Entrapment of Nonproteolytic Enzymes in α2-Macroglobulin Using Immobilized Trypsin

✍ Scribed by M. Mirza; M. Saleemuddin

• Book ID: 102966413
• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 574 KB
• Volume: 213
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1006/abio.1993.1396

✦ Synopsis

Entrapment in human (\alpha_{2})-macroglobulin ( (\alpha_{2} M) ) of nonproteolytic enzymes was achieved with the help of trypsin covalently attached to the Sepharose matrix. While it was also possible to achieve entrapment by the exposure of the (\alpha_{2}) M: enzyme mixtures to soluble trypsin, use of the immobilized proteinase resulted in improved entrapment yields and also prevented the coentrapment of trypsin. Both soluble and immobilized trypsin transformed (\alpha_{2} M) to the electrophoretically fast form but the immobilized trypsin required relatively longer incubation to bring about the transformation. Horseradish peroxidase was entrapped in higher yield in (\alpha_{2} M) compared to the relatively high-molecular-weight invertase. (\alpha_{2}) M-entrapped peroxidase and invertase appeared highly accessible to their respective substrates, as evident from their relatively unaltered (K_{m}) values. (\alpha_{2} \mathrm{M})-associated invertase, in spite of its large dimensions, failed to crossreact with the rabbit anti-invertase antiserum, indicating its physical entrapment rather than any other form of association. (o 1993 Academic Press, Inc.