气候变化领域集成服务门户(CCPortal): Potential Rhodopsin- and Bacteriochlorophyll-Based Dual Phototrophy in a High Arctic Glacier

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DOI	10.1128/mBio.02641-20
	Potential Rhodopsin- and Bacteriochlorophyll-Based Dual Phototrophy in a High Arctic Glacier
	Zeng, Yonghui; Chen, Xihan; Madsen, Anne Mette; Zervas, Athanasios; Nielsen, Tue Kjaergaard; Andrei, Adrian-Stefan; Lund-Hansen, Lars Chresten; Liu, Yongqin; Hansen, Lars Hestbjerg
通讯作者	Zeng, YH (通讯作者)
发表日期	2020
ISSN	2150-7511
卷号	11 期号:6
英文摘要	Conserving additional energy from sunlight through bacteriochlorophyll (BChl)-based reaction center or proton-pumping rhodopsin is a highly successful life strategy in environmental bacteria. BChl and rhodopsin-based systems display contrasting characteristics in the size of coding operon, cost of biosynthesis, ease of expression control, and efficiency of energy production. This raises an intriguing question of whether a single bacterium has evolved the ability to perform these two types of phototrophy complementarily according to energy needs and environmental conditions. Here, we report four Tardiphaga sp. strains (Alphaproteobacteria) of monophyletic origin isolated from a high Arctic glacier in northeast Greenland (81.566 degrees N, 16.363 degrees W) that are at different evolutionary stages concerning phototrophy. Their >99.8% identical genomes contain footprints of horizontal operon transfer (HOT) of the complete gene clusters encoding BChl- and xanthorhodopsin (XR)-based dual phototrophy. Two strains possess only a complete XR operon, while the other two strains have both a photosynthesis gene cluster and an XR operon in their genomes. All XR operons are heavily surrounded by mobile genetic elements and are located close to a tRNA gene, strongly signaling that a HOT event of the XR operon has occurred recently. Mining public genome databases and our high Arctic glacial and soil metagenomes revealed that phylogenetically diverse bacteria have the metabolic potential of performing BChl- and rhodopsin-based dual phototrophy. Our data provide new insights on how bacteria cope with the harsh and energy-deficient environment in surface glacier, possibly by maximizing the capability of exploiting solar energy. IMPORTANCE Over the course of evolution for billions of years, bacteria that are capable of light-driven energy production have occupied every corner of surface Earth where sunlight can reach. Only two general biological systems have evolved in bacteria to be capable of net energy conservation via light harvesting: one is based on the pigment of (bacterio-)chlorophyll and the other is based on proton-pumping rhodopsin. There is emerging genomic evidence that these two rather different systems can coexist in a single bacterium to take advantage of their contrasting characteristics in the number of genes involved, biosynthesis cost, ease of expression control, and efficiency of energy production and thus enhance the capability of exploiting solar energy. Our data provide the first clear-cut evidence that such dual phototrophy potentially exists in glacial bacteria. Further public genome mining suggests this understudied dual phototrophic mechanism is possibly more common than our data alone suggested.
关键词	SEA-ICE BACTERIAL
英文关键词	phototrophy; glacial bacteria; bacteriochlorophyll; rhodopsin; genome evolution
语种	英语
WOS研究方向	Microbiology
WOS类目	Microbiology
WOS记录号	WOS:000641045400045
来源期刊	MBIO
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/260063
推荐引用方式 GB/T 7714	Zeng, Yonghui,Chen, Xihan,Madsen, Anne Mette,et al. Potential Rhodopsin- and Bacteriochlorophyll-Based Dual Phototrophy in a High Arctic Glacier[J]. 中国科学院青藏高原研究所,2020,11(6).
APA	Zeng, Yonghui.,Chen, Xihan.,Madsen, Anne Mette.,Zervas, Athanasios.,Nielsen, Tue Kjaergaard.,...&Hansen, Lars Hestbjerg.(2020).Potential Rhodopsin- and Bacteriochlorophyll-Based Dual Phototrophy in a High Arctic Glacier.MBIO,11(6).
MLA	Zeng, Yonghui,et al."Potential Rhodopsin- and Bacteriochlorophyll-Based Dual Phototrophy in a High Arctic Glacier".MBIO 11.6(2020).