玉米根际联合固氮菌57-7菌株基本特性的研究

THE STUDY OF BASIC CHARACTERIZATION ON MAIZE RHIZOSPHERE ASSOCIATIVE NITROGEN FIXATION BACTERIA 57-7

从四川省灌县地区的玉米根际分离到一株发酵型细菌，编号５７－７。经鉴定为日勾维肠杆菌，其最适生长温度为３０℃，最适生长ｐＨ为８．０。用＾１５Ｎ及乙炔还原测定，证实有固氮酶活性。乙炔还原活性最高达８３５４ｎｍｌＣ２Ｈ４·ｍｇ蛋白＾－１·ｈ＾－１。研究了Ｏ２、ＮＨ＾＋４、ＮａＣｌ对固氮酶合成、固氮酶活性及菌株生长的影响。

57-7 was isolated and purified from maize roots grown in Sichuan province.Withthe ^(15)N_2 experiment and acetylene reduction experiment,it was confirmed to be a N_2-fixing bacteria.The optinum growth temperature and pH were measured.The highestspecific activity was 8354 nmoi C_2H_4·mg^(-1) protein·h^(-1).The effects of O_2,NH_4^+,NaCIon the activity of Nase and synthesis of Nase were studied.