Wang Shuo, Mu Dashuai, Du Zong-Jun
Marine College, Shandong University, Weihai, China.
State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.
Front Microbiol. 2020 Apr 22;11:698. doi: 10.3389/fmicb.2020.00698. eCollection 2020.
A novel bacterial strain, designated YN101, was isolated from a marine solar saltern in the coast of Weihai, Shandong Province, China. Strain YN101 was Gram-stain negative, facultatively anaerobic, oxidase and catalase negative bacterium with the ability to prey on other microbes. A cross-streaking culture method was utilized to analyze the predatory activity of strain YN101. The results showed strain YN101 could prey on various bacteria, either Gram-stain negative or Gram-stain positive. According to the predatory assays, different species in the same genus may behave differently when attacked by strain YN101. The predatory behavior of strain YN101 to four typical species was analyzed, and furthermore, predation to am2 were quantitatively studied by fluorogenic quantitative PCR, and the gene copies decreased over two magnitudes. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YN101 shared the greatest sequence similarity of 93.9% to FA350. The complete genome sequence of strain YN101 was 8,047,306 bp in size and the genomic DNA G + C content was 63.8 mol%. The digital DNA-DNA hybridization (dDDH) values and average nucleotide identity (ANI) values between strain YN101 and FA350 were 13.9 and 74.0%. The genetic features showed that the biosynthesis of many important compounds was deficient in genome of strain YN101, which may lead to its predation. Moreover, its genome encoded many genes affiliated with type IV pili, secretion system, membrane proteins and transduction proteins. Similar with myxobacteria and and like organisms (BALOs), these genes should play important roles in motility, adhesion or virulence to attack prey cells during predation. The predominant polar lipid profile of strain YN101 consisted of phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), and one unidentified aminophospholipid (APL). The major cellular fatty acid of strain YN101 was iso-C, and the sole respiratory quinone was MK-7. Based on the chemotaxonomic, physiological and biochemical characteristics, strain YN101 represents a novel species of a novel genus in the family , for which the name gen. nov., sp. nov. is proposed. The type strain is YN101 (=KCTC 72083 = MCCC 1H00374).
从中国山东省威海市海岸的一个海洋太阳能盐场中分离出一株新型细菌菌株，命名为YN101。菌株YN101为革兰氏染色阴性、兼性厌氧、氧化酶和过氧化氢酶阴性的细菌，具有捕食其他微生物的能力。采用交叉划线培养法分析菌株YN101的捕食活性。结果表明，菌株YN101可以捕食各种革兰氏阴性或革兰氏阳性细菌。根据捕食试验，同一属中的不同物种在受到菌株YN101攻击时可能表现不同。分析了菌株YN101对四种典型物种的捕食行为，此外，通过荧光定量PCR对其捕食am2进行了定量研究，基因拷贝数下降了两个数量级以上。基于16S rRNA基因序列的系统发育分析表明，菌株YN101与FA350的序列相似性最高，为93.9%。菌株YN101的完整基因组序列大小为8,047,306 bp，基因组DNA的G + C含量为63.8 mol%。菌株YN101与FA350之间的数字DNA-DNA杂交（dDDH）值和平均核苷酸同一性（ANI）值分别为13.9和74.0%。遗传特征表明，菌株YN101的基因组中许多重要化合物的生物合成存在缺陷，这可能导致其捕食行为。此外，其基因组编码了许多与IV型菌毛、分泌系统、膜蛋白和转导蛋白相关的基因。与粘细菌和类粘细菌（BALOs）相似，这些基因在捕食过程中对猎物细胞的运动、粘附或毒性方面应发挥重要作用。菌株YN101的主要极性脂质谱由磷脂酰乙醇胺（PE）、磷脂酰甘油（PG）、二磷脂酰甘油（DPG）和一种未鉴定的氨基磷脂（APL）组成。菌株YN101的主要细胞脂肪酸为异-C，唯一的呼吸醌为MK-7。基于化学分类、生理和生化特征，菌株YN101代表了一个新属中的一个新物种，为此提出新属名 gen. nov.，新种名 sp. nov.。模式菌株为YN101（=KCTC 72083 = MCCC 1H00374）。
