Glucosamine Research Today is a free monthly online journal that collates and summarizes the latest research about Glucosamine, including details on chondroitin sulfate, uses, effects, benefits, arthritis.

Crystallization and preliminary X-ray analysis of a family 19 glycosyl hydrolase from Carica papaya latex.

Huet J, Azarkan M, Looze Y, Villeret V, Wintjens R

Laboratoire de Chimie Générale (CP 206/4), Institut de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, B-1050 Bruxelles, Belgium. jhuet@ulb.ac.be

A chitinase isolated from the latex of the tropical species Carica papaya has been purified to homogeneity and crystallized. This enzyme belongs to glycosyl hydrolase family 19 and exhibits exceptional resistance to proteolysis. The initially observed crystals, which diffracted to a resolution of 2.0 A, were improved through modification of the crystallization protocol. Well ordered crystals were subsequently obtained using N-acetyl-D-glucosamine, the monomer resulting from the hydrolysis of chitin, as an additive to the crystallization solution. Here, the characterization of a chitinase crystal that belongs to the monoclinic space group P2(1), with unit-cell parameters a = 69.08, b = 44.79, c = 76.73 A, beta = 95.33 degrees and two molecules per asymmetric unit, is reported. Diffraction data were collected to a resolution of 1.8 A. Structure refinement is currently in progress.

Published 5 May 2008 in Acta Crystallogr Sect F Struct Biol Cryst Commun, 64: 371-4.
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Articles on Glucosamine published 2 May 2008:

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Infrared spectra of solid and aqueous solutions of N-acetyl-alpha-d-glucosamine and beta-d-glucuronic acid have been investigated by means of Fourier transform infrared (FT-IR) spectroscopy and quantum chemical density functional theory (DFT) calculations. The errors of the computed harmonic force field were corrected according to the scaled quantum mechanical (SQM) method of Pulay, with scale factors partly from the literature and partly developed here. Scale factors for the hydrogen-bonded OH ... [Abstract] [Full-text]

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