EC Number   |
General Information |
Reference |
|---|
    5.1.3.14 | physiological function |
2-epimerase MnaA interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. Besides MnaA, Staphylococcus aureus maintains a second 2-epimerase involved in serotype 5 capsular polysaccharide (CP5) synthesis, Cap5P. MnaA and Cap5P provide compensatory WTA functional roles in Staphylococcus aureus. MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSA. Overlapping functional activity of MnaA and Cap5P in Staphylococci |
-, 755205 |
| 5.1.3.14 | physiological function |
2-epimerase MnaA interconverts UDP-GlcNAc and UDP-ManNAc to modulate substrate levels of TarO and TarA wall teichoic acid (WTA) biosynthesis enzymes. MnaA serves as the sole 2-epimerase required for WTA biosynthesis in Staphylococcus epidermidis. MnaA and other enzymes of WTA biosynthesis are required for biofilm formation in MRSE |
-, 755205 |
| 5.1.3.14 | more |
a comparison of the crystal structures in open and closed conformations shows that upon UDP and UDPGlcNAc binding, the enzyme undergoes conformational changes involving a rigid-body movement of the C-terminal domain. Comparison of the crystal structures of Methanocaldococcus jannaschii and of Bacillus subtilis. Structural superimposition of closed-form and open-form Mj-epimerase. Homologous enzyme structure comparisons, overview |
749249 |
| 5.1.3.14 | evolution |
Bacillus anthracis gneY and gneZ encode nearly identical UDP-GlcNAc 2-epimerase enzymes that catalyze the reversible conversion of UDPGlcNAc and UDP-ManNAc |
748089 |
| 5.1.3.14 | more |
comparison of the crystal structures of Methanocaldococcus jannaschii in open and closed conformations and of Bacillus subtilis. Homologous enzyme structure comparisons, overview |
-, 749249 |
| 5.1.3.14 | malfunction |
deletions of early wall teichoic acid (WTA) biosynthetic enzymes are nonlethal, but cause diverse attenuated virulence phenotypes, deletions of later steps in WTA biosynthesis are not generally tolerated and the enzymes are normally essential for growth, an essential gene paradox. The beta-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSA infection. Complementing DELTAcap5P mnaASa P12L and DELTAcap5P mnaASa Y194* with either cap5P or mnaASa reintroduced on an inducible plasmid restores WTA polymer levels, resistance to each of the beta-lactams tested, and wild-type sensitivity to L638 |
-, 755205 |
| 5.1.3.14 | malfunction |
deletions of early wall teichoic acid (WTA) biosynthetic enzymes are nonlethal, but cause diverse attenuated virulence phenotypes, deletions of later steps in WTA biosynthesis are not generally tolerated and the enzymes are normally essential for growth, an essential gene paradox. The beta-lactam antibiotic imipenem exhibits restored bactericidal activity against mnaA mutants in vitro and concomitant efficacy against 2-epimerase defective strains in a mouse thigh model of MRSE infection |
-, 755205 |
| 5.1.3.14 | malfunction |
enzyme deficiency causes the disease sialuria in humans. Hereditary inclusion body myopathy, h-IBM, is also a disease caused by different mutations in the GNE gene, it is an autosomal recessive neuromuscular disorder characterized by adult onset, slowly progressive skeletal muscle weakness, and typical histological features as rimmed vacuoles and filamentous inclusions. Sialuria is caused by the loss of feedback control of UDP-GlcNAc 2-epimerase activity due to the mutation of only one of the two arginine residues 263 and 266. Sialuria leads to massive production of free Neu5Ac, which accumulates in the cytoplasm and results in mental retardation and hepatomegaly |
702507 |
| 5.1.3.14 | metabolism |
GNE catalyzes the first two committed, rate-limiting steps in the biosynthesis of N-acetylneuraminic acid, i.e. sialic acid |
703912 |
| 5.1.3.14 | metabolism |
GNE catalyzes the first two steps of sialic acid biosynthesis in the cytosol |
703905 |
