黑木相思根瘤菌ACC脱氨酶活性的研究

ACC deaminase activity of rhizobia associated with Acacia melanoxylon

根瘤菌能够利用1-氨基环丙烷-1羧酸(ACC)脱氨酶催化ACC脱氨基,从而降低植物体内抑制其生长的乙烯含量,促进植物生长。本研究采用茚三酮比色法测定菌株的ACC脱氨酶活性并对其acd S基因进行了系统发育分析。结果表明,扩增174株供试菌株中,151株检测出ACC脱氨酶活性,但酶活性差异较大。121株扩增出acd S基因,菌株的系统发育关系与地理来源具有相关性,中慢生根瘤菌属菌株的acd S基因具有明显的保守性。菌株ACC脱氨酶活性的高低与acd S基因存在与否的相关性有待进一步研究。ACC脱氨酶活性的检测方法将为快速筛选高效根瘤菌菌株提供可靠的理论依据。

Rhizobia can catalyze the ACC deaminase by using -aminocyclopropane-l-carboxylate （ACC） deaminase, thereby reducing the ethylene content in the plants that inhibits the growth of rhizobia and promoting plant growth. The tested bacterial strains were mensurated and their acdS gene＇s phylogenetic development were analyzed. The results show that among the isolated 174 isolates, 151 strains showed ACC deaminase activity, but there were rather differences in enzyme activity; however, the acdS gene of 121 strains were detected which were conserved in Mesorhizobium genus; the phylogeny of acdS genes was significantly correlated with geographical origin. A further research on the correlation between the level of ACC deaminase activity and the prevalence of acdS genes is urgently needed. The test method of ACC deaminase will provide a reliable theoretical foundation for rapidly culling high efficient rhizobia strains.