N-terminal amino acid sequence of human urinary prokallikrein

The N-terminal amino acid sequences of human urinary prokallikrein and kallikrein have been determined. Their amino acid sequences are as follows. (Formula; see text) The results showed that prokallikrein comprises an additional seven amino acids at the amino terminus of the kallikrein, of which the sequence is (H2N)Ala-Pro-Pro-Ile-Gln-Ser-Arg(COOH). Comparison of the structure of this peptide with those of other proteins revealed extensive sequence identity with the propeptide portions of rat and mouse tissue kallikreins, that were predicted from the preproenzyme-encoded nucleotide sequences. The amino acid sequence of the peptide was also highly homologous to that of the propeptide portion of EGF-binding protein, that was predicted from the nucleotide sequence, and that of the alpha-subunit of NGF. The N-terminal amino acid sequence of kallikrein was completely identical to the reported one (Lottspeich, F., et al. (1979) Hoppe-Seyler's Z. Physiol. Chem. 360, 1947-1950) and shows considerable amino acid sequence homology with the porcine and rat pancreatic kallikreins. As far as the present results are concerned, it is strongly indicated that the inactive kallikrein in human urine is a tissue type prokallikrein which is activated on the release of the N-terminal peptide consisting of seven amino acids.

Synthesis of 2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole derivatives and their central nervous system activities

The synthesis and some pharmacological effects of cis- and trans-2-substituted 2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole derivatives are described. In these derivatives, the substituents of the 2, 5 and 8 position, together with the relative configuration of the 4a and 9b position, influenced the potency of the central nervous system activities. A cis-2-[3-(p-fluorobenzoyl)propyl] analogue (5k) of carbidine (1) possessed not only thymoleptic-like biological activity but had more potent neuroleptic activity than the parent drug.