导入四碳二羧酸转移酶基因对费氏中华根瘤菌共和固氮效率的影响

将来自苜蓿中华根瘤菌（Ｓｉｎｏｒｈｉｚｏｂｉｕｍ ｍｅｌｉｌｏｔｉ）的四碳二羧酸转移酶基因（ｄｃｔＡＢＤ）经ｐＩＪ２９２５克隆到广宿主、稳定性质粒ｐＴＲ１０２上，获得诱导型表达的重组质粒ｐＨＮ２０２。在此基础上再引入来自ｐＤＢ３０所含的发光酶基因（ｌｕｘＡＢ）作分子标记，以ｐＴＲ１０２为基础建成带有ｄｃｔＡＢＤ和ｌｕｘＡＢ的重组质粒ｐＨＮ２０５。＃? ｄｇ ｕｓ ｓｇ ｒｕｖ ｗｇｋ ｌｆｔｑ，ｕ

The Introduction of dctABD Genes into Sinorhizobium fredii and Its Effect on Symbiotic Nitrogen Fixation Efficiency

The 5 75kb DNA fragment containing C4 dicarboxylic acid transport ( dctABD ) genes isolated from Sinorhizobium meliloti was subcloned into the stable broad host plasmid pTR102 through pIJ2925, A inducible expression recombinant plasmid pHN202 was obtained The reporter gene luxAB from plasmid pDB30 was also inserted into pHN202 and the recombinant plasmid pHN205 was constructed and then introduced into Sinorhizobium fredii HN01, YC4 and GR3 by tri parental mating Plant pot experiments were carried out for the recipient strains and their transconjugants It was confirmed that recombinant strains HN01(pHN205) and GR3(pHN205) could significantly increase the shoot dry weight(biomass) and total nitrogen content of the plant with soybean varieties of Ningzhen N0 1 and Chuanzao No 1 respectively Transconjugant YC4 (pHN205) could also significantly increase the shoot dry weight(biomass), total nitrogen content of the plant and root nodule fresh weight with soybean variety Heilong 33 The results suggested that the effect of dctABD genes on the symbiotic nitrogen fixation efficiency was relevant to many factors such as soybean varieties, soil fertility and recipient rhizobia The results of colony and nodule lighting detection indicated that the recombinant plasmid pHN205 was stable in S fredii tested under both free living and symbiotic condition