State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China.
State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China; Department of Pathogenic Biology, Binzhou Medical University, Yantai, 264003, PR China.
Environ Res. 2022 Jun;209:112888. doi: 10.1016/j.envres.2022.112888. Epub 2022 Feb 7.
Chloroflexi members are ubiquitous and have been extensively studied; however, the evolution and metabolic pathways of Chloroflexi members have long been debated. In the present study, the evolution and the metabolic potentials of 17 newly obtained Chloroflexi metagenome-assembled genomes (MAGs) were evaluated using genome and horizontal gene transfer (HGT) analysis. Taxonomic analysis suggests that the MAGs of the present study might be novel. One MAG encodes genes for anoxygenic phototrophy. The HGT analysis suggest that genes responsible for anoxygenic phototrophy in the MAG might have been transferred from Proteobacteria/Chlorobi. The evolution of anaerobic photosynthesis, which has long been questioned, has now been shown to be the result of HGT events. An incomplete Wood-Ljungdahl pathway (with missing genes metF, acsE, fdh, and acsA) was reported in Dehalococcoidetes members. In the present study, MAGs that were not the Dehalococcoidetes members encode genes acsA, acsB, metF and acsE. The genes responsible for sulfate reduction (sat, cysC and sir), dissimilatory sulfite reductase (dsrA and dsrB), and aerobic and anaerobic carbon monoxide oxidation (coxSML and cooSF) were detected in the present study MAGs. The present study expands our knowledge of the possible metabolic potentials of the phylum Chloroflexi and clarifies the evolution of anaerobic photosynthesis.
绿弯菌门成员无处不在，并且已经得到了广泛的研究；然而，绿弯菌门成员的进化和代谢途径长期以来一直存在争议。在本研究中，通过基因组和水平基因转移（HGT）分析评估了 17 个新获得的绿弯菌门宏基因组组装基因组（MAG）的进化和代谢潜力。分类分析表明，本研究的 MAG 可能是新的。一个 MAG 编码了进行厌氧光合作用的基因。HGT 分析表明，MAG 中负责厌氧光合作用的基因可能是从变形菌门/绿菌门转移而来的。长期以来一直存在争议的厌氧光合作用的进化，现在已经被证明是 HGT 事件的结果。曾报道脱硫菌门成员中存在不完整的 Wood-Ljungdahl 途径（缺少 metF、acsE、fdh 和 acsA 基因）。在本研究中，不属于脱硫菌门成员的 MAG 编码了 acsA、acsB、metF 和 acsE 基因。本研究还检测到了硫酸盐还原（sat、cysC 和 sir）、异化亚硫酸盐还原酶（dsrA 和 dsrB）以及好氧和厌氧一氧化碳氧化（coxSML 和 cooSF）的基因。本研究扩展了我们对绿弯菌门可能的代谢潜力的认识，并阐明了厌氧光合作用的进化。
