Jan 16, 1996

Acetyltransfer precedes uridylyltransfer in the formation of UDP-N-acetylglucosamine in separable active sites of the bifunctional GlmU protein of Escherichia coli

Biochemistry
A M GehringEric D Brown

Abstract

The GlmU protein is a bifunctional enzyme with both acetyltransferase and uridylyltransferase (pyrophosphorylase) activities which catalyzes the transformation of glucosamine-1-P, UTP, and acetyl-CoA to UDP-N-acetylglucosamine [Mengin-Lecreulx, D., & van Heijenoort, J. (1994) J. Bacteriol. 176, 5788-5795], a fundamental precursor in bacterial peptidoglycan biosynthesis and the source of activated N-acetylglucosamine in lipopolysaccharide biosynthesis in Gram-negative bacteria. In the work described here, the GlmU protein and truncation variants of GlmU (N- and C-terminal) were purified and kinetically characterized for substrate specificity and reaction order. It was determined that the GlmU protein first catalyzed acetyltransfer followed by uridylyltransfer. The N-terminal portion of the enzyme was capable of only uridylyltransfer, and the C-terminus catalyzed only acetyltransfer. GlmU demonstrated a 12-fold kinetic preference (kcat/Km, 3.1 x 10(5) versus 2.5 x 10(4) L.mol-1.s-1) for acetyltransfer from acetyl-CoA to glucosamine-1-P as compared to UDP-glucosamine. No detectable uridylyltransfer from UTP to glucosamine-1-P was observed in the presence of GlmU; however, the enzyme was competent in catalyzing the formation of UDP...Continue Reading

  • References
  • Citations51

References

  • We're still populating references for this paper, please check back later.
  • References
  • Citations51

Mentioned in this Paper

Alkalescens-Dispar Group
Carboxy-Terminal Amino Acid
Lipopolysaccharide Biosynthesis Pathway
Acetyl Coenzyme A
Mucopolysaccharidosis III
Gram-Negative Bacteria
Glucosamine
Acyltransferase
Peptide Fragments
Compound A 12

Related Feeds

Bacterial Cell Wall Structure

Bacterial cell walls are made of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids. Here is the latest research on bacterial cell wall structures.

BioHub - Researcher Network

The Chan-Zuckerberg Biohub aims to support the fundamental research and develop the technologies that will enable physicians to cure, prevent, or manage all diseases in our childrens' lifetimes. The CZ Biohub brings together researchers from UC Berkeley, Stanford, and UCSF. Find the latest research from the CZ Biohub researcher network here.

Bacterial Cell Wall Structure (ASM)

Bacterial cell walls are made of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids. Here is the latest research on bacterial cell wall structures.