Rhizobium glutamine synthetase

Cock, J.M., Mould, R.M., Bennett, M.J. Cullimore, J.V. (1990). Expression of glutamine synthetase genes in roots and nodules of Phaseolus vulgaris following changes in the ammonium supply and infection with various Rhizobium mutants. Plant Molecular Biology 14, 549-60. 

Wedler f al. (1978) have identified two forms of glutamine synthetase in Bacillus caldolytiens and Darrow and Knotts (1977) have shown two forms in Rhizobium japonicum and other free living root nodule bacteria. In both cases the two forms differ in their isoelectric points and stability. The work of Darrow and Knotts (1977) indicates that the two forms are not the result of differences in adenylation state of a single form. Type I appears similar to the E. coli enzyme in stability and in being susceptible to adenylation. Type II however is not adenylated and is more unstable. 

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