title: Optimized polymer-enzyme electrostatic interactions significantly improve penicillin G amidase efficiency in charged PEGA polymers.
abstract: Hydrolytic yields as high as 80% were obtained by using penicillin G amidase (PGA) on substrates anchored on optimized positively charged PEGA polymers. By increasing the amount of permanent charges inside the polymer, electrostatic interactions between the positively charged PEGA(+) and the negatively charged PGA (pI = 5.2-5.4) were strengthened, thus favouring the accessibility of the bulky enzyme (MW = 88 kDa) inside the pores. The effect of different amounts of charges on polymer swelling and protein retention inside the polymer was investigated and correlated to the enzyme efficiency demonstrating that electrostatic interactions predominate over swelling properties in determining enzyme accessibility.
authors.affiliation: Dipartimento di Scienze Farmaceutiche, Università degli Studi, Piazzale Europa 1, 34127 Trieste, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Basso
authors.forename: Beatrice A
authors.initials: BA
authors.lastname: Maltman
authors.forename: Sabine L
authors.initials: SL
authors.lastname: Flitsch
authors.forename: Graham
authors.initials: G
authors.lastname: Margetts
authors.forename: Ian
authors.initials: I
authors.lastname: Brazendale
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ebert
authors.forename: Paolo
authors.initials: P
authors.lastname: Linda
authors.forename: Silvia
authors.initials: S
authors.lastname: Verdelli
authors.forename: Lucia
authors.initials: L
authors.lastname: Gardossi