyclization patterns are differentially controlled by 2 separate enzymes and potentially influenced by distinct environmental factors. Finally, phylogenetic analyses of the Grs proteins reveal that marine Thaumarchaeota, and not Euryarchaeota, are the dominant source of cyclized GDGTs in open ocean settings, addressing a major source of uncertainty in GDGT-based paleotemperature proxy applications. © 2019 National Academy of Sciences. All rights reserved.
英文关键词	GDGT; Paleotemperature proxies; Radical SAM; Sulfolobus
语种	英语
scopus关键词	cyclopentane; glycerol dibiphytanyl glycerol tetraether derivative; GrsA protein; GrsB protein; membrane lipid; s adenosylmethionine; synthetase; unclassified drug; archaeon; Article; biochemical analysis; bioinformatics; comparative genomic hybridization; controlled study; cyclization; environmental factor; environmental temperature; Euryarchaeota; gene deletion; lipid analysis; nonhuman; ocean environment; phylogeny; priority journal; protein depletion; protein synthesis; sequence homology; Sulfolobus acidocaldarius; Thaumarchaeota; thermoacidophilic archaeon
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160335
作者单位	Zeng, Z., Department of Earth System Science, Stanford University, Stanford, CA 94305, United States; Liu, X.-L., Department of Geosciences, University of Oklahoma, Norman, OK 73019, United States; Farley, K.R., Department of Microbiology, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States; Wei, J.H., Department of Earth System Science, Stanford University, Stanford, CA 94305, United States; Metcalf, W.W., Department of Microbiology, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States, Institute for Genomic Biology, University of Illinois Urbana–Champaign, Urbana, IL 61801, United States; Summons, R.E., Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Welander, P.V., Department of Earth System Science, Stanford University, Stanford, CA 94305, United States
推荐引用方式 GB/T 7714	Zeng Z.,Liu X.-L.,Farley K.R.,et al. GDGT cyclization proteins identify the dominant archaeal sources of tetraether lipids in the ocean[J],2019,116(45).
APA	Zeng Z..,Liu X.-L..,Farley K.R..,Wei J.H..,Metcalf W.W..,...&Welander P.V..(2019).GDGT cyclization proteins identify the dominant archaeal sources of tetraether lipids in the ocean.Proceedings of the National Academy of Sciences of the United States of America,116(45).
MLA	Zeng Z.,et al."GDGT cyclization proteins identify the dominant archaeal sources of tetraether lipids in the ocean".Proceedings of the National Academy of Sciences of the United States of America 116.45(2019).