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用透射电镜首次观察到杨梅根瘤内生菌泡囊结构存在两种类型,有隔或无隔,椭圆形,直径1.3～3.0μm。并首次从杨梅根瘤共生固氮的内生菌中通过PCR反应克隆了2675bp的固氮酶结构基因,包括nifH和nifD全长基因及nifK基因片段,对其nifH和nifD基因的核苷酸序列分析结果表明,其核苷酸与已报道的Frankia菌株同类基因的核苷酸的同源性高,达89%以上。861bp的nifH基因开放阅读框架和1458bp的nifD基因开放阅读框架的氨基酸序列与已报道的其他Frankia菌株同类基因的氨基酸序列的同源性分别为92%以上和89%以上,特别是起重要作用的氨基酸残基非常保守。nifH、nifD及nifK基因是连锁在一起的,nifH和nifD及nifD和nifK之间的间隔序列分别为49bp和205bp,与已报道的Frankia菌株同类基因之间的间隔序列在长度和同源性上差异较大,因而杨梅根瘤共生固氮的内生菌与其它属植物根瘤共生固氮内生菌及分离株存在菌株之间的差异。
For the first time, there were two types of endophytic vesicle structure in Myrica rubra by transmission electron microscopy, with or without septum, oval and diameter of 1.3-3.0 μm. And for the first time from the MyzusLamous symbiotic nitrogen fixation of endophyte by PCR reaction cloned 2675bp nitrogenase structural gene, including nifH and nifD full-length gene and nifK gene fragment, the nifH and nifD gene nucleotide sequence analysis showed that The nucleotide homology was higher than that of homologous genes of Frankia strains reported, accounting for more than 89%. The amino acid sequence of 861 bp open reading frame of nifH gene and 1458 bp nifD gene open reading frame share 92% or more and 89% or more homology with other reported homologous genes of Frankia strains, especially those with important functions Amino acid residues are very conserved. The nifH, nifD and nifK genes are linked together. The interval sequences between nifH and nifD, nifD and nifK are 49bp and 205bp, respectively. The interval sequence between homologous genes of Frankia strain and the reported sequence length and homology The differences are so great that there is a difference between endophytic symbiotic nitrogen-fixing endophytes of Myrica rubra and those of other genus Nodule symbiotic endophytic nitrogen-fixing endophytes and isolates.