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根据螺旋霉素的生物合成途径对螺旋霉素产生菌产二素链霉菌进行推理选育，并获得了高产菌种。首先在紫外线诱变的基础上，筛选豆油耐性变株，得到菌株ＸＣ２－３７，其发酵效价较出发菌株ＸＣ１－２９提高９％。通过培养基优化，菌株ＸＣ２－３７的发酵效价提高６１．８％。再以紫外线处理菌株ＸＣ２－３７，并筛选缬氨酸诱导变株，得到菌株ＸＣ３－１１，其发酵效价较菌株ＸＣ２－３７提高２０％。菌株ＸＣ３－１１经自然分离得到菌株ＸＣ４－１８，发酵效价达到４５００ｕ／ｍｌ，为原始出发菌株ＸＣ１－２９的２．２５倍。传代试验表明菌株ＸＣ４－１８的高产遗传特性稳定。菌株ＸＣ４－１８应用于５０ｍ３发酵罐进行工业化生产，与原始出发菌株ＸＣ１－２９相比，发酵效价和发酵指数分别提高８４．９％和４３．６％。
Based on the biosynthetic pathway of spiramycin, Streptomyces sp. Producing Streptomyces sp. Was inoculated, and high-yielding strains were obtained. Based on the UV mutagenesis, the strain XC2-37 was screened for the tolerance of soybean oil, and its fermentation titer was 9% higher than that of the original strain XC1-29. Fermentation titer of strain XC2-37 increased by 61.8% through medium optimization. Strain XC2-37 was further treated with UV light and valine was selected to induce strain XC3-11. The fermentation titer was increased by 20% compared with that of strain XC2-37. Strain XC3-11 was isolated by natural strain XC4-18, fermentation titer reached 4500u / ml, 2.25 times the original starting strain XC1-29. Passage experiments showed that the high-yielding genetic characteristics of strain XC4-18 were stable. Strain XC4-18 was used in industrial production of 50m3 fermentor. Compared with the original strain XC1-29, the fermentation efficiency and fermentation index increased by 84.9% and 43.6%, respectively.