PHENOTYPIC FEATURES AND GENETIC DIVERSITY OF STRAINS OF RHODOPSEUDOMONAS
几株红假单胞菌属细菌的表观特征及其遗传多样性研究

14 strains of purple non-sulfur bacteria and 3 type strains of Rhodopseudornonas were investigated by phenotypic characterizing, DNA-DNA hybridizing and DGGE analyzing. The characteristics of their morphology, structure and physiology show that 14 strains of isolates have the features of the genus Rhodopseudomonas dividing asymmetrically by budding, lamellar intracytoplasmic membranes, presence of bacteriochlorophyll a and carotenoids of the normal spirilloxanthin series. On the base of their differences in morphology, growth, corbon sources 14 strains can be divided into 2 groups g-c group, T group.Parts of 16S rRNA gene were amplified by using a pair of primers 341f-906r. Denaturing gradient gel electrophoresis(DGGE) of PCR-amplified fragment of rDNA indicated that they have 3 genetic types 1 of them, including 6 of 8 strains of T groups is similar to that of Rps. rutila Ri, the other 2 types, represented seperately by 2 of T group or all the g-c group, were different from that of either of 3 type strains The Data of the DNA-DNA hybridization of 8 representative strains indicated that the differences between different types were enought to separate them into different species including 2 possible new species.