一株产紫色素放线菌的鉴定及其色素特性研究

Identification and Characterization of Purple Pigment-producing Actinomycete Strain

从河南碱性土壤样品中筛选到一株命名为LK-178的放线菌菌株,在高氏合成培养基上其气生菌丝灰白,产可溶性紫色素.镜检观察孢子链长直、孢子圆柱形,通过形态、生理生化特征初步确定为链霉菌.16SrRNA序列分析显示,该菌基因序列与比基尼链霉菌(Streptomyces bikiniensis)AB208713基因序列有99.0%的最高相似性.用Neighbor-joining(NJ)等构建系统发育树,并用Bootstraping法对其评价,将菌株LK-178归属于比基尼链霉菌(S.bikiniensis).抑菌试验表明,该菌具有抗革兰氏阳性、革兰氏阴性细菌和真菌活性.用紫外可见分光光度计和化学分析确定该色素性质稳定,产量较高,总色价相对单位较高,达到147U/mL,产量达到13.4g/L.

An actinomycete, named strain LK-178, was isolated from an alkaline soil sample in Henan, China. It produced grayish-white aerial mycelium and purple diffusible pigment on Gause＇s synthetic agar. Microscopic observation revealed that it produced straight chain of cylindrical spores. It was primarily identified as genus Streptomyces according to its morphological, physiological and biochemical characteristics. The 16S rRNA gene sequence of strain LK-178 shared the highest similarity （99.0%） with that of S. bikiniensis AB208713. The phylogenetic tree of strain LK-178 was derived with NJ and analyzed with bootstraping. The result demonstrated that it belonged to S. bikiniensis. The test on antimicrobial activities showed that it had ability against the Gram-positive, Gram-negative bacteria and fungi. The UV- VIS spectrometry and chemical analysis revealed that the pigment producted by this strain was stable, total relative color value of the pigment was as high as 147 U/mL and total pigment yield reached 13.4 g/L. Fig 3, Tab 3, Ref 18