摘要
采用电镜及荧光显微镜方法,对经60Coγ诱变筛选获得的绿色产色链霉菌(Streptomyces viridochromogenes)阿维拉霉素高产突变株H15的菌落、孢子丝、分生孢子分化特征进行了研究。与原始菌株4.1119不同的是,突变株H15形态呈现显著变异:灰白绿色菌落,直线型孢子丝,分生孢子表面光滑无刺突,而菌株4.1119为螺旋状孢子丝,孢子表面带刺。液体培养菌丝荧光染色结果表明,H15菌株在液体培养条件下菌丝团形态分化过程也发生显著改变,孢子萌发形成多隔室菌丝,放射状生长逐渐形成菌丝团,核心菌丝出现凋亡后,菌丝团直径增长停滞。与原始菌株相比,突变株H15菌丝的成簇、形成完整菌丝团需要较长时间(48h才形成完整菌丝团,245μm),菌丝团直径增长停滞阶段及凋亡的延滞使得产物阿维拉霉素得以较好积累,阿维拉霉素的合成主要集中在此阶段。此后菌丝生物量虽维持小幅波动,但对阿维拉霉素的积累没有意义。因此推测菌丝团的形成历程、停滞阶段菌丝团直径增长及凋亡"相对平衡"对于阿维拉霉素的积累可能有重要意义。
Morphological differentiation characters such as colony,sporotrichial,and conidiophores of mutant H15,which was derived from Streptomyces viridochromogenes 4.1119 treated with 60Co γ-rays irradiation,were investigated by scanning electron microscope and fluorescence microscope.The results showed that mutant H15 was remarkable variation from the strain 4.1119.Cultured on agar surface,H15 had a grayish-whitish-green colony,linear sporotrichial,smooth and round conidiophore without any spike,whereas strain 4.1119 had spiral sporotrichial and round conidiophore with spike on the surface.In the submerged cultures,differentiation process of mycelia pellet of H15 was also different.Spores germinated as a compartmentalized mycelium,the young compartmentalized mycelium started to form pellets which grew in a radial pattern.After apoptosis took place in the center of the pellets,the pellet diameter growth arrested.Compared with the strain 4.1119,H15 required a long developing course for hyphae clustering and pellets formation（at 48h,245μm）.The stage of pellet arrest or apoptosis in the pellet centre were extended,which would benefit the avilamycin accumulation since the antibiotic was mainly produced at the same time.These suggested that pellet formation kinetics,relational balance between pellet diameter enlargement and mycelia apoptosis in the pellet arrest stage were key factors to avilamyin accumulation in submerged cultures of Streptomyces viridoehrongenes H15.
出处
《核农学报》
CAS
CSCD
北大核心
2010年第4期689-693,747,共6页
Journal of Nuclear Agricultural Sciences
基金
浙江省科技厅专项(2008C22SA760007)
关键词
绿色产色链霉菌
阿维拉霉素
形态分化
荧光染色
Streptomyces viridochromogenes
avilamycin
morphological differentiation
fluorescence staining
