The efficiency of different coupling procedures for the linkage of oestriol-16α-glucuronide, oestrone-3-glucuronide and pregnanediol-3α-glucuronide to four different enzymes

• Published in: Journal of steroid biochemistry Vol. 14; no. 9; pp. 861 - 866
• Main Authors: Rajkowski, K.M., Cittanova, N.
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.09.1981
• Subjects: Alcohol Oxidoreductases - metabolism; Anhydrides; Chemical Phenomena; Chemistry; Estriol - analogs & derivatives; Estrogens, Conjugated (USP); Estrone - analogs & derivatives; Glucosephosphate Dehydrogenase - metabolism; Glucuronates; Horseradish Peroxidase - metabolism; Immunoenzyme Techniques; Pregnanediol - analogs & derivatives; Urease - metabolism
• ISSN: 0022-4731
• DOI: 10.1016/0022-4731(81)90234-X

The coupling of oestrone-3-glucuronide, oestriol-16α-glucuronide and pregnanediol-3α-glucuronide with alcohol dehydrogenase, glucose-6-phosphate dehydrogenase, urease (two preparations) and horseradish peroxidase has been investigated. Two carbodiimide methods, the hydroxysuccinimide/dicyclo-hexylcarbodiimide method and the mixed anhydride method for coupling were tested. Only the mixed anhydride method was found suitable and high recoveries of the enzymes were obtained. Though alcohol dehydrogenase and glucose-6-phosphate dehydrogenase sustained heavy losses of specific activity, horseradish peroxidase and urease were less affected by coupling, the latter even appeared to be activated. Removal of buffer salts and lyophilization of the products caused losses of enzyme activity but ways of avoiding this are suggested.