22种丝状异型胞固氮蓝细菌的16S rDNA的PCR-RFLP分析

Analysis of 22 Strains of Nitrogen-fixing Filamentous Cyanobacteria with Heterocyst by Using PCR-RFLP of 16S rDNA

用 1对引物CYA10 6F及 781R(a)从 2 3种蓝细菌的DNA中扩增出一条 6 0 0bp的 16SrDNA PCR片段 .对该片段进行的限制性酶切长度多态性 (RFLP)分析表明 :可将其中 2 1种自生或共生的丝状异型胞固氮蓝细菌的样品分为 2个类群组 ,基本上对应于形态分类上的Anabaena及Nostoc属 .但有 1种被认为是Anabaena的蓝细菌以及作为对照的 1种聚球藻 (Synechococcus)蓝细菌样品被明显区分出来 ,并发现Anabaena属的蓝细菌也可同被子植物根乃拉草 (Gunnera)

A 16S rDNA-PCR fragment at about 600 bp was amplified from 23 cyanobacterial accessions by using primer pair CYA106F and 781R(a). The RFLP analysis of this fragment indicated that of these tested accessions, 21 strains of nitrogen-fixing filamentous cyanobacteria with heterocyst were separated into two clusters basically corresponding to Anabeana and Nostoc genus on the basis of morphological classification. but 1 strain identified as Anabeana and 1 strain of Synechococcus as check showed a greatly difference from the two clusters. The result also revealed that the Anabeana strain possibly formed symbiosis with angiosperm Gunnera for nitrogen fixation.