阿维菌素产生菌的定向育种与突变株代谢产物的研究

【作者】 王晓伟；

【导师】 白秀峰；

【作者基本信息】 沈阳药科大学 ， 微生物药学， 2001， 硕士

【摘要】 本文以阿维菌素链霉菌为研究对象。 以菌株C514为试验菌株研究了影响阿维菌素C₅位氧甲基化程度的因素。试验结果表明：菌体内S-腺苷甲硫氨酸（SAM）的浓度可以调控阿维菌素的C₅位氧甲基化程度。当菌体内SAM的含量升高时，可以增加阿维菌素A组分的比例，而减少菌体内SAM的含量可以使B组分的比例升高。 以亚硝基胍为诱变剂对出发菌株#7进行了选育。采用磺胺敏感、甲硫氨酸诱导筛选模型，获得了B组分含量达到82％的菌株M-2，其B组分含量较出发菌株提高了40％左右。以耐受氯化艳为筛选模型结合原生质体再生及诱变获得了总效价达到5600μg/ml以上的高产菌株Pr27，其中B_1a效价在2300μg/ml以上。 在菌种选育过程中，获得了两株突变菌株E107和#21。它们所产生的主要代谢产物E107a、21-A、21-B被鉴定为寡霉素A、阿维菌素糖苷配基A_2a、阿维菌素糖苷配基A_1a。两个次要代谢产物E107b、21-C可能为寡霉素C及阿维菌素糖苷配基B_1a。更多还原

【Abstract】 ABSTRACTIn this paper, Streptomyces avermitlis was used as experimental object.Using strain C514 as experimental strain, the factors that influenced C5-O methylation of avermectins were studied. The experimental results showed that the C5-O methylation of avermectins was regulated by the concentration of 5adenosylmethionine(SAM). The A components of avermectins increased when the concentration of SAM was high and the B components of avermectins increased when the concentration of SAM decreased.In the course of screening for high producing strains and high B components producing strains, strain #7, the original strain, was treated by NTG. By selecting strains that were sensitive to sulfanilamide and strains that were induced by methionine, a strain, M-2, which produced about 82% B components was obtained. The strain Pr27 that has a high avermectins producing capacity was obtained by the method of protoplast regeneration combined with the model of chlorocaeaium tolerance.In the course of strain screening, two mutational strains, El07 and #21, were obtained. The main metabolites they produced, ElO7a, 21-A and 21-B, were identified as Oligomycin A, Avermectin aglycone A2a and Avermectin aglycone Aia. The possible structures of two minor components, E107b and 21-C, was proposed.更多还原