Presence of an endo-beta-galactosidase degrading the linkage region between the chondroitin sulfate chain and core peptide of proteoglycan.
Pyridylamino chondroitin sulfate, of which the reducing terminal xylose was coupled with a fluorescent 2-aminopyridine, was incubated at pH 4.0 with an extract from the mid-gut gland of Patnopecten. The high- and low-molecular-weight products were separated by ethanol precipitation, and identified by high-performance liquid chromatography analysis. The enzyme was found to expose a galactose residue at the reducing terminus of chondroitin sulfate, and also released the pyridylamino disaccharide, galactosylxylose, from the reducing terminal site of pyridylamino chondroitin sulfate. These results suggest that endo-beta-galactosidase activity, which hydrolyzes the galactosylgalactose linkage of peptidochondroitin sulfate, is present in the mid-gut gland of Patnopecten.
Takagaki
K
K
Department of Biochemistry, Hirosaki University School of Medicine, Japan.
Kon
A
A
Kawasaki
H
H
Nakamura
T
T
Tamura
S
S
Endo
M
M
D000631:Aminopyridines; D000818:Animals; D002807:Chondroitin / Q000031:analogs & derivatives*; D002809:Chondroitin Sulfates / Q000378:metabolism*; D005456:Fluorescent Dyes; D005696:Galactosidases / Q000378:metabolism*; D008974:Mollusca / Q000201:enzymology*; D011509:Proteoglycans / Q000378:metabolism*; D001616:beta-Galactosidase / Q000378:metabolism*
D000631:Aminopyridines; D005456:Fluorescent Dyes; D011509:Proteoglycans; D002807:Chondroitin; D002809:Chondroitin Sulfates; D005696:Galactosidases; D001616:beta-Galactosidase