Background
Type: Article

Enhancement of Tryptic Digestibility of Milk β-Lactoglobulin Through Treatment with Recombinant Rice Glutathione/Thioredoxin and NADPH Thioredoxin Reductase/Thioredoxin Systems

Journal: Applied Biochemistry and Biotechnology (02732289)Year: 2019/02/15Volume: 187Issue: 2Pages: 649 - 661
DOI:10.1007/s12010-018-2793-4Language: English

Abstract

β-Lactoglobulin (BLG), a member of lipocalin family, is one of the major bovine milk allergens. This protein exists as a dimer of two identical subunits and contains two intramolecular disulfide bonds that are responsible for its resistance to trypsin digestion and allergenicity. This study aimed to evaluate the effect of reduction of disulfide bonds of BLG with different rice thioredoxins (Trxs) on its digestibility and allergenicity. Therefore, the active recombinant forms of three rice Trx isoforms (OsTrx1, OsTrx20, and OsTrx23) and one rice NADPH-dependent Trx reductase isoform (OsNTRB) were expressed in Escherichia coli. Based on SDS-PAGE, HPLC analysis, and competitive ELISA, the reduction of disulfide bonds of BLG with OsNTRB/OsTrx23, OsNTRB/OsTrx1, GSH/OsTrx1, or GSH/OsTrx20 increased its trypsin digestibility and reduced its immunoreactivity. The finding of this study opens new insights for application of plant Trxs in the improvement of food protein digestibility. Especially, the use of OsTrx20 and OsTrx1 are more cost-effective than E. coli and animal Trxs due to their reduction by GSH and no need to NADPH and Trx reductase as mediator enzyme. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.


Author Keywords

AllergenicityDigestibilityGlutathioneMilkNADPH-dependent thioredoxin reductaseThioredoxinβ-LactoglobulinEscherichia coliGlutathioneLactoglobulinsOryzaPlant ProteinsRecombinant ProteinsThioredoxin-Disulfide ReductaseThioredoxins

Other Keywords

Escherichia coliGlutathioneLactoglobulinsOryzaPlant ProteinsRecombinant ProteinsThioredoxin-Disulfide ReductaseThioredoxinsAllergensCost effectivenessCovalent bondsPeptidesSulfur compoundsbeta lactoglobulinostrx1 proteinostrx20 proteinostrx23 proteinreduced nicotinamide adenine dinucleotide phosphatethioredoxinthioredoxin reductaseunclassified druglactoglobulinplant proteinrecombinant proteinAllergenicityDigestibilityGlutathionesMilkArticlecost effectiveness analysisdigestiondisulfide bondenzyme linked immunosorbent assayhigh performance liquid chromatographyimmunoreactivitynonhumanpolyacrylamide gel electrophoresisprotein expressionprotein intakechemistryenzymologygeneticsmetabolismReduction