Peptides with 6-Aminohexanoic Acid: Synthesis and Evaluation as Plasmin Inhibitors.

Fifteen new peptide derivatives of ɛ-aminocaproic acid (EACA) containing the known fragment -Ala-Phe-Lys- with an affinity for plasmin were synthesised in the present study. The synthesis was carried out a solid phase. The following compounds were synthesised: H-Phe-Lys-EACA-X, H-d-Ala-Phe-Lys-EACA-X, H-Ala-Phe-Lys-EACA-X, H-d-Ala-Phe-EACA-X and H-Ala-Phe-EACA-X, where X = OH, NH and NH-(CH)-NH.

Antimicrobial peptides and their analogs: searching for new potential therapeutics.

Antimicrobial peptides (AMPs) are an essential part of innate immunity. These compounds have been considered as potential therapeutics because of their broad-spectrum activities and proven ability to avoid antimicrobial resistance, but their clinical and commercial developments have some limitations, such as susceptibility to proteases and a high cost of peptide production. To overcome these problems, many researchers have tried to develop short active peptides, their modifications and mimics with better properties while retaining their basic features of natural AMPs such as cationic charge and the amphipathic structure.

Effect of short peptides containing lysine and epsilon-aminocaproic acid on fibrinolytic activity of plasmin and topoisomerase II action on supercoiled DNA.

Effects of eight short peptides containing lysine and epsilon-aminocaproic acid (EACA) on prolongation of the clot lysis time, as well as hemolytic and antibacterial activities were investigated. Interaction with plasmids pBR322 and pUC19 with the use of ethidium bromide assay and determination of influence on the activity of topoisomerase I and II were also tested. Examined compounds inhibited fibrinolytic activity of plasmin and five of them were more active than EACA.

Amino and chlorambucil analogues of pentamidine--synthesis and biological examinations.

The amino analogues of pentamidine with a polymethylene (n = 3 - 6) chain and their chlorambucil derivatives were synthesized. The obtained compounds revealed cytotoxic effect on MCF-7 human breast cancer cell line (IC50 = 22 - 95 +/- 2 pM), mainly by the induction of apoptosis. The topoisomerase I/II inhibition assay and the ethidium displacement assay with the use of pBR322 plasmid DNA were used to the study of mechanism by which the obtained compounds could act.

Tripeptides with non-code amino acids as potential serine proteases inhibitors.

Eight peptides of the general H-D-Ser-AA-Arg-OH formula, where AA = phenylglycine, phenylalanine, homophenylalanine, cyclohexylglycine, cyclohexylalanine, homocyclohexylalanine, α-methylphenylalanine and 1-aminocyclohexyl carboxylic acid were obtained and tested for their effect on the amidolytic activities of urokinase, thrombin, trypsin, plasmin, t-PA and kallikrein. We tested the hemolytic activity of the peptides against porcine erythrocytes and the antitumor activity against the human breast cancer cells, standard MCF-7 and estrogen-independent MDA-MB-231. The most active compounds were H-D-Ser-Chg-Arg-OH towards thrombin and H-D-Ser-Phg-Arg-OH towards plasmin with K(i) value 5.