Succinic anhydride protein modification with

It is now evident that acylation with anhydrides (such as acetic and succinic anhydrides) and with lactones (such as -propiolactone) is being proposed (< ) for improving the solubility of soy protein isolates at acidic pH, particularly for the preparation of coffee whiteners. Moreover, this chemical modification has been evaluated for altering the food-use properties of several milk proteins (40), egg protein (41), wheat protein (42), fish protein (43), and single-cell protein (44). 

Quinqueginsin, a homodimeric protein (Mr 53 kDa) with inhibitory activity against human immunodeficiency virus (HIV), fungi, ribonuclease, and cell-free translation. Quinqueginsin has been isolated from the roots of American ginseng Panax quinquefolium. The inhibitory action towards HIV-1 reverse transcriptase was potentiated after chemical modification with succinic anhydride [H. X. Wang, T. B. Ng, Biochem. Biophys. Res. Commun. 2000, 269, 203]. 

Grant, D.R. The modification of wheat flour proteins with succinic anhydride. Cereal Chem. 50 417 (1973)... 

The mechanisms of modification are different and depend on the chemical molecules used for the reactions. The anhydride of succinic acid reacts with lysine residues, a-amino groups of proteins and free thiol groups. During succinylation, proteins lose their globular structure and undergo aggregation by disulfide cross-binding with other whey proteins. Acetyl anhydride can modify tyrosine residues. 

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