Bionebraska, Inc.

Carlsberg A/s

Restoragen, Inc.

Dennis B Henriksen

Fred W Wagner

Jay S Stout

Bruce E Partridge

Shane Manning

Bart Holmquist

Julie A Frank

Klaus Breddam

Barton Holmquist

Ole Buchardt

A process for the recombinant preparation of a calcitonin fragment and the use of the fragment in the preparation of calcitonin and related analogs is provided. The process includes recombinantly forming a fusion protein which includes the calcitonin fragment linked to a carbonic anhydrase. The recombinantly formed fusion protein is subsequently cleaved to produce a polypeptide which includes the calcitonin fragment. A method for producing a calcitonin carba analog which includes condensing a desaminononapeptide with the recombinantly formed calcitonin fragment is also provided.

Recombinant preparation of calcitonin fragments and use thereof in the preparation of calcitonin and related analogs

The method of the invention provides for the formation of a recombinant polypeptide which has been modified at the C-terminal end through the use of a transpeptidation process. The method is suitable for modifying recombinant polypeptides of any source including those which may be commercially available, those derived from recombinant single copy or multicopy polypeptide constructs, or those derived from single or multicopy recombinant fusion protein constructs. The transpeptidation reaction involves contacting an endopeptidase enzyme with a recombinant polypeptide to substitute an addition unit, of one or more amino acids, for a leaving unit, linked to a core polypeptide through a cleavage site recognized by the endopeptidase enzyme. Recombinant polypeptides derived from multicopy polypeptide constructs may be cleaved from the multicopy polypeptide at the N-terminal and C-terminal ends and simultaneously under go substitution of the leaving unit by the desired addition unit. The invention utilizes known and newly discovered cleavage recognition sites to effectuate the desired modification products.

Enzymatic method for modification of recombinant polypeptides

A method for the production of C-terminal amidated recombinant peptides is provided. The method employs a recombinant protein construct having multiple copies of a target peptide linked by intraconnecting peptides. The intraconnecting peptides permit the multicopy construct to be selectively reacted to produce product peptides having a C-terminal .alpha.-carboxamide. A recombinant gene containing a DNA sequence coding for the recombinant protein construct and an expression cassette, an expression vector and a transformed cell including the recombinant gene are also provided.

Production of C-terminal amidated peptides from recombinant protein

Recombinant preparation of calcitonin fragments and use thereof in the

A process for preparing C-terminally amidated peptides, Peptide-NH.sub.2, is presented. In a first step, a substrate component is reacted with a nucleophile component in the presence of trypsin or a carboxypeptidase using as nucleophile a compound NH.sub.2 -R to form a first reaction product Peptide-NH-R. In a second step, the first reaction product is non-enzymatically chemically cleaved to form the C-terminally amidated product, Peptide-NH.sub.2. The substrate component is selected from a) peptide derivatives Peptide-X-Y, where X is an amino acid or peptide residue and Y is OH, OMe or C-terminal modification and c) C-terminally esterified peptides, Peptide-OR', where R' is alkyl, aryl, heteroaryl, or aralkyl. The nucleophile component is selected from ##STR1## wherein A-F and A'-E' are carbon atoms or up to two hetero atoms, Y is H, alkyl, aryl, aralkyl, oxo or carboxy, X.sup.1 -X.sup.5 are H or various substituents. The cleavage may be induced by photolysis, solvolysis, reduction, rearrangement elimination, or oxidation. The process may be adapted to enzymatic synthesis and lends itself to C-terminal amidation of many types of peptides.

Process for the preparation of C-terminally amidated peptides

Enzymatic method for modification or recombinant polypeptides

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Lincoln, NE, United States of America

Dennis B Henriksen