14C-labelling of glutamine synthetase and Fe protein of nitrogenase in toluene-treated cells of Rhodopseudomonas capsulata

Regulation of N2 Fixation and Ammonia Assimilation in Rhodopseudomonas sphaeroides f. sp. denitrificans. Role of Glutamine

“…denitrzjicans, determined by focusing on polyacrylamide slab gel with ampholines from pH 4.0 to 6.0, was found to be 5.3. This value is slightly lower than that for glutamine synthetase from R. capsulata (Michalski et al, 1983), and higher than that for the R. sphaeroides enzyme (Engelhardt & Klemme, 1982).…”

“…sphaeroides f. sp. denitrificans grown photoheterotrophically with 15 ~M -N H , C I were purified according to Alef et al (1981 b) with modifications described by Michalski et al (1983).…”

“…This effect is reversed when the ammonia has been utilized (Johansson & Gest, 1977;Alef et al, 1981a). Glutamine (Jones & Monty, 1979;Falk et al, 1982;Haaker et al, 1982;Michalski et al, 1983) and/or glutamine synthetase (Johansson & Gest, 1977;Hilmer & Falbusch, 1979;Yoch & Cantu, 1980), rather than free ammonia, have been implicated in these regulatory mechanisms. Hillmer & Falbusch (1980) suggested that nitrogenase is under negative control of the adenylylated form of glutamine synthetase.…”

Purification, Properties and Regulation of Glutamine Synthetase from Nitrobacter agilis

“…CTAB treatment of the cultures prior to harvest had no substantial effect on the state of adenylylation of glutamine synthetase. Relatively low concentrations of CTAB (2.5 pg ml-l ) were used compared to those used for other bacteria (Bender et al, 1977;Davies & Ormerod, 1982;Michalski et al, 1983) because higher concentrations resulted in cell lysis. This lysis may be associated with the low cell density of exponentially-grown cultures of N .…”

“…In enteric bacteria (Stadtman et al, 1970;Bender et al, 1977), photosynthetic bacteria (Johansson & Gest, 1977;Alef & Zumft, 198 1 ;Michalski et al, 1983) and rhizobia (Darrow & Knotts, 1977) the extent of transferase activity in the presence of 60 m~-MgCl, has been used as an indication of the degree of adenylylation of glutamine synthetase. The fully adenylylated enzyme is inactive in the presence of Mg2 + , whereas the deadenylylated enzyme is not affected.…”