Expression of recombinant calf prochymosin in mammalian cell culture.
The calf preprochymosin cDNA was cloned into an extrachromosomal mammalian cell expression vector containing Epstein-Barr virus sequences using polymerase chain reaction. Transfection of HeLa cells yielded Hygromycin B resistant cell clones, expressing immunoreactive prochymosin, which was quantitatively secreted into the culture medium. Based on Western blotting we estimated that selected cell clones produced about 10-20 mg prochymosin per liter in 20 h. The biological activity of the secreted chymosin was confirmed by milk clotting assay.
Institute of Chemical Physics and Biophysics, Estonian Academy of Sciences, Tallinn.
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Kolmer
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Ulmanen
D001483:Base Sequence; D002478:Cells, Cultured; D012085:Chymosin / Q000096:biosynthesis* / Q000235:genetics; D003001:Cloning, Molecular; D004792:Enzyme Precursors / Q000096:biosynthesis* / Q000235:genetics; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis
D004792:Enzyme Precursors; D011994:Recombinant Proteins; C034675:preprorennin; C032443:prorennin; D012085:Chymosin