去甲基甲基萘醌菌LLJ775的全基因组测序和比较基因组学分析  

Genome Sequencing and Comparative Genomics Analysis of Demequina sp.LLJ775

作　　者：孙凯 尹福 刘莉君 王双 张晓华[1,2,3] 于敏 Sun Kai;Yin Fu;Liu Lijun;Wang Shuang;Zhang Xiaohua;Yu Min(College of Marine Life Sciences,Ocean University of China,Qingdao 266003,China;Laboratory for Marine Ecology and Environmental Science,Laoshan Laboratory,Qingdao 266237,China;Institute of Evolution&Marine Biodiversity,Ocean University of China,Qingdao 266003,China)

机构地区：[1]中国海洋大学海洋生命学院,山东青岛266003 [2]崂山实验室海洋生态与环境科学功能实验室,山东青岛266237 [3]中国海洋大学海洋生物多样性与进化研究所,山东青岛266003

出　　处：《中国海洋大学学报(自然科学版)》2025年第5期70-86,共17页Periodical of Ocean University of China

基　　金：国家自然科学基金项目(41976137,92251303,U1706208)资助。

摘　　要：为了探究在冲绳海槽热液区中分离得到的一株新型去甲基甲基萘醌菌(Demequina sp.)LLJ775在海洋极端环境下的代谢机制与次级代谢产物合成能力,本研究对该菌株及同属参考菌株进行了比较基因组学分析。首先采用全基因组测序得到去甲基甲基萘醌菌LLJ775基因组完成图,通过系统发育学分析确定其进化地位,以对基因组进行功能注释分析与比较基因组学分析,从而探究该菌株的代谢特征和遗传潜力。去甲基甲基萘醌菌LLJ775基因组大小为2822402 bp,GC含量69.3%,共编码2738个基因。通过16S rRNA基因及单拷贝核心基因的系统发育分析发现,该菌株与同属菌株相似度较低(最高为98.41%),初步判断为该属的新种。功能注释分析发现,其复制、重组和修复相关基因占比高于同属菌株;乙醛酸支路代谢通路、亚硝酸盐还原途径和ABC型铁转运蛋白等编码基因的存在增强了该菌株对热液极端环境的适应性。此外,该菌株中还注释到碳酸酐酶、β-葡萄糖苷酶、异淀粉酶和透明质酸合酶等碳水化合物活性酶,以及番茄红素合成相关基因簇和其他次级代谢产物合成基因,说明该菌株具有极高的潜在应用价值。本研究通过全基因组测序及比较基因组学分析,揭示了新型去甲基甲基萘醌菌LLJ775的代谢潜力,为深入了解其对热液环境的适应机制提供了参考,也为发掘其应用前景提供了理论依据。To explore the metabolic mechanisms and secondary metabolite synthesis capacity of a novel strain Demequina sp.LLJ775 isolated from the hydrothermal vent of the Okinawa Trough in extreme marine environments,this study conducted a comparative genomics analysis of this strain and related reference strains.The genome of Demequina sp.LLJ775 was sequenced using whole genome sequencing.The evolutionary status of this strain was determined through phylogenetic analyses.Functional annotation and comparative genomics analyses of Demequina sp.LLJ775 and reference strains were performed to explore the metabolic characteristics and genetic potential of strains within this genus.The genome size of Demequina sp.LLJ775 was 2,822,402 bp,with the GC content of 69.3%and 2,738 protein-coding genes.Phylogenetic analyses of 16S rRNA genes and single-copy core genes revealed that this strain had low sequence similarities to its closely related strains,with the highest 16S rRNA gene sequence similarity being 98.41%.This preliminary result suggested that it was a novel species within the genus Demequina.Functional annotation analysis revealed that the proportion of genes related to replication,recombination,and repair in Demequina sp.LLJ775 was higher than in the reference strains.The presence of genes involved in metabolic pathways such as the glyoxylate shunt,nitrite reduction and encoding for ferric iron ABC-type transporter protein enhanced the adaptability of Demequina sp.LLJ775 to the extreme hydrothermal environment.Additionally,carbohydrate-active enzymes such as carbonic anhydrase,β-glucosidase,isoamylase and hyaluronan synthase were annotated in Demequina sp.LLJ775.Moreover,gene clusters related to lycopene synthesis and other secondary metabolite synthesis pathways were identified in Demequina sp.LLJ775,suggesting that this strain had significant application potential.The metabolic characteristics of the potential novel species Demequina sp.LLJ775 were revealed through whole genome sequencing and comparative genomics analysi

关 键 词：冲绳海槽 深海热液区 去甲基甲基萘醌菌LLJ775 全基因组测序 比较基因组学分析 

分 类 号：Q938.2[生物学—微生物学]