Kinetic and crystallographic studies of Escherichia coli UDP-N-acetylmuramate:L-alanine ligase

Protein Science : a Publication of the Protein Society
J J EmanueleJ J Villafranca

Abstract

Uridine diphosphate-N-acetylmuramate:L-alanine ligase (EC 6.3.2.8, UNAM:L-Ala ligase or MurC gene product) catalyzes the ATP-dependent ligation of the first amino acid to the sugar moiety of the peptidoglycan precursor. This is an essential step in cell wall biosynthesis for both gram-positive and gram-negative bacteria. Optimal assay conditions for initial velocity studies have been established. Steady-state assays were carried out to determine the effect of various parameters on enzyme activity. Factors studies included: cation specificity, ionic strength, buffer composition and pH. At 37 degrees C and pH 8.0, kcat was equal to 980 +/- 40 min-1, while K(m) values for ATP, UNAM, and L-alanine were, 130 +/- 10, 44 +/- 3, and 48 +/- 6 microM, respectively. Of the metals tested only Mn, Mg, and Co were able to support activity. Sodium chloride, potassium chloride, ammonium chloride, and ammonium sulfate had no effect on activity up to 75 mM levels. The enzyme, in appropriate buffer, was stable enough to be assayed over the pH range of 5.6 to 10.1. pH profiles of Vmax/K(m) for the three substrates and of Vmax were obtained. Crystallization experiments with the enzyme produced two crystal forms. One of these has been characterized ...Continue Reading

Citations

Feb 15, 2002·Bioorganic & Medicinal Chemistry Letters·Mui Mui SimSue Kim Lee
Dec 21, 2002·Molecular Microbiology·Ahmed El ZoeibyRoger C Levesque
Aug 21, 2015·Proceedings of the National Academy of Sciences of the United States of America·Mathanraj PackiamAnthony T Maurelli
Feb 13, 2008·FEMS Microbiology Reviews·Hélène BarreteauDidier Blanot
Aug 29, 2006·Journal of Molecular Biology·Clyde A Smith
Mar 21, 2002·Expert Opinion on Therapeutic Targets·David W Green
May 4, 2011·Chembiochem : a European Journal of Chemical Biology·Saskia RauschRoderich D Süssmuth
Nov 26, 2010·Critical Reviews in Biotechnology·Ankur GautamRupinder Tewari
Nov 19, 2020·Pharmaceuticals·Fausto QuedaM Manuel B Marques
Dec 11, 1999·Biochimica Et Biophysica Acta·E Breukink, B de Kruijff
Feb 13, 2007·Bioorganic & Medicinal Chemistry·Yves L Janin
Jul 19, 2001·Journal of the American Chemical Society·M S VanNieuwenhzeL C Blaszczak

❮ Previous
Next ❯

Related Concepts

Related Feeds

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.

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.