Cloning, expression, and characterization of sialic acid synthases

The most commonly occurring sialic acid, N-acetylneuraminic acid, is the repeating unit in polysialic acid chain of human neuronal cell adhesion molecule as well as in capsular polysialic acid of neuroinvasive bacteria, Escherichia coli K1 and Neisseria meningitidis. Sialic acid synthesis and polyme...

Full description

Saved in:
Bibliographic Details
Published in:Biochemical and biophysical research communications 2005-12, Vol.338 (3), p.1507-1514
Main Authors: Hao, Jijun, Balagurumoorthy, Pichumani, Sarilla, Suryakala, Sundaramoorthy, Munirathinam
Format: Article
Language:English
Subjects:
Antifreeze protein
Cloning
Cloning, Molecular
Enzyme Stability
Escherichia coli
Expression
Gene Expression - genetics
Humans
Hydrogen-Ion Concentration
Kinetics
Metals, Heavy - pharmacology
Molecular Weight
Mutagenesis
Mutagenesis, Site-Directed
Neisseria meningitidis
Neisseria meningitidis - enzymology
Neisseria meningitidis - genetics
Oxo-Acid-Lyases - chemistry
Oxo-Acid-Lyases - genetics
Oxo-Acid-Lyases - isolation & purification
Oxo-Acid-Lyases - metabolism
Protein Binding
Sialic acid
Steady-state kinetics
Temperature
TIM barrel domain
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The most commonly occurring sialic acid, N-acetylneuraminic acid, is the repeating unit in polysialic acid chain of human neuronal cell adhesion molecule as well as in capsular polysialic acid of neuroinvasive bacteria, Escherichia coli K1 and Neisseria meningitidis. Sialic acid synthesis and polymerization occur in slightly different pathways in animals and bacteria. N-Acetylneuraminic acid (NeuNAc) is synthesized by the condensation of phosphoenolpyruvate and N-acetylmannosamine by NeuNAc synthase in bacteria. The mammalian homologue N-acetylneuraminic acid-9-phosphate (NeuNAc-9-P) synthase uses N-acetylmannosamine-6-phosphate in the condensation reaction to produce NeuNAc-9-P. Both subfamilies of sialic acid synthases possess N-terminal triosephosphate isomerase barrel domain and C-terminal antifreeze protein domain. We report cloning of the genes, expression, purification, and characterization of human NeuNAc-9-P synthase and N. meningitidis NeuNAc synthase. Stability of the purified enzymes and effects of pH and temperature on their activities were evaluated. Enzyme kinetics and preliminary mutagenesis experiments reveal the importance of C-terminal antifreeze protein domain and a conserved cysteine residue for the enzyme activities.
ISSN:0006-291X
1090-2104
DOI:10.1016/j.bbrc.2005.10.113