Open AccessNitrogen fixation by the unicellular cyanobacterium Gloeothece . Nitrogenase synthesis is only transiently repressed by oxygen
Author(s) -
Maryan Paul S.,
Eady Robert R.,
Chaplin Alan E.,
Gallon John R.
Publication year - 1986
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1986.tb01414.x
Subject(s) - nitrogenase , nitrogen fixation , chloramphenicol , oxygen , cyanobacteria , chemistry , biochemistry , biology , nitrogen , bacteria , antibiotics , organic chemistry , genetics
The extent of recovery of nitrogenase activity of Gloeothece transferred from an atmosphere of O 2 to air depended on the duration of exposure to O 2 . Activity recovered at increasing rates after up to 24 h exposure to O 2 and a lag before detection of activity, present after short (1 h) exposure times, disappeared with longer exposures. Synthesis of nitrogenase de novo was implicated, since chloramphenicol, tetracycline, or repressive levels of NH + 4 , prevented recovery of activity. Specific radioimmunoassay of the rate of synthesis of the MoFe protein of nitrogenase under O 2 correlated well with the activity measurements, and indicate that a shift from air to O 2 only transiently represses nitrogenase synthesis.