Recent reports from this laboratory (2-4) and other laboratories (5, 6) have elucidated the pathway of biosynthesis of N-acetylneuraminic acid from N-acetyl-n-mannosamine and phosphoenolpyruvic acid in mammalian systems. The over-all biosynthetic reaction for rat liver and bovine submaxillary gland is catalyzed by 3 enzymes: a kinase, a condensing enzyme, and a dephosphorylating enzyme. N-Acety...

This article reports on experimental evidence that an Escherichia coli nanR mutant shows inhibited growth in N-acetylneuraminic acid. This effect is prevented when inocula are grown in an excess of glucose, but not in an excess of glycerol. The nanATEK operon is controlled by catabolite repression, suggesting that diminished expression of the nanATEK operon in the presence of glucose explains t...

Objective(s) Some properties of neuraminidase produced by Pseudomonas aeruginosa PAO1 growth in a defined medium (BHI) were examined and evaluated for its features. Materials and Methods The obtained supernatant enzyme of P. aeruginosa PAO1 cultures was used in a sensitive fluorometric assay by using 2'-(4-methylumbelliferyl) a-D-N acetylneuraminic acid as substrate. As hydrolyzing MUN with ...

The original version of this article contained an error in testing the kinetic parameters of CgNal towards pyruvate, in which the concentration of ManNAc (50 mM) was not in excess. This error was corrected by re-running the assay in the presence of excessive ManNAc (180 mM). The corrected kinetic parameters of CgNal towards pyruvate are shown in Table 1. These changes do not change the conclusi...

N-Acetylneuraminate lyase [N-acetylneuraminic acid aldolase EC 4.1.3.3] from Escherichia coli was purified by protamine sulfate treatment, fractionation with ammonium sulfate, column chromatography on DEAE-Sephacel, gel filtration on Ultrogel AcA 44, and preparative polyacrylamide gel electrophoresis. The purified enzyme preparation was homogeneous on analytical polyacrylamide gel electrophores...

N-Acetylneuraminic acid lyase (NAL, E.C. number 4.1.3.3) is a Class I aldolase that catalyzes the reversible aldol cleavage of N-acetylneuraminic acid (Neu5Ac) from pyruvate and N-acetyl-D-mannosamine (ManNAc). Due to the equilibrium favoring Neu5Ac cleavage, the enzyme catalyzes the rate-limiting step of two biocatalytic reactions producing Neu5Ac in industry. We report the biochemical charact...