The N-acetyl-D-glucosaminylphosphatidylinositol De-N-acetylase of glycosylphosphatidylinositol biosynthesis is a zinc metalloenzyme.

Abstract

The de-N-acetylation of N-acetyl-D-glucosaminylphosphatidylinositol (GlcNAc-PI) is the second step of mammalian and trypanosomal glycosylphosphatidylinositol biosynthesis. Glycosylphosphatidylinositol biosynthesis is essential for Trypanosoma brucei, the causative agent of African sleeping sickness, and GlcNAc-PI de-N-acetylase has previously been validated as a drug target. Inhibition of the trypanosome cell-free system and recombinant rat GlcNAc-PI de-N-acetylase by divalent metal cation chelators demonstrates that a tightly bound divalent metal cation is essential for activity. Reconstitution of metal-free GlcNAc-PI de-N-acetylase with divalent metal cations restores activity in the order Zn(2+) > Cu(2+) > Ni(2+) > Co(2+) > Mg(2+). Site-directed mutagenesis and homology modeling were used to identify active site residues and postulate a mechanism of action. The characterization of GlcNAc-PI de-N-acetylase as a zinc metalloenzyme will facilitate the rational design of anti-protozoan parasite drugs.

• Authors: Michael D Urbaniak, Arthur Crossman, Tunhan Chang, Terry K Smith, Daan M F van Aalten, Michael A J Ferguson
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 280 Issue 24 Pg. 22831-8 (Jun 17 2005) ISSN: 0021-9258 [Print] United States
• PMID: 15817455 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• CD55 Antigens
• Cations
• Glycosylphosphatidylinositols
• Ions
• N-acetylglucosaminylphosphatidylinositol
• Phosphatidylinositols
• Recombinant Fusion Proteins
• Recombinant Proteins
• Green Fluorescent Proteins
• Amidohydrolases
• N-acetylglucosaminyl-phosphatidylinositol de-N-acetylase
• Zinc
• Alanine
• Acetylglucosamine

Topics

• Acetylglucosamine (analogs & derivatives, chemistry, metabolism)
• Alanine (chemistry)
• Amidohydrolases (chemistry, physiology)
• Amino Acid Sequence
• Animals
• Binding Sites
• CD55 Antigens (biosynthesis)
• Cations
• Cell-Free System
• Chromatography, High Pressure Liquid
• Crystallography, X-Ray
• Electrophoresis, Polyacrylamide Gel
• Escherichia coli (metabolism)
• Flow Cytometry
• Genetic Complementation Test
• Glycosylphosphatidylinositols (metabolism)
• Green Fluorescent Proteins (chemistry)
• Ions
• Models, Molecular
• Molecular Sequence Data
• Mutagenesis, Site-Directed
• Mutation
• Phosphatidylinositols (chemistry, metabolism)
• Plasmids (metabolism)
• Point Mutation
• Protein Conformation
• Protein Structure, Tertiary
• Rats
• Recombinant Fusion Proteins
• Recombinant Proteins (chemistry)
• Sequence Homology, Amino Acid
• Transfection
• Trypanosoma brucei brucei (metabolism)
• Zinc (chemistry)