1株产灵菌红素家族红色色素细菌的分离鉴定及其色素性质研究

The identification of prodigiosin family red pigment producing bacterium and characterization of the red pigment

对分离自重庆酉阳喀斯特槽谷石漠化地区土壤的1株产红色色素的细菌进行了形态学、生理生化特性和16S rRNA序列鉴定,进一步对该色素的溶解性、抑菌性和稳定性行进了研究,测定了其最大紫外吸收波长;同时,采用硅胶色谱柱对色素进行了纯化,通过薄层层析、质谱和光谱扫描对色素成分进行分析。结果显示,该菌在30℃培养时,色素产量较高。该色素在无水乙醇中的溶解性优于其他有机溶剂,在530 nm处有最大紫外吸收峰;该红色素对大肠杆菌(Escherichia coli)及耻垢分枝杆菌(Mycobacterium smegmatis)无抑菌作用;对极端pH值较敏感,尤其是强碱性pH值。且其光和热稳定性良好,耐氧化能力较强,耐还原能力较弱;金属离子对该色素有不同程度的消色作用,Cu^(2+)的消色作用最明显。16S rRNA序列分析结果显示,该菌与多株黏质沙雷氏菌(Serratia marcescens)的16S rRNA序列一致。质谱分析结果显示,该色素的分子质量为324.2,与灵菌红素的分子质量非常接近,但光谱扫描结果与其不一致。

Natural pigments are frequently used in food and dye industry. A bacterium producing red pigment was isolated from the Karst soil of Chongqing. The red pigment was characterized. The bacterium was identified as Serratia marcescens by 16S rRNA sequencing. The optimum temperature for the bacterium to yield maximum pigment was 30 ℃. The maximum absorption peak of the pigment was at 530 nm. The pigment could be dissolved in different reagents, while the optimal extraction reagent was ethanol. It was quite stable over temperature, light and antioxidant, while unstable under reducing agent or alkaline condition. Cu2＋ could deeolorize the pigment. The purified pigment did not show inhibitory effect upon Escherichia coli or Mycobacterium smegmatis. The mass spectrum of this pigment was similar to that of prodigiosin.