The effects of nitrogen sources on the expression of Nif gene in Klebsiella pneumoniae Nif-Lac fusants = Klebsiella pneumoniae nif-lac 융합변이주의 질소고정 유전자 발현에 미치는 질소원의 효과

Abstract

The effects of various nitrogen sources on the expression of nif gene were investigated using nif-lac fusants of Klebsiella pneumoniae. K. pneumoniae UN 2979 was infected with Mudl lysate prepared by heat induction of K. pneumoniae UN 4482. About 80 nif-lac fusants were isolated and designated as LX series. In the presence of NH4+, beta-galactosidase activities on nif-lac fusants were greatly repressed. Amino acids, such as serine, glutamine and asparagine, were found to support the growth of K. pneumoniae M5al quite well, and showed a repressive effect on beta-galactosidase activities of nif-lac fusants LX-9 and LX-22 in NFHM