Open AccessMutants of Anabaena variabilis requiring high levels of molybdate for nitrate reductase and nitrogenase activities
Author(s) -
MartínNieto José,
Flores Enrique,
Herrero Antonia
Publication year - 1990
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.1574-6968.1990.tb13825.x
Subject(s) - anabaena variabilis , nitrogenase , nitrate reductase , molybdate , molybdenum cofactor , molybdenum , mutant , biochemistry , ribonucleotide reductase , cofactor , chemistry , nitrate , reductase , enzyme , biology , cyanobacteria , nitrogen fixation , gene , inorganic chemistry , bacteria , genetics , protein subunit , organic chemistry
Mutants of the dinitrogen‐fixing cyanobacterium Anabaena variabilis have been isolated which are unable to synthesize active nitrate reductase under normal, low‐molybdenum growth conditions. One of the mutants was also impaired in nitrogenase activity. Both deficiencies were restorable by the addition of high levels of molybdate to the medium. The existence in A. variabilis of common and specific genes for the synthesis of iron‐molybdenum and molybdenum cofactors, i.e. of a branched molybdenum assimilation pathway, is inferred.