Print Friendly View
Endo-beta-Galactosidase

Catalog Number: 151031, 190445
Endo-beta-Galactosidase


Synonym: Keratan sulfate 1,4-b-D-galactanohydrolase

Source: Escherichia freundii

Description: Endo-b-galactosidase, found in the culture fluid of a strain of Escherichia Freundii 1-5, hydrolyzes specifically the b-galactosidic linkages of non-sulfated galactosyl residues in keratan sulfates 6 and various substrates 7 such as glycoproteins 8,9 , milk oligosaccharides 6 and glycosphingolipids 10 having the following structure.

. . . . ----> GlcNAcb1 ---> 3Galb1---^---> 4Gle (or GlcNAc) ---> . . . .
Endo-b-galactosidase

This enzyme is suitable for studies of precise structures of various glycoconjuagates. Furthermore, the enzyme is expected to be useful to study the functions and structures of cell surface substances 11-13 , since it can directly act on the intact cell surface.

Physical Description: Lyophilized powder

Contaminants: Notice that this enzyme preparation contains a trace (less than 2.5 mmole) of potassium phosphate buffer, pH 7.0.

The enzyme preparation has no detectable activity of the following enzymes.
1. ProteaseAccording to Kunitz 14
2. Glycosidasea-L-Fucosidase, a- and b-D-Galactosidase, a- and b-D-Glucosidase, a- and b-N-Acetylgalactosaminidase, a- and b-N-Acetylglucosaminidase, a- and b-Mannosidase, b-Xylosidase, Neuraminidase
3. ChondroitinaseDetermination of HexNAc at reducing end 15
4. HeparinaseDetermination of A232 16
5. HeparitinaseSame as above
Optimum pH ........................ 5-6
Recommended reaction temperature ... 50oC

Unite Definition: One unit of the enzyme is that amount required to hydrolyze b-galactosidic linkage of KS-1 (keratan sulfate from bovine cornea) to liberate reducing group correspond to 1 mmole of galatose per minute at 37oC, pH 5.8. Protein is determined according to Lowry as BSA 17.

Method: Standard reaction mixture contains KS-1 (0.2 mmole as galactose), 10mmole sodium acetate buffer, pH 5.8, and enzyme in a total volume of 0.2 ml.
After incubation at 37oC for 10 to 30 minutes, reducing sugars (as galactose) are determined according to Park-Johnson 18.

Storage: Stable for 2 years when stored at -20oC. Dissolved enzyme is also stable for a month when stored at -20oC. However, repeated freezing and thawing may decrease the enzyme

References:
  1. Kitamikado,M., Ueno,R. and Nakamura,T. Bull.Jap.Soc.Sci.Fish. 36, 592 (1970)
  2. Kitamikado,M., Ueno,R. and Nakamura,T. Bull.Jap.Soc.Sci.Fish. 36, 1172 (1970)
  3. Kitamikado,M. and Ueno,R. Bull.Jap.Soc.Sci.Fish. 36, 1175 (1970)
  4. Kitamikado,M. and Ueno,R. Bull.Jap.Soc.Sci.Fish. 38, 497 (1972)
  5. Ueno,R. and Kitamikado,M. Bull.Jap.Soc.Sci.Fish. 38, 503 (1972)
  6. Fukuda,M.N. and Matsumura,G. Biochem. Biophys.Res.Commun. 64, 465 (1975)
  7. Kitamikado,M Protein,Nucleic Acid and Enzyme 29, 386 (1984)
  8. Fukuda,M.N. and Matsumura,G. J.Biol.Chem. 251, 6218 (1976)
  9. Tsay,G.C., Dawson,G. and Li,Y-T. Biochem.Biophys.Acta 385, 305 (1975)
  10. Fukuda,M.N., Watanabe,K. and Hakomori,S. J.Biol.Chem. 253, 6812 (1978)
  11. Fukuda,M., Fukada,M.N. and Hakomori,S. J.Biol.Chem. 254, 3700 (1979)
  12. Fukada,M.N. Fukuda,M. and Hakomori,S. J..Biol.Chem. 254, 5458 (1979)
  13. Fukuda,M. Seikagaku 52, 244 (1980)
  14. Kunitz,M. J.Gen.Physiol. 30, 291 (1947)
  15. Strominger,J.L., Park,J.T. and Thompson,R.E. J.Biol.Chem. 234, 3262 (1959)
  16. Linker,A. and Hovingh,P. Methods in Enzymol. 28, 902 (1972)
  17. Lowry,O.H., Rosebrough,N.J., Farr,A.L. and Randall,R.J. J.Biol.Chem. 193, 265 (1951)
  18. Park,J.T. and Johnson,M.J. J.Biol.Chem. 181, 149 (1949)