Article

Glycation is a condensation reaction between reducing sugars and primary amino groups in proteins. It starts with formation of Schiff bases and Amadori products (called early glycation products), which are later converted into complex heterocyclic compounds designated as advanced glycation end (AGE) products. Until recently glycation was studied mainly in higher eukaryotes and only our recent studies [6] showed that glycation took place also bacteria. The aim of this study is to investigate the effect of growth media and nutrient broth ingredients on glycation of proteins in Escherichia coli. The obtained results indicate that glycation is more extensive in rich media and depends on the type and source of nutrient broth ingredients (yeast extract and protein hydrolysate). Sometimes different batches of one ingredient produced by the same manufacturer might have different effect on glycation. Since the increased glycation decreases stability and biological activity of recombinant proteins, we highly recommend all nutrient broth ingredients to be tested for their effect on glycation before use for manufacturing of such proteins.