Characteristics of glutamine synthetase I and II mutants of Rhizobium.

Keister, Donald L.; Jones, Ben; Kondorosi, Ádám; Sváb, Zóra

doi:10.2323/jgam.33.267

J. Gen. Appl. Microbiol.

1987

DOI: 10.2323/jgam.33.267

|View full text |Cite

Characteristics of glutamine synthetase I and II mutants of Rhizobium.

Donald L. Keister

Ben Jones

Ádám Kondorosi

et al.

Abstract: MutantsCharacteristic isoenzymes of glutamine synthetase (GS) are found in the Rhizobiaceae which includes Agrobacterium, 12,13). GSI has many properties similar to the GS found in enteric bacteria (3) while GSII appears solely in the Rhizobiaceae (7) and has properties distinctly different from GSI (3,4). LUDWIG (12, 13), MORETT et al. (14), and de BRUIJN et al. (1) have isolated strains of Rhizobium and Bradyrhizobium which were GSI + GSII -illustrating that GSI alone is fully competent to supply the cell wi… Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

1989

1994

Publication Types

Select...

Article3

Relationship

Self Cite0

Independent3

Authors

Journals

Cited by 3 publications

(1 citation statement)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A strain with mutations in both genes cannot form nodules unless glutamine is added to the plant medium; these nodules are Fix- (8). Other mutants lacking one or both GS activities have been isolated (25,30), but the mutations leading to the GS-phenotype have not been precisely defined.…”

mentioning

confidence: 99%

Isolation, characterization, and complementation of Rhizobium meliloti 104A14 mutants that lack glutamine synthetase II activity

1989

View full text Add to dashboard Cite

The glutamine synthetase (GS)-glutamate synthase pathway is the primary route used by members of the family Rhizobiaceae to assimilate ammonia. Two forms of glutamine synthetase, GSI and GSII, are found in Rhizobium and Bradyrhizobium species. These are encoded by the glnA and ginl genes, respectively. Starting with a Rhizobium meliloti ginA mutant as the parent strain, we isolated mutants unable to grow on minimal medium with ammonia as the sole nitrogen source. For two auxotrophs that lacked any detectable GS activity, R. meliloti DNA of the mutated region was cloned and partially characterized. Lack of cross-hybridization indicated that the cloned regions were not closely linked to each other or to ginA; they therefore contain two independent genes needed for GSII synthesis or activity. One of the cloned regions was identified as glnll. An R. meliloti glnlI mutant and an R. meliloti glnA ginlI double mutant were constructed. Both formed effective nodules on alfalfa. This is unlike the B. japonicum-soybean symbiosis, in which at least one of these GS enzymes must be present for nitrogen-fixing nodules to develop. However, the R. meliloti double mutant was not a strict glutamine auxotroph, since it could grow on media that contained glutamate and ammonia, an observation that suggests that a third GS may be active in this species.

show abstract

mentioning

confidence: 99%

Isolation, characterization, and complementation of Rhizobium meliloti 104A14 mutants that lack glutamine synthetase II activity

1989

View full text Add to dashboard Cite

show abstract

Rhizobium meliloti 1021 has three differentially regulated loci involved in glutamine biosynthesis, none of which is essential for symbiotic nitrogen fixation

Bruijn¹,

Rossbach²,

Schneider³

et al. 1989

J Bacteriol

103

View full text Add to dashboard Cite

show abstract

Molecular Genetics of the Glutamine Synthetases in Rhizobium Species

Espı́n

Moreno

Guzmán

1994

Critical Reviews in Microbiology

View full text Add to dashboard Cite

Soil bacteria of the genus Rhizobium and Bradyrhizobium establish symbiotic interactions with leguminous plants that result in the formation of specialized structures, the nodules, in which the bacteria differentiate into bacteroids and fix nitrogen. Rhizobial glutamine synthetase (GS) activity is very low in the nodule. The ammonia produced by the bacteroids is exported to the plant cell, where it is assimilated by the GS from the plant, whereas in the free-living state, Rhizobium and Bradyrhizobium species assimilate ammonia for growth. Another characteristic of these species is that they possess two glutamine synthetase isozymes, known as GSI and GSII. A third glutamine synthetase isozyme, called GSIII, has been found in R. meliloti and R. etli.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Characteristics of glutamine synthetase I and II mutants of Rhizobium.

Cited by 3 publications

References 6 publications

Isolation, characterization, and complementation of Rhizobium meliloti 104A14 mutants that lack glutamine synthetase II activity

Isolation, characterization, and complementation of Rhizobium meliloti 104A14 mutants that lack glutamine synthetase II activity

Rhizobium meliloti 1021 has three differentially regulated loci involved in glutamine biosynthesis, none of which is essential for symbiotic nitrogen fixation

Molecular Genetics of the Glutamine Synthetases in Rhizobium Species

Contact Info

Product

Resources

About