DOI: 10.1111/gbi.12129
Scopus记录号: 2-s2.0-84927113436
论文题名: Phylogenetic analysis of HpnP reveals the origin of 2-methylhopanoid production in Alphaproteobacteria
作者: Ricci J.N. ; Michel A.J. ; Newman D.K.
刊名: Geobiology
ISSN: 1472-4677
EISSN: 1472-4669
出版年: 2015
卷: 13, 期: 3 起始页码: 267
结束页码: 277
语种: 英语
Scopus关键词: bacterium
; catagenesis
; evolutionary biology
; photosynthesis
; phylogenetics
; steroid
; Alphaproteobacteria
; Bacteria (microorganisms)
; Cyanobacteria
; 2-methylhopane
; triterpene
; Alphaproteobacteria
; cyanobacterium
; evolution
; genetics
; metabolism
; photosynthesis
; phylogeny
; Alphaproteobacteria
; Biological Evolution
; Cyanobacteria
; Photosynthesis
; Phylogeny
; Triterpenes
Scopus学科分类: Earth and Planetary Sciences: General Earth and Planetary Sciences
; Environmental Science: General Environmental Science
; Agricultural and Biological Sciences: Ecology, Evolution, Behavior and Systematic
英文摘要: Hopanoids are bacterial steroid-like lipids that can be preserved in the rock record on billion-year timescales. 2-Methylhopanoids are of particular interest to geobiologists because methylation is one of the few chemical modifications that remain after diagenesis and catagenesis. 2-Methylhopanes, the molecular fossils of 2-methylhopanoids, are episodically enriched in the rock record, but we do not have a robust interpretation for their abundance patterns. Here, we exploit the evolutionary record found in molecular sequences from extant organisms to reconstruct the biosynthetic history of 2-methylhopanoids using the C-2 hopanoid methylase, HpnP. Based on HpnP phylogenetic analysis, we find that 2-methylhopanoids originated in a subset of the Alphaproteobacteria. This conclusion is statistically robust and reproducible in multiple trials varying the outgroup, trimming stringency, and ingroup dataset used to infer the evolution of this protein family. The capacity for 2-methylhopanoid production was likely horizontally transferred from the Alphaproteobacteria into the Cyanobacteria after the Cyanobacteria's major divergences. Together, these results suggest that the ancestral function of 2-methylhopanoids was not related to oxygenic photosynthesis but instead to a trait already present in the Alphaproteobacteria. Moreover, given that early 2-methylhopane deposits could have been made solely by Alphaproteobacteria before the acquisition of hpnP by Cyanobacteria, and that the Alphaproteobacteria are thought to be ancestrally aerobic, we infer that 2-methylhopanoids likely arose after the oxygenation of the atmosphere. This finding is consistent with the geologic record-the oldest syngenetic 2-methylhopanes occur after the rise of oxygen, in middle Proterozoic strata of the Barney Creek Formation. © 2015 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/85156
Appears in Collections: 影响、适应和脆弱性
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作者单位: Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States; Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United States; Howard Hughes Medical Institute, Pasadena, CA, United States
Recommended Citation:
Ricci J.N.,Michel A.J.,Newman D.K.. Phylogenetic analysis of HpnP reveals the origin of 2-methylhopanoid production in Alphaproteobacteria[J]. Geobiology,2015-01-01,13(3)