title: Effect of pH and recombinant barley (Hordeum vulgare L.) endoprotease B2 on degradation of proteins in soaked barley.
abstract: Nonfermented soaking of barley feedstuff has been established as an in vitro procedure prior to the feeding of pigs as it can increase protein digestibility. In the current study, two feed cultivars of barley (Finlissa and Zephyr) were soaked in vitro either nonbuffered or buffered at pH 3.6 and 4.3. Solubilized and degraded proteins evaluated by biuret, SDS-PAGE, and differential proteomics revealed that pH 4.3 had the greatest impact on both solubilization and degradation. In order to boost proteolysis, the recombinant barley endoprotease B2 (rec-HvEP-B2) was included after 8 h using the pH 4.3 regime. Proteolysis evaluated by SDS-PAGE and differential proteomics confirmed a powerful effect of adding rec-HvEP-B2 to the soaked barley, regardless of the genotype. Our study addresses the use of rec-HvEP-B2 as an effective feed enzyme protease. HvEP-B2 has the potential to increase the digestibility of protein in the pig, either supplied as recombinant additive or as possible new selection criterion in barley breeding.
authors.affiliation: Aarhus University , Research Center Foulum, Department of Animal Science, DK-8830 Tjele, Denmark.
authors.forename: Jesper Bjerg
authors.initials: JB
authors.lastname: Christensen
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Dionisio
authors.forename: Hanne Damgaard
authors.initials: HD
authors.lastname: Poulsen
authors.forename: Henrik
authors.initials: H
authors.lastname: Brinch-Pedersen
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D004063:Digestion; D010450:Endopeptidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005503:Food Additives / Q000737:chemistry / Q000378:metabolism; D001467:Hordeum / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013552:Swine
chemical_list: D005503:Food Additives; D010940:Plant Proteins; D010450:Endopeptidases