Some Properties of a Macromolecular Conjugate of Lysozyme Prepared by Modification with a Monomethoxypolyethylene Glycol Derivative

Coupling Reaction and Properties of Poly(ethylene glycol)-linked Phospholipases A2

“…13) In agreement with theseˆndings, the results of this work show that a partial dissociation of the catalytic and in‰ammatory activities of secretory PLA2s could be attained by the covalent modiˆ-cation with PEG. Thus, it was observed that the covalent attachment of PEG to PLA2s has an important eŠect on the enzymatic activity with almost any eŠect on the in‰ammatory response that is produced by B. neuwiedii (Group II) and bee venom (Group III) enzymes.…”

“…Surface lysine residues had been shown to have an important role in the catalytic activity of several 14-kDa PLA 2 s. 13,27,28) As the reaction with PEG involves the covalent attachment of the polymer to amino groups, it was very surprising that the PEG conjugates retained enzymatic activity. For cobra PLA2 the involvement of Lys-6 and Lys-79 in the inhibitory eŠects of manoalide has been clearly established.…”

“…In agreement with this hypothesis, it has been recently suggested that the interaction of ethylene oxide units of PEG with water molecules might be involved in the stabilization of lysozyme. 13) Venom PLA2s have been shown to be highly immunogenic. 29) In fact, one of the major allergens of bee venom is PLA2.…”

“…12) It has been also shown that covalent attachment of PEG to amino groups of proteins increases the thermostability of enzymes. 13) The distribution of the surface lysines of 14-kDa secretory PLA2s is very important for their enzymatic activity. 14) We have shown that the reaction of manoalide, a potent inhibitor of phospholipases, with two speciˆc Lys residues of cobra venom PLA2 accounts for all of its inhibitory activity.…”

Interactions of a Lysozyme-Monomethoxypolyethylene Glycol Conjugate with Lipopolysaccharides and Lipid Bilayers and Effects of Conjugate on Gram-negative Bacteria

“…Most of the derivatives of mPEG developed for coupling with proteins are designed to attach covalently to amino groups in proteins. [8][9][10][11] Several reports suggest that derivatives of mPEG are useful for reduction of the immunogenicity of proteins 8,9,12,13) or preparation of enzymes that catalyze reactions in organic solvents. 10) Several examples of the use of derivatives of mPEG for the stabilization of proteins have been suggested.…”