Abstract
Nitrogen assimilation in Rhodobacter capsulatus has been shown to proceed via the coupled action of glutamine synthetase (GS) and glutamate synthase (GOGAT) with no measurable glutamate dehydrogenase (GDH) present. We have recently isolated a novel class of mutants of R. capsulatus strain B100 that lacks a detectable GOGAT activity but is able to grow at wild type rates under nitrogen-fixing conditions. While NH +4 -supported growth in the mutants was normal under anaerobic/photosynthetic conditions, the growth rate was decreased under aerobic conditions. Ammonium and methylammonium uptake experiments indicated that there was a clear difference in the ammonium assimilatory capabilities in these mutants under aerobic versus anaerobic growth. Regulation of expression of a nifH : : lacZ fusion in these mutants was not impaired. The possible existence of alternative ammonium assimilatory pathways is discussed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bender RA, Janssen KA, Resnick AD, Blumenberg M, Foor F. Magasanik B (1977) Biochemical parameters of glutamine synthetase from Klebsiella aerogenes. J Bacteriol 129: 1001–1009
Bertani G (1951) Studies on lysogenesis. I. The mode of phage liberation by lysogenic Escherichia coli. J Bacteriol 62: 293–300
Brana AF, Paiva N, Demain AL (1986) Pathways and regulation of ammonium assimilation in Streptomyces clavuligerus. J Gen Microbiol 132: 1305–1317
Bravo A, Mora J (1988) Ammonium assimilation in Rhizobium phaseoli by the glutamine synthetase-glutamate synthase pathway. J Bacteriol 170: 980–984
Brown CM, Herbert RA (1977) Ammonia assimilation in members of the Rhodospirillaceae. FEMS Microbiol Lett 1: 43–46
Caballero FJ, Cardenas J, Castillo F (1989a) Purification and properties of l-alanine dehydrogenase of the phototrophic bacterium Rhodobacter capsulatus E1F1. J Bacteriol 171: 3205–3210
Cabellero FJ, Igeno I, Cardenas J, Castillo F (1989b) Regulation of reduced nitrogen assimilation in Rhodobacter capsulatus E1F1. Arch Microbiol 152: 508–511
Chaney AL, Marbach EP (1962) Modified reagents for determination of urea and ammonia. Clin Chem 8: 130–132
Chen C, VanBaalen C, Tabita RF (1987) DL-7-azatryptophan and citrulline metabolism in the cyanobacterium Anabaena sp. strain 1F. J Bacteriol 169: 1114–1119
Cullimore JV, Sims AP (1981) Occurrence of two forms of glutamate synthase in Clamydomonas reinhardtii. Phytochemistry 20: 597–600
Ditta G, Stanfield S, Corbin D, Helinski DR (1980) Broad host range DNA cloning system for Gram-negative bacteria: construction of a gene bank of Rhizobium meliloti Proc Natl Acad Sci USA 77: 7347–7351
Johansson BC, Gest H (1976) Inorganic nitrogen assimilation by the photosynthetic bacterium Rhodopseudomonas capsulata. J Bacteriol 128: 683–688
Johansson BC, Gest H (1977) Adenylylation/deadenylylation control of the glutamine synthetase of Rhodopseudomonas capsulata. Eur J Biochem 81: 365–371
Kranz RG, Haselkorn R (1985) Characterization of nif regulatory genes in Rhodopseudomonas capsulata using lac gene fusions. Gene 40: 203–215
Lea PJ, Miflin BJ (1975) Glutamate synthase in Blue-Green algae. Biochem Soc Trans 3: 381–384
Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193: 265–275
Marrs B (1974) Genetic recombination in Rhodopseudomonas capsulata. Proc Natl Acad Sci USA 71: 971–973
Meynell GG, Meynell E (1965) Theory and practice in experimental bacteriology, 2nd edn. Cambridge University Press, Cambridge, UK
Miller J (1972) Experiments in molecular genetics. Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
Moreno-Vivian C, Cejudo EJ, Cardenas J, Castillo F (1983) Ammonia assimilation pathways in Rhodopseudomonas capsulata E1F1. Arch Microbiol 136: 147–151
Morsdorf G, Kaltwasser H (1989) Ammonium assimilation in Proteus vulgaris, Bacillus pasteurii, and Sporosarcina ureae. Arch Microbiol 152: 125–131
Naider F, Bohak Z, Yariv J (1972) Reversible alkylation of a methionyl residue near the active site of β-galactosidase. Biochemistry 11: 3202–3208
Rapp BJ, Landrum DC, Wall JD (1986) Methylammonium uptake by Rhodobacter capsulatus. Arch Microbiol 146: 134–141
Reitzer LJ, Magasanik B (1987) Ammonia assimilation and the biosynthesis of glutamine, glutamate, aspartate, asparagine, l-alanine, and d-alanine. In: Neidhardt FC, Ingraham JL, Low KB, Magasanik B, Schaechter M, Umbarger HE (eds) Escherichia coli and Salmonella typhimurium: cellular and molecular biology. American Society for Microbiology, Washington, D.C., pp 302–320
Romero F, Quintero A, Roldan JM (1989) Role of glutamine as a direct co-repressor of glutamine synthetase in Rhodobacter capsulatus E1F1. FEMS Microbiol Lett 58: 111–114
Shapiro BM, Stadtman ER (1970) Glutamine synthetase (Escherichia coli). In: Colowick SP, Kaplan NO (eds) Methods in enzymology, vol 17A. Academic Press. New York London, pp 910–922
Sharak-Genthner BR, Wall JD (1985) Ammonium uptake in Rhodopseudomonas capsulata. Arch Microbiol 141: 219–224
Tolxdorff-Neutzling R, Klemme J-H (1982) Metabolic role and regulation of l-alanine dehydrogenase in Rhodopseudomonas capsulata. FEMS Microbiol Lett 13: 155–159
Tyler B (1978) Regulation of the assimilation of nitrogen compounds. Ann Rev Biochem 47: 1127–1162
Wall JD, Gest H (1979) Derepression of nitrogenase activity in glutamine auxotrophs of Rhodopseudomonas capsulata. J Bacteriol 137: 1459–1463
Wallsgrove RM, Harel E, Lea PJ, Miflin BJ (1977) Studies on glutamate synthase from the leaves of higher plants. J Exp Bot 28: 588–596
Weaver PF, Wall JD, Gest H (1975) Characterization of Rhodopseudomonas capsulata. Arch Microbiol 105: 207–216
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Borghese, R., Wall, J.D. A novel class of ammonium assimilation mutants of the photosynthetic bacterium Rhodobacter capsulatus . Arch. Microbiol. 157, 361–366 (1992). https://doi.org/10.1007/BF00248682
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00248682