Amino acids yields during proteolysis catalyzed by carboxypeptidase A are strongly dependent on substrate pre-hydrolysis

Producing a phenylalanine-free pool of peptides after tailored enzymatic hydrolyses of cheese whey

“…In Pinto et al (2008) it was observed that pre-hydrolyses with trypsin and chymotrypsin directly influences the yields of the Cterminal amino acids released by CPA. However, the sequentialhydrolyses strategy was not optimized for releasing Phe residues.…”

“…Hence, estimation of substrate-specific kinetic parameters is not possible, due to the large number of different peptide bonds that are cleaved by the enzyme (Márquez and Vázquez, 1999). Instead, substrates are lumped into single pseudo-component -hydrolysable bondsand, consequently, reaction products are lumped into hydrolyzed bonds (Adler-Nissen, 1986;Tardioli et al, 2005;Pinto et al, 2008). Barros and Malcata (2002) also applied a lumping approach for the kinetics of whey protein hydrolysis by immobilized cardosins A and B.…”

“…In Pinto et al (2008), the kinetic model developed provided accurate predictions of the amino acids concentrations at different times using this exopeptidase. The correct inference of Phe contents is mandatory when producing formulations for phenylketonuria patients.…”

“…The sequential hydrolyses of cheese whey proteins using trypsin, chymotrypsin and carboxypeptidase A (CPA) may produce hydrolysates with low Phe contents (Tardioli et al, 2003;Pinto et al, 2008). This work demonstrates how the first two pre-hydrolyses affect the yield of Phe by CPA: cheese whey proteins were sequentially hydrolyzed with trypsin and chymotrypsin, both immobilized on glyoxyl-agarose gel particles, at different enzyme/substrate ratios and up to different degrees of hydrolysis.…”

“…Pinto et al (2008) presented a kinetic model for hydrolysis using CPA. In this work, a kinetic study of the remaining hydrolytic step, i.e., the pre-hydrolysis with chymotrypsin, is endeavored.…”