Characterization of Methylammonium/Ammonium Transport in Mutant Strains of Anabaena variabilis Resistant to Ammonium Analogues

Ammonium (methylammonium) transport by heterocysts and vegetative cells of Anabaena variabilis.

Transport of the ammonium analogue [(14)C]methylammonium was similar in non-growing, fully differentiated heterocysts as compared to vegetative, multiplying cells of the filamentous cyanobacterium Anabaena variabilis. NH(4)(+) inhibited uptake into the cells and released accumulated methylammonium from the cells. These observations suggest that the main function of ammonium transport in heteroc...

Potassium ion transport and electrogenesis in Anabaena variabilis.

Response of multiple herbicide resistant strain of diazotrophic cyanobacterium, Anabaena variabilis, exposed to atrazine and DCMU.

Effect of two photosynthetic inhibitor herbicides, atrazine (both purified and formulated) and [3-(3,4-dichlorophenyl)-1,1-dimethyl urea] (DCMU), on the growth, macromolecular contents, heterocyst frequency, photosynthetic O2 evolution and dark O2 uptake of wild type and multiple herbicide resistant (MHR) strain of diazotrophic cyanobacterium A. variabilis was studied. Cyanobacterial strains sh...

Bioenergetics Studies of the Cyanobacterium Anabaena variabilis

A cell-free system exhibiting both photophosphorylation (P /2e = 1) and oxidative phosphoryla­ tion (P/O up to 0 .8 ) is described for the cyanobacterium Anabaena variabilis. NADH and N A D PH were found to be equally effective as electron donors for oxidative phosphorylation. Low concentrations of U H D B T , an inhibitor of the cytochrome blc complex of mitochondria and chloroplasts. were fou...

Isolation and Characterization of Nitrogenase-Derepressed Mutant Strains of Cyanobacterium Anabaena variabilist

A positive selection method for isolation of nitrogenase-derepressed mutant strains of a filamentous cyanobacterium, Anabaena variabilis, is described. Mutant strains that are resistant to a glutamate analog, L-methionine-D,L-sulfoximine, were screened for their ability to produce and excrete NH4' into medium. Mutant strains capable of producing nitrogenase in the presence of NH4' were selected...