基金项目:自治区重点研发计划(2016B03041-2); 新疆维吾尔自治区自然科学基金(2015211A038); 新疆干旱区植物逆境重点实验室项目(XJNUSYS112018A01)
通信作者:xugela@163.com
采用多相分类学的方法,即通过表型、化学分类和分子分类特征,并综合系统发育分析结果,探究我国新疆库尔勒地区黑果枸杞(Lycium ruthenicum)根际土样来源菌株438HGGQ3-1T的分类学地位.结果显示:菌株438HGGQ3-1T为革兰氏染色阳性,可形成广泛分枝状营养菌丝、略带弯曲的丝状气生菌丝和末端平截的杆状分生孢子,最适生长条件为28~37 ℃、pH 7.0~7.5和2%~12%(质量分数)NaCl.该菌株的氧化酶活性呈阴性,过氧化氩酶活性呈阳性,以内消旋2,6-二氨基庚二酸作为特征性二氨基酸,以葡萄糖和核糖作为特征性全细胞糖,细胞磷脂包含磷脂酰乙醇胺、二磷脂酰甘油、磷脂酰甘油、磷脂酰肌醇甘露糖苷、磷脂酰肌醇和2种含糖的磷脂,主要的甲基萘醌为MK-10(H4)、MK-9(H4)和MK-10(H2),主要脂肪酸为anteiso-C17:0、anteiso-C15:0和iso-C16:0.菌株438HGGQ3-1T与糖霉菌科Salininema proteolyticum Miq-4T、Paraglycomyces xinjiangensis TRM 49201T和Salilacibacter albus J11Y309T同源性较高,对应的16S rRNA基因序列相似度分别为99.79%,99.67%和96.00%,与S.proteolyticum IBRC-M 10908T和P.xinjiangensis CCTCC AA 2013002T的DNA-DNA杂交值均高于70%.综上分析表明菌株438HGGQ3-1T为S.proteolyticum.
A halophilic actinobacterium,designated as strain 438HGGQ3-1T,was isolated from a rhizosphere soil sample of the medicinal plant Lycium ruthenicum.In the present work,the taxonomic position of strain 438HGGQ3-1T was elucidated.Phenotypic,chemotaxonomic characterizations and genotypic and phylogenetic analyses were performed in this study.The results showed that cells of strain 438HGGQ3-1T were Gram-positive,and formed extensive branched substrate mycelium,slightly twisted aerial mycelia and chains of square-ended conidia.Cells grew optimally at temperature of 28 ℃ to 37 ℃,pH of 7.0 to 7.5 and in the presence of 2% to 12%(by mass)NaCl.The isolate was negative for oxidase activity and positive for catalase activity.It contained 2,6-diaminopimelic acid as the diagnostic diamino acid and glucose and ribose as the whole-cell sugars.The phospholipids consisted of phosphatidylethanolamine,diphosphatidylglycerol,phosphatidylglycerol,phosphatidylinositol mannoside,phosphatidylinositol and two phosphoglycolipids.The major menaquinones were MK-10(H4),MK-9(H4)and MK-10(H2).The major fatty acids were anteiso-C17:0,anteiso-C15:0 and iso-C16:0.It shared the highest levels of 16S rRNA gene sequence similarity with Salininema proteolyticum Miq-4T(99.79%),Paraglycomyces xinjiangensis TRM 49201T(99.67%)and Salilacibacter albus J11Y309T(96.00%).The levels of DNA-DNA relatedness with S.proteolyticum IBRC-M 10908T and P.xinjiangensis CCTCC AA 2013002T were both above 70%.In summary,the strain 438HGGQ3-1T was identified as a strain of the species S.proteolyticum.