2-酮基-D-葡萄糖酸产生菌荧光假单胞菌K1005抗噬菌体菌株的选育

从２－酮基－Ｄ－葡萄糖酸产生菌荧光假单胞菌Ｋ１００５的异学发酵液中分离到两种噬菌体，分别将其命名为ＫＳ５０２和ＫＳ５０３。电镜观察表明ＫＳ５０２呈微球形，直径为６１ｎｍ；ＫＳ５０３呈蝌蚪形，具有直径为６８ｎｍ的六角形头部及８５ｎｍ长的尾部。利用紫外线诱变的方法，经多次分离筛选，获得了２株抗性稳定且产酸水平超过对照敏感菌的抗噬菌体菌株，可以应用于生产。

Selection of phage-resistant strains from 2-keto-D-gluconic acid producing strain

Two different phages named KS502 and KS503 were separated from the abnormal fermentation broth of Pseudomonas fluorescens K1005 strain which produced 2 keto D gluconic acid. The KS502 was micro sphere with a head of 61nm in diameter ,the KS503 phage was tadpole like with a hexagonal head of 68nm in diameter and a tail of 85nm long observed by electron microscope. Two hundred and eighteen resistant colonies against the phages were obtained by using U.V. light as a mutagen. After repeated separation and selection, two resistant strains against phages were finally obtained based on shaking flask fermentation result. The resistant strains gave a higher yield of 2 keto D gluconic acid than that of the original sensitive strain; the fermentation conversion rate of D glucose to 2 keto D gluconic acid reached over 90% and could be used in industrial fermentation process.