Covalent cross-linking of proteins without chemical reagents |
| |
Authors: | Simons Brigitte L King Mary C Cyr Terry Hefford Mary Alice Kaplan Harvey |
| |
Affiliation: | Centre for Biologics Research, Biologics and Genetic Therapies Directorate, Health Canada, Ottawa, Canada K1A 0L2. |
| |
Abstract: | A facile method for the formation of zero-length covalent cross-links between protein molecules in the lyophilized state without the use of chemical reagents has been developed. The cross-linking process is performed by simply sealing lyophilized protein under vacuum in a glass vessel and heating at 85 degrees C for 24 h. Under these conditions, approximately one-third of the total protein present becomes cross-linked, and dimer is the major product. Chemical and mass spectroscopic evidence obtained shows that zero-length cross-links are formed as a result of the condensation of interacting ammonium and carboxylate groups to form amide bonds between adjacent molecules. For the protein examined in the most detail, RNase A, the cross-linked dimer has only one amide cross-link and retains the enzymatic activity of the monomer. The in vacuo cross-linking procedure appears to be general in its applicability because five different proteins tested gave substantial cross-linking, and co-lyophilization of lysozyme and RNase A also gave a heterogeneous covalently cross-linked dimer. |
| |
Keywords: | Protein cross-linking lyophilized protein zero-length cross-linking covalent cross-linking in vacuo modification |
本文献已被 PubMed 等数据库收录! |
|