Investigating the Impact of Polymer Length, Attachment Site, and Charge on Enzymatic Activity and Stability of Cellulase.

The thermophilic cellulase Cel5a from (Cel5a) was conjugated with neutral, cationic, and anionic polymers of increasing molecular weights. The enzymatic activity toward an anionic soluble cellulose derivative, thermal stability, and functional chemical stability of these bioconjugates were investigated. The results suggest that increasing polymer chain length for polymers compatible with the substrate enhances the positive impact of polymer conjugation on enzymatic activity.

Hydrolytically Stable Maleimide-End-Functionalized Polymers for Site-Specific Protein Conjugation.

Site-specific conjugation to cysteines of proteins often uses ester groups to link maleimide or alkene groups to polymers. However, the ester group is susceptible to hydrolysis, potentially losing the benefits gained through bioconjugation. Here, we present a simple conjugation strategy that utilizes the amide bond stability of traditional 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide coupling while introducing site specificity.