title: N-acetylglucosamine 6-phosphate deacetylase (nagA) is required for N-acetyl glucosamine assimilation in Gluconacetobacter xylinus.
abstract: Metabolic pathways for amino sugars (N-acetylglucosamine; GlcNAc and glucosamine; Gln) are essential and remain largely conserved in all three kingdoms of life, i.e., microbes, plants and animals. Upon uptake, in the cytoplasm these amino sugars undergo phosphorylation by phosphokinases and subsequently deacetylation by the enzyme N-acetylglucosamine 6-phosphate deacetylase (nagA) to yield glucosamine-6-phosphate and acetate, the first committed step for both GlcNAc assimilation and amino-sugar-nucleotides biosynthesis. Here we report the cloning of a DNA fragment encoding a partial nagA gene and its implications with regard to amino sugar metabolism in the cellulose producing bacterium Glucoacetobacter xylinus (formally known as Acetobacter xylinum). For this purpose, nagA was disrupted by inserting tetracycline resistant gene (nagA::tet(r); named as ΔnagA) via homologous recombination. When compared to glucose fed conditions, the UDP-GlcNAc synthesis and bacterial growth (due to lack of GlcNAc utilization) was completely inhibited in nagA mutants. Interestingly, that inhibition occured without compromising cellulose production efficiency and its molecular composition under GlcNAc fed conditions. We conclude that nagA plays an essential role for GlcNAc assimilation by G. xylinus thus is required for the growth and survival for the bacterium in presence of GlcNAc as carbon source. Additionally, G. xylinus appears to possess the same molecular machinery for UDP-GlcNAc biosynthesis from GlcNAc precursors as other related bacterial species.
authors.affiliation: Department of Biomedical Engineering , Tufts University, Medford, Massachusetts, United States of America.
authors.forename: Vikas
authors.initials: V
authors.lastname: Yadav
authors.forename: Bruce
authors.initials: B
authors.lastname: Panilaitis
authors.forename: Hai
authors.initials: H
authors.lastname: Shi
authors.forename: Keiji
authors.initials: K
authors.lastname: Numuta
authors.forename: Kyongbum
authors.initials: K
authors.lastname: Lee
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives / Q000096:biosynthesis*; D000581:Amidohydrolases / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000378:metabolism; D041822:Gluconacetobacter xylinus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D050296:Microbial Viability; D018625:Microscopy, Atomic Force; D008969:Molecular Sequence Data; D009154:Mutation; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014539:Uridine Diphosphate Sugars / Q000096:biosynthesis
chemical_list: D001426:Bacterial Proteins; D014539:Uridine Diphosphate Sugars; C083732:uridine diphosphate N-acetyllactosamine; C010004:N-acetylglucosamine 6-phosphate; D000581:Amidohydrolases; C018717:N-acetylglucosamine-6-phosphate deacetylase; D000117:Acetylglucosamine