TEMPERATURE CONTROL OF NITROGEN-FIXATION IN KLEBSIELLA-PNEUMONIAE

被引:53
作者
HENNECKE, H [1 ]
SHANMUGAM, KT [1 ]
机构
[1] UNIV CALIF DAVIS,DEPT AGRON & RANGE SCI,DAVIS,CA 95616
关键词
Gene expression; Klebsiella pneumoniae; Microbial ecology; Nitrogen fixation; Nitrogenase; Protein synthesis; Regulation;
D O I
10.1007/BF00406659
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
At growth temperatures above 37°C, Klebsiella pneumoniae does not grow in a medium containing N2 or NO3-as nitrogen sources. However, both the growth in the presence of other nitrogen sources as well as the in vitro nitrogenase activity are not affected at this temperature. The inability to fix N2 at high temperature is due to the failure of the cells to synthesize nitrogenase and other nitrogen fixation (nif) gene encoded proteins. When cells grown under nitrogen fixing conditions at 30°C were shifted to 39°C, there was a rapid decrease of the rate of de novo biosynthesis of nitrogenase (component 1), nitrogenase reductase (component 2), and the nifJ gene product. There was no degradation of nitrogenase at the elevated temperature since preformed enzyme remained stable over a period of at least 3 h at 39°C. Thus, temperature seems to represent a third control system, besides NH4+and O2, governing the expression of nif genes of K. pneumoniae. © 1979 Springer-Verlag.
引用
收藏
页码:259 / 265
页数:7
相关论文
共 30 条