DE2943132A1 - Nona:peptide cpds. with pancreozymin-cholecystokinin activity - contg. sulphonated tyrosine residue, useful for controlling gall bladder and pancreas functions - Google Patents

Abstract

(A) Novel pancreoxymin-cholecystokinin (P-C) active peptides (I) consists of the C-terminal section of P-C 25-33 in which (a) aminoacid 25 carries a strongly basic gp., (b) 28 has hydrophilic character of the hydroxyamino acid type and (c) 31 has strongly hydrophobic character of the type shown by amino acids with an aliphatic side chain. Pref. (I) are nonapeptides with Thr, Ser or hydroxy-Pro as unit 28 and Nle, Leu, nor-Val, or alpha-aminobutyric acid as unit 31; esp. they have formula H-X-Asp-Tyr(SO3H)-Y-Gly-Trp-Z -Asp-Phe-NH2 (X = Arg, homo-Arg, nor-Arg, N epsilon, N epsilon-dialkyl-lysine, or N delta, N delta-dialkyl ornithine; Y = Thr, Ser or hydroxy-Pro; Z = nor-Leu, nor-Val or alpha-aminobutyric acid). (B) Also new are tyrosine-O-sulphate barium salt (II) and its N-acyl derivs. (I) are more active than pancreozymin and can be used to control function of the gall bladder and enzyme secretion by the pancreas. They are more stable than the natural hormone (having methionine at positions 28 and 31) and are easier to prepare. (II) is an intermediate for (I), and other proteins and peptides, and allows Tyr(SO3H) to be introduced during standard synthetic steps without the need for a subsequent sulphonation.

Description

Pancreozymin Cholecystokinin Active Peptides

The invention relates to the peptides specified in the claims.

In particular, it relates to nonapeptides with the carboxyl terminus Sequence of pancreozymin cholecystokinin 25-33 such that the amino acid residue 25 carries a strongly basic group, the amino acid residue 28 has a hydrophilic character of the hydroxyamino acid type such as threonine, serine, hydroxy-proline and the amino acid residue 31 has a strongly hydrophobic character of the amino acid with aliphatic type Has side chains such as norleucine, norvaline and aminobutyric acid. Decisive for the last two variations of the natural sequence is that the "total polarity character", due to the methionine residues present in the natural product, due to the above specific exchange in size is retained.

The invention also relates to the use of the invention Peptides as Pancreozymin Cholecystokinin Active Compounds.

The amino acid residue 28 has to fully maintain the hormone activity to be a more hydrophilic residue compared to the natural building block methionine, such as e.g. threonine, serine or hydroxy-proline, while amino acid residue 31 is opposite the natural building block methionine must be a more hydrophobic amino acid residue, like e.g. norleucine, norvaline or s-aminobutyric acid.

The simultaneous exchange of items 28 and 31 of the natural substance, i.e. the occupation of the nonapeptide sequence with residues Y and Z has to maintain the "overall hydrophobic-hydrophilic character" of the nonapeptide in order to to ensure optimal hormonal activity.

At the same time, this exchange of methionine residues is carried out by the building blocks Y and Z achieve an increase in the stability of the nonapeptides (oxidation the methionine to methionine S-oxide residues leads to the loss of biological activity!) and brought about a simplification of the synthesis.

The occupation of position 25 (i.e. amino acid residue X) with a strongly basic amino acid, e.g. in analogy to the natural product sequence with arginine, but also with the homo- and nor-compounds of this amino acid or other strong basic amino acids, increases the stability of the tyrosine-O-sulfate group in the nonapeptides considerably. Production, processing and storage of the hormone-active This makes peptides much easier.

The production of the peptides according to the invention takes place according to per se known manner, as described, for example, by Moroder, L., L. Wilschowitz, E. Jaeger, S. Knof, P. Thamm and E. Wünsch in: "Hormonal Receptors in Digestive Tract Physiology "(G. Rosselin et al. Eds.), Elsevier / North-Holland Biomedical Press, Amsterdam 1979, pp. 129-135.See also Moroder, L., L. Wilschowitz, E. Jaeger, S. Knof, P. Thamm and E. Wünsch (1979) Hoppe Seyler's Z. Physiol. Chem. 360, 787-790).

l. using this method, the following connection could be established, for example: H-Arg-Asp-Tyr (SO3H) -Thr-Gly-Trp-Nle-Asp-Phe-NH2: amino acid analysis (calculated Values in brackets) of the acidic hydrolyzate (6H IICl / 1100C / 243tdn with the addition of 2.5% thioglycolic acid): Arg 1.00 (1) As 1.92 (2) Tyr 1.00 (1) Thre 1.03 (1) Gly 0.98 (1) Trp 0.91 (1) Nle 1.02 (1) Phe 1.00 (1) of the AP-M; Degradation: Arg 1.00 (1) dsp 1.96 (2) Tyr (SO3H) 0.98 (1) Thr 1.05 (1) Gly 1.00 (1) Trp 1.00 (1) lTle 1.01 (1) Phe 1.00 (1); thin layer chromatography (HPTLC Bertigplatten Kieselgel uG, Merck AG, Darmstadt) uniformly in n-butanol / acetic acid Pyridine / water (60: 6: 40: 24); uniform according to high pressure liquid chromatography [Column: µ-Bondapak C 18; eluent: 29% acetonitrile + 71C ',' 0.0111 ammonium acetate buffer, pE 4.0; isocratic] and carrier-free electrophoresis [chamber electrolyte: 0.1H ammonium acetate Buffer, pH 8.3; Electrode distance: 50cm at 1500V]; Tyr / Trp - 0.0 (according to UV measurement).

Claims (6)

Claims P ig pancreozymin cholecystokinin active peptides with the carboxyl terminal sequence of pancreozymin cholecystokinin 25-33, such as that the amino acid residue 25 carries a strongly basic group, the amino acid residue 28 has a hydrophilic character of the hydroxy amino acid type and the amino acid residue 31 has a strongly hydrophobic character of the amino acid type with aliphatic side chains owns. 2. Peptide according to claim 1, characterized in that it is a nonapeptide is. 3. Peptide according to claim 1 or 2, characterized in that the Amino acid residue 28 is threonine, serine or hydroxy proline. 4. Peptide according to one of the preceding claims, characterized in that that amino acid residue 31 is norleucine, norvaline or i-aminobutyric acid. 5. Nonapeptides of the sequence H-X-Asp-Tyr (S03H) -Y-Gly-Trp-Z-Asp-Phe-NH2 where X arginine, homoarginine, norarginine, Nt, N # -dialkyllysine, N @ or Nz-dialkylornithine, Y threonine, serine or hydroxy-proline and Z norleucine, norvaline or aminobutyric acid is. 6. Nonapeptide of the sequence H-Arg-Asp-Tyr (SO3H) -Thr-Gly-Trp-Nle-Asp-Phe-NH2.