PLASMA METHYLUMBELLIFERYL-TETRA-N-ACETYL-CHITOTETRAOSIDE HYDROLASE - FURTHER STUDY OF ITS CHARACTERISTICS AS A CHITINASE AND COMPARISON WITH ITS ACTIVITY ON REMAZOL-BRILLIANT-VIOLET CARBOXYMETHYL CHITIN

Citation
Wr. Dentandt et S. Scharpe, PLASMA METHYLUMBELLIFERYL-TETRA-N-ACETYL-CHITOTETRAOSIDE HYDROLASE - FURTHER STUDY OF ITS CHARACTERISTICS AS A CHITINASE AND COMPARISON WITH ITS ACTIVITY ON REMAZOL-BRILLIANT-VIOLET CARBOXYMETHYL CHITIN, Clinica chimica acta, 268(1-2), 1997, pp. 107-120
Citations number
22
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Medical Laboratory Technology",Biology
Journal title
ISSN journal
0009-8981
Volume
268
Issue
1-2
Year of publication
1997
Pages
107 - 120
Database
ISI
SICI code
0009-8981(1997)268:1-2<107:PMH-F>2.0.ZU;2-Q
Abstract
We have further studied some characteristics of human plasma specific chitinase by making use of the fluorescent substrate umbelliferyl-tetr a-N-acetyl-beta-D-chitotetraoside (MU-TACT). The enzyme is also active towards the substrates MU-di-N-acetyl-beta-D-chitobioside (MU-DACB) a nd MU-N-acetyl-chitotrioside (MU-TRACT). MU-TACT hydrolase in plasma i s very stable. It is inhibited by the substrate and the product of the reaction and by allosamidin and ethyl-eneglycolchitin. When the activ ity of plasma MU-TACT hydrolase was compared to Remazol Brilliant Viol et carboxymethyl (REV) chitin hydrolase (REV chitinase), it appeared t hat another enzyme -lysozyme - is also active on REV chitin and this e nzyme represents about 50-60% of the total REV chitinase activity. Hig hly increased activity of plasma MU-TACT hydrolase in plasma of Gauche r patients was reflected in a similar increase of REV chitin hydrolase . In these patients, both MU-TACT hydrolase and REV chitinase are tota lly inhibited by allosamidin indicating that specific chitinase is the increased enzyme. With the MU-TACT substrate, specific chitinase is m easured and with REV chitin as substrate the measured activity is a co mbination of specific chitinase (activity inhibited by allosamidin) as well as lysozyme (residual activity after allosamidin inhibition). Fo r measurement of specific chitinase in human plasma and clinical appli cations, the di-, tri- or tetra-N-acetylglucosamine derivatives of MU are recommended. In order to avoid confusion, recommended names are ei ther the total substrate followed by -ase, or chitinase. (C) 1997 Else vier Science B.V.