l-Glutamine d-fructose 6-phosphate amidotransferase (EC 2.6.1.16) was extracted and purified 600-fold by acetone fractionation and diethylaminoethyl cellulose column chromatography from mung bean seeds (Phaseolus aureus). The partially purified enzyme was highly specific for l-glutamine as an amide nitrogen donor, and l-asparagine could not replace it. The enzyme showed a pH optimum in the rang...

Two major components of pineapple bromelain, purified to electrophoretical homogeneity, appeared to have the same oligosaccharide group consisting of n-glucosamine, n-mannose, D-xylose, and L-fucose in ratios of 2:2: 1: 1. By exhaustive proteolysis of the bromelains, glycopeptides containing only Asx, Glx, and Ser were obtained. Periodate oxidation, methylation, and glycosidase digestion showed...

The surface glycopeptides of human trophoblastic cells have been compared with those of fetal cells from the same embryos using double-labeling methods with isotopes of L-fucose and D-glucosamine. A faster eluting, neuraminidase-sensitive, fraction was observed on Sephadex chromatography of the trophoblast spectra when D-glucosamine was used as precursor. Labeling with fucose did not appear to ...

BACKGROUND Glucosamine 6-phosphate deaminase from Escherichia coli is an allosteric hexameric enzyme which catalyzes the reversible conversion of D-glucosamine 6-phosphate into D-fructose 6-phosphate and ammonium ion and is activated by N-acetyl-D-glucosamine 6-phosphate. Mechanistically, it belongs to the group of aldoseketose isomerases, but its reaction also accomplishes a simultaneous amina...

background: degenerative joint disease (djd) is the most common joint disease in human beings. previous studies have explained that glucosamine is preferred as placebo and in efficacy compared with nsaid’s in treatment of patients’ knee osteoarthritis. alendronate was used to treat osteoporotic patients and its efficacy was established. objectives: the aim of this study was to compare the effic...