几株光合细菌的表型特征及DNA－NDA同源性分析

对５株新分离的光合细菌从形态、生理生化及ＤＮＡ－ＤＮＡ同源性等方面进行了研究．结果表明，菌株８与深红红螺菌（Ｐｈｏｄｏｓｐｉｒｉｌｌｕｍｒｕｂｒｕｍ）的模式菌株ＡＴＣＣ１１１７０的ＤＮＡ－ＤＮＡ同源性为９７％，菌株３７与沼泽红假单胞菌（Ｒｈｏｄｏｐｓｅｕｄｏｍｏｎａｓｐａｌｕｓｔｒｉｓ）的模式菌株ＡＴＣＣ１７００１的ＤＮＡ－ＤＮＡ同源性为８０％；菌株５５与球形红杆菌（Ｒｈｏｄｏｂａｃｔｅｒｓｐｈａｅｒｏｉｄｅｓ）的模式菌株ＡＴＣＣ１７０２３的ＤＮＡ－ＤＮＡ同源性为７１％；菌株４０和５２分别为另外两个ＤＮＡ同源群．根据各菌株形态、生理生化等表型特征以及ＤＮＡＧ＋Ｃｍｏｌ％和ＤＮＡ－ＤＮＡ同源性分析结果，确定了几株光合细菌的分类地位．

PHENOTYPIC FEATURES AND DNA-DNA HOMOLOGY ANALYSES OF SOME PHOTOSYNTHETIC BACTERIA

The phenotypic features and DNA-DNA hybridization of five isolatsd PSB strains were studied. The results of DNA-DNA homdogy analyses indicated that strain 8 and Rhodospiricllum rubrum ATCC 11 170 contained a DNA-DNA homology group,and they showed a high level of relateness and their DNA-DNA homology was 97% ; the homolosy of DNA-DNA between strain 37 and Rhodopseudomonas palustris ATCC 17 001was 80% ; the homology of DNA-DNA between strain 55 and Rhodobacter sphaeroides ATCC 17 023 was 71 % ; strains 40 and 52 formed other two distinct homology groups. On the besis of phenotypic features,the DNA base composition and DNA-DNA hybridization were used to determine the taxonomic positions of some PSB strains.