The structures of the native Saccharomyces cerevisiae proteinase A have been solved by molecular replacement in the monoclinic and trigonal crystal forms and refined at 2.6-2.7A resolution. These structures agree overall with those of other uninhibited aspartic proteinases. However, an unusual orientation for the side chain of Tyr75, a conserved residue on the flexible "flap" that covers the ac...

The objective of this research was to determine the effect of the use of rennet substitute on composition and yield of Minas Padrão cheese. Pasteurized and standardized milk (3.0% fat) was divided into 2 parts and prepared for each treatment varying the rennet: batch 1(BOV), commercial calf rennet (Chymosin and pepsin) and batch 2 (QPF), commercial rennet substitute Chy-max (Chymosin) and conve...

The use of agroindustrial wastes not only decreases bioprocesses and disposal costs but also contributes to the upgrading of the residues. An active recombinant methanol-inducible bovine chymosin has been expressed in our laboratory in the yeastKomagataella pastoris, and grape pomace extracts (GRE) were proposed as a convenient C-energy source for the biomass production of the genetically engin...

The effect of age on the enzyme potentialities of abomasum (chymosin and pepsin) and pancreas (chymotrypsin, trypsin, lipase, colipase and amylase) was studied in the preruminant calf. Three foetuses were collected after slaughter of their dams (260 d of gestation) and 32 calves were maintained as preruminant and slaughtered between birth and 147 d of age. The abomasal mucosas and pancreata wer...

To circumvent problems encountered in the synthesis of active chymosin in a number of bacteria and fungi, a recombinant DNA L-form expression system that directed the complete secretion of fully activable prochymosin into the extracellular culture medium was developed. The expression plasmid constructions involved the in-frame fusion of prochymosin cDNA minus codons 1 to 4 to streptococcal pyro...

In this paper, the effects of limited hydrolysis on functional properties, as well as on protein composition of laboratory-prepared pea protein isolates, were investigated. Pea protein isolates were hydrolyzed for either 15, 30 and 60 min with recombined chymosin (Maxiren). The effect of enzymatic action on solubility, emulsifying and foaming properties at different pH values (3.0; 5.0; 7.0 and...

In the structural-based mutagenesis of Mucor pusillus pepsin (MPP), understanding how κ-casein interacts with MPP is a great challenge for us to explore. Chymosin-sensitive peptide is the key domain of κ-casein that regulates milk clotting through the specific proteolytic cleavage of its peptide bond (Phe¹⁰⁵-Met¹⁰⁶) by MPP to produce insoluble para-κ-casein. Here, we built the model of this lar...