Soluble polymer-protein conjugates: 1. Reactive N-(sym-trinitroaryl) polyacrylamide/acrylhydrazide copolymers and derived carbonic anhydrase conjugates

Abstract

Two copolymers of acrylamide and N-acryl- N′-t-butoxycarbonyl hydrazine were prepared and some of the t-butoxycarbonyl groups removed by acid hydrolysis to give acyl hydrazide residues pendant on the hydrocarbon backbone. The modified copolymers were dyed by reaction with sodium trinitrobenzene sulphonate and more acyl hydrazide residues generated by removal of the remaining t-butoxycarbonyl groups. The intense red polymers so produced were activated by treatment with nitrous acid and coupled with carbonic anhydrase to give coloured, water soluble enzyme conjugates. Compared to the native carbonic anhydrase the soluble conjugates were more stable to heat denaturation and exhibited much reduced values of K m when p-nitrophenylacetate was used as substrate.