4acf

Structural highlights

Function

GLN1B_MYCTU Involved in nitrogen metabolism via ammonium assimilation. Catalyzes the ATP-dependent biosynthesis of glutamine from glutamate and ammonia (PubMed:7937767, PubMed:12819079). Also able to use GTP (PubMed:7937767). D-glutamate is a poor substrate, and DL-glutamate shows about 50% of the standard specific activity (PubMed:7937767). Also plays a key role in controlling the ammonia levels within infected host cells and so contributes to the pathogens capacity to inhibit phagosome acidification and phagosome-lysosome fusion (PubMed:7937767, PubMed:12819079). Involved in cell wall biosynthesis via the production of the major component poly-L-glutamine (PLG) (PubMed:7937767, PubMed:10618433). PLG synthesis in the cell wall occurs only in nitrogen limiting conditions and on the contrary high nitrogen conditions inhibit PLG synthesis (Probable).^{[1] [2] [3] [4]}

See Also

• Glutamine synthetase 3D structures

References

1. ↑ Harth G, Zamecnik PC, Tang JY, Tabatadze D, Horwitz MA. Treatment of Mycobacterium tuberculosis with antisense oligonucleotides to glutamine synthetase mRNA inhibits glutamine synthetase activity, formation of the poly-L-glutamate/glutamine cell wall structure, and bacterial replication. Proc Natl Acad Sci U S A. 2000 Jan 4;97(1):418-23. PMID:10618433 doi:10.1073/pnas.97.1.418
2. ↑ Tullius MV, Harth G, Horwitz MA. Glutamine synthetase GlnA1 is essential for growth of Mycobacterium tuberculosis in human THP-1 macrophages and guinea pigs. Infect Immun. 2003 Jul;71(7):3927-36. PMID:12819079 doi:10.1128/IAI.71.7.3927-3936.2003
3. ↑ Harth G, Clemens DL, Horwitz MA. Glutamine synthetase of Mycobacterium tuberculosis: extracellular release and characterization of its enzymatic activity. Proc Natl Acad Sci U S A. 1994 Sep 27;91(20):9342-6. PMID:7937767 doi:10.1073/pnas.91.20.9342
4. ↑ Harth G, Horwitz MA. Expression and efficient export of enzymatically active Mycobacterium tuberculosis glutamine synthetase in Mycobacterium smegmatis and evidence that the information for export is contained within the protein. J Biol Chem. 1997 Sep 5;272(36):22728-35. PMID:9278431 doi:10.1074/jbc.272.36.22728