核糖体工程改造海绵共附生放线菌紫色素的特性

Characterization of Purple Pigment Produced by Sponge Associated Actinomycete Strain Transformed by Ribosome Engineering

从西沙海域未鉴定海绵样品中分离到一株命名为SCKA-96.5的放线菌菌株,该菌在海水高氏I号培养基上产生灰白色气生菌丝。16 S rDNA序列分析表明,该菌为链霉菌属放线菌。通过核糖体工程技术获得其变异菌株SCKA-96.5K,该变异株在海水高氏I号培养基上能稳定地产生可溶性紫色素。对SC-KA-96.5K所产的紫色素进行粗提取及稳定性分析,了解相关理化因素对其稳定性的影响。初步研究结果表明,在波长600 nm处该紫色素具有最大吸光度;热稳定性较好;颜色随pH的变化明显;强氧化剂次氯酸钠对其破坏较大,在弱还原剂中比较稳定;葡萄糖等食品添加剂对其基本没有影响。作为一种潜在的天然色素资源,该紫色素具有一定的工业开发价值。

An actinomycete strain SCKA-96.5 was isolated from an unidentified sponge sample from Xisha sea.The strain produced grayish-white aerial mycelium on Guase’s No.I medium supplemented with seawater.The 16 S rRNA gene sequence of strain SCKA-96.5 showed that it was assigned to Streptomyces.Its mutant strain,SCKA-96.5K,obtained by ribosome engineering,was able to produce a purple diffusible pigment stably.The pigment was extracted;and its physicochemical properties were analyzed.The results showed that the maximum absorption wavelength was 600 nm;the pigment was stable to heat and food additives;its color changed significantly when pH changed;strong oxidant NaClO could destroy the pigment while weak reductants didn’t had any effect on the pigment.The purple pigment had the potential to be developed for future application as a kind of natural pigment.