The capsule polysaccharide of Neisseria meningitidis serogroup B is composed of a homopolymer of alpha-2-->8 linked N-acetyl-neuraminic acid (sialic acid). The enzymes required for sialic acid biosynthesis and polymerization are encoded in region A of the capsule gene complex. We here describe the enzymatic activity of the siaA gene product as determined by biochemical analysis. siaA was overex...

Kitin adalah homopolimer yang tersusun dari N-acetyl d-glucosamine dan glucosamine terikat dengan β 1–4 glycosidic . umumnya diperoleh ekstraksi kulit udang melalui proses deproteinasi demineralisasi tahapan lama panjang. Pada penelitian ini dilakukan isolasi kitin jamur tiram sebagai alternatif sumber bahan baku bantuan reaktor microwave Proses pada variasi waktu antara 5-60 menit untuk memper...

The glycosyl hydrolase 18 (GH18) family consists of active chitinases as well as chitinase like lectins/proteins (CLPs). The CLPs share significant sequence and structural similarities with active chitinases, however, do not display chitinase activity. Some of these proteins are reported to have specific functions and carbohydrate binding property. In the present study, we report a novel chitin...

We describe the design and synthesis of substrate and internal standard conjugates for application in profiling enzyme activity of the enzymes alpha-D-2-deoxy-2-N-sulfonamido-glucosamine sulfamidase, alpha-D-2-deoxy-2-N-acetyl-glucosamine hydrolase, acetyl-coenzymeA:alpha-D-2-deoxy-2-amino-glucosamine transferase, and alpha-D-2-deoxy-2-N-acetyl-glucosamine-6-sulfate sulfatase. Deficiency of any...

Studies with extracts obtained from mung beans (Phaseolus aureus) showed that UDP-N-acetyl d-glucosamine is formed from d-fructose 6-phosphate by a series of the following enzymic reactions: [Formula: see text]UDP-N-acetyl-d-glucosamine inhibits the first reaction in the multistep pathway leading to its biosynthesis.

Glucosamine/glucosaminide N-acetyltransferase or GlmA catalyzes the transfer of an acetyl group from acetyl CoA to the primary amino group of glucosamine. The enzyme from Clostridium acetobutylicum is thought to be involved in cell wall rescue. In addition to glucosamine, GlmA has been shown to function on di- and trisaccharides of glucosamine as well. Here we present a structural and kinetic a...

One of the few naturally occurring acetyl derivatives in the animal body is that of glucosamine. It is well known that glucosamine is present in a large number of polysaccharides in many organisms and almost always is present there in acetylated form. During studies in this laboratory on the acetylation reaction, we, therefore, became interested in the possibility of carrying out an enzymatic a...

Very potent inhibitors were synthesized for the enzymatic deacetylation of N-acetyl-d-glucosamine-6-phosphate (NagA) and N-acetyl-d-glutamate (DGD). The methyl phosphonamidate derivative of d-glucosamine-6-phosphate bound to N-acetyl-d-glucosamine-6-phosphate deacetylase with an equilibrium dissociation constant of 34 +/- 5 nM at pH 7.5 and an association rate constant of 6.1 x 103 M-1 s-1. The...

The effects of hexosamines and their acetyl derivatives on the aggregation of 4-dimethylaminoazobenzene-induced rat hepatoma cells, dRLa-74 and dRLh-84, which have a low and high tumor-producing activity, respectively, were examined in rotation-mediated cell culture. D-Glucosamine, D-galactosamine, and D-mannosamine had relatively little effect on aggregation of either strain of hepatoma cells ...