N-Acetyl-D-mannosamine (ManNAc) and N-acetyl-D-glucosamine (GlcNAc) are the essential precursors of N-acetylneuraminic acid (NeuAc), the specific monomer of polysialic acid (PA), a bacterial pathogenic determinant. Escherichia coli K1 uses both amino sugars as carbon sources and uptake takes place through the mannose phosphotransferase system transporter, a phosphoenolpyruvate-dependent phosphotransferase system that shows a broad range of specificity. Glucose, mannose, fructose, and glucosamine strongly inhibited the transport of these amino-acetylated sugars and GlcNAc and ManNAc strongly affected ManNAc and GlcNAc uptake, respectively. The ManNAc and the GlcNAc phosphorylation that occurs during uptake affected NeuAc synthesis in vitro. These findings account for the low in vivo PA production observed when E. coli K1 uses ManNAc or GlcNAc as a carbon source for growth.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s0014-5793(01)03318-x | DOI Listing |
Molecules
November 2024
Department of Life and Environmental Sciences, Cittadella Universitaria di Monserrato, Blocco A, Room 13, 09042 Monserrato, Italy.
GNE myopathy, also known as hereditary inclusion body myopathy (HIBM), is a rare genetic muscle disorder marked by a gradual onset of muscle weakness in young adults. GNE myopathy (GNEM) is caused by bi-allelic variants in the UDP--acetylglucosamine 2-epimerase (UDP-GlcNAc 2-epimerase)/-acetylmannosamine kinase (ManNAc kinase) gene (), clinically resulting in the loss of ambulation within 10-20 years from the onset of the initial symptoms. The disease's mechanism is poorly understood and non-invasive biomarkers are lacking, hindering effective therapy development.
View Article and Find Full Text PDFFront Mol Biosci
September 2024
Department of Chemistry, Institute of Biochemistry, NanoGlycobiology Research Group, Universität für Bodenkultur Wien, Vienna, Austria.
Biochemistry
May 2024
Department of Internal Medicine I, Medical University of Vienna, Waehringer Guertel 18-20, Vienna A-1090, Austria.
Cyanovirin-N (CV-N) binds high-mannose oligosaccharides on enveloped viruses with two carbohydrate-binding sites, one bearing high affinity and one low affinity to Manα(1-2)Man moieties. A tandem repeat of two CV-N molecules (CVN2) was tested for antiviral activity against human immunodeficiency virus type I (HIV-1) by using a domain-swapped dimer. CV-N was shown to bind -acetylmannosamine (ManNAc) and -acetyl-d-glucosamine (GlcNAc) when the carbohydrate-binding sites in CV-N were free to interact with these monosaccharides independently.
View Article and Find Full Text PDFJ Biomol Struct Dyn
March 2024
Amity Institute of Neuropsychology & Neurosciences, Amity University, Noida, India.
The activity of UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE) is essential for the biosynthesis of sialic acid, which is involved in cellular processes in health and diseases. GNE contains an N-terminal epimerase domain and a C-terminal kinase domain (N-acetylmannosamine kinase, MNK). Mutations of the GNE protein led to hypoactivity of the enzyme and cause sialurea or autosomal recessive inclusion body myopathy/Nonaka myopathy.
View Article and Find Full Text PDFBiochemistry
March 2024
Department of Chemistry, Texas A&M University, College Station, Texas 77845, United States.
is a human pathogen and a leading cause of food poisoning in North America and Europe. The exterior surface of the bacterial cell wall is attached to a polymeric coat of sugar molecules known as the capsular polysaccharide (CPS) that helps protect the organism from the host immune response. The CPS is composed of a repeating sequence of common and unusual sugar residues.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!