Open AccessConstruction of a recF deletion mutant of Azotobacter vinelandii and its characterization
Author(s) -
Badran Hema,
Sohoni Rashmi,
Venkatesh T.V,
Das H.K
Publication year - 1999
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.1574-6968.1999.tb13591.x
Subject(s) - azotobacter vinelandii , mutant , biology , genetics , mutation , gene , microbiology and biotechnology , southern blot , nitrogenase , nitrogen fixation , bacteria
A deletion was engineered in the cloned recF gene by digestion with suitable restriction endonucleases and a tetracycline resistance gene cartridge was inserted. The mutation was subsequently transferred to the Azotobacter vinelandii chromosome by double cross‐over under pressure of tetracycline selection. A recF recA mutant was also constructed in a similar manner. The mutations were found to be stable and mutation of the wild‐type recF gene was confirmed by Southern blot hybridization. Both the mutants were UV sensitive and recombination deficient. Mutations in genes involved in nitrogen fixation in A. vinelandii are rather frequent and obtained comparatively easily despite of the presence of multiple identical chromosomes in A. vinelandii . It has been speculated that some kind of ‘homogenotization’ process operates which is responsible for the ‘transmission’ of mutation from one chromosome to all the chromosomes. This process is not affected by a mutation in recF or recA or in both recF and recA .