Preparation of protein conjugates

King, P., Li, Y., and Kochoumian, L. (1978) Preparation of protein conjugates via intermolecular disulfide bond formation. Biochemistry 17, 1499. 

Zalipsky, S., Seltzer, R., and Nho, K. (1991) Succinimidyl carbonates of polyethylene glycol Useful reactive polymers for preparation of protein conjugates. In Polymeric Drugs and Drug Delivery Systems (R.L. Dunn, and R.M. Ottenbrite, eds.), pp. 91-100. American Chemical Society, Washington, D.C. 

Originally, for preparation of such conjugates the hydroxyl groups of monomethoxy-PEG (mPEG) were activated with cyanuric chloride, and the resulting compound then coupled with proteins (10). This approach suffers from disadvantages, such as the toxicity of cyanuric chloride and its limited applicability for modification of proteins having essential cysteine or tyrosine residues, as manifested by their loss of activity. 

Dent AH, Aslam M (1999) The preparation of protein-protein conjugates. In Aslam M, Dent AH (eds.) Bioconjugation. Protein coupling techniques for the biomedical sciences. Macmillan Reference Ltd., London,... 

Primary amine groups on proteins consisting of N-terminal a-amines and lysine side-chain e-amines are typically present in abundant quantities for modification or conjugation reactions. Occasionally, however, a protein or peptide will not contain sufficient amounts of available amines to allow for an efficient degree of coupling to another molecule or protein. For instance, horseradish peroxidase (HRP), a popular enzyme to employ in the preparation of antibody conjugates, only possesses two free amines that... 

Figure S.6 Derivatization reagents for the preparation of pyridoxamine conjugates of fatty acid binding proteins.

In 1956 our laboratory, in collaboration with Beiser and Lieberman, became interested in preparing steroid-protein conjugates that were to be used to elicit antisteroid antibodies. An examination of the literature at that time showed that the azo coupling techniques of Landsteiner were still dominant. Like him, we chose to use the serum albumins because they were inexpensive and likely to yield soluble conjugates. However, an examination of the amino acid content of bovine serum albumin (BSA) (Fig. 1) convinced us that substitution by such relatively complex haptens as steriods should be attempted by reaction with the more plentiful c-amino groups of the lysine residues rather than by an azo coupling reaction with tyrosine, tryptophan, and imidazole residues. This meant forma-... 

Figure 3 Representative conjugation methods for the preparation of semisynthetic conjugate vaccines. Protein-carbohydrate conjugation via (a) reductive amination ...

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