1. Prochymosin in solution in the presence of 8 M-urea is fully unfolded, as indicated by its fluorescence spectrum, fluorescence quenching behaviour and far-u.v.c.d. spectrum. 2. Equilibrium studies on the unfolding of prochymosin and pepsinogen by urea were carried out at pH 7.5 and pH 9.0. The results indicate that the stabilization energies of the two proteins are identical at pH 7.5, but t...

objectives: in present research we evaluate the expression of this critical enzyme in a eukaryotic system for future use in cheese industry. materials and methods: we have cloned bovine prochymosin gene in methylotrophic yeast, p. pastoris, using ppic9k as an expression vector. the recombinant plasmid was transformed into the host by electroporation, and it was expressed in optimum con­ditions...

Prochymosin is one of the most important aspartic proteinases used as a milk-clotting enzyme in cheese production. In the present investigation we report sequence of cDNA encoding goat ( Capra hircus ) preprochymosin and compare its nucleotide and deduced amino acid sequences with sequences of other ruminants preprochymosin. As bovine prochymosin, the caprine prochymosin cDNA encodes 365 amino ...

prochymosin is one of the most important aspartic proteinases used as a milk-clotting enzyme in cheese production. in the present investigation we report sequence of cdna encoding goat ( capra hircus ) preprochymosin and compare its nucleotide and deduced amino acid sequences with sequences of other ruminants preprochymosin. as bovine prochymosin, the caprine prochymosin cdna encodes 365 amino ...

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...

Activation of the four separate components of prochymosin (prorennin) at pH 5.0 demonstrated that each zymogen was the precursor to an electrophoretically distinct chymosin (rennin). When the increase in milk-clotting activity with time was analysed, the mechanism of activation of unfractionated prochymosin, individual prochymosin components, and a mixture of the prochymosin fractions at pH 5.0...

DNA complementary to calf stomach mRNA has been synthesised and inserted into the Pst1 site of pAT153 by G-C tailing. Clones containing sequences coding for prochymosin were recognised by colony hybridisation with cDNA extended from a chemically synthesised oligodeoxynucleotide primer, the sequence of which was predicted from the published amino acid sequence of calf prochymosin. Two clones wer...

To express bovine chymosin in yeast, we amplified the prochymosin gene from the plasmid pMD18T-Prochy by PCR, and then cloned the gene into the expression vector pPICZaA, resulting in pPICZaA-Prochy. Pichia pastoris GS115 was used as host cells. Integration of the prochymosin cDNA into the Pichia pastoris genome was confirmed by PCR and sequencing analysis. Chymosin was expressed in Pichia past...