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1
Content available remote Peptydy sygnałowe roślin
EN
Subject of the paper are a signaling plant peptides. There are peptides of a new generation, regulating processes of growth, differentiation and other physiological plant function. Here will presented the literature data and results of our studies. Especially the results of structure/function relationship studies will presented for systemin and phytosulfokine - α.
2
Content available remote Gonadotropowe hormony peptydowe owadów
EN
Gonadotropic peptides are a new generation of peptide hormone regulators of methamorphosis and reproduction of insects. These substances have been isolated from ovarian, oviduct or brain of insects. The subject of this paper is a several insect gonadotropic peptides which: -stimulate ovarian growth, -modulate biosynthesis of trypsine, -speed up vitellogenesis, -stimulate ecdysteroid production, -inhibit serine proteases, -have other activities. Basing on the literaturę data and results of our investigations their structure and biological properties are presented.
EN
The object of these investigations was synthesis and biological evaluation of new analogues of proctolin (H-Arg-Tyr-Leu-Pro-Thr-OH) modified at position 4 of the peptide chain by natural or non-natural amino acid residues, such as: Phe (1), D-Phe (2), Phg (3), D-Phg (4), N-Me-Ala (5), N-Me-Val (6), N-Me-Leu (7), Tyr (8), Arg (9), Lys (10), Nva (11), Acp (12), Ser (13), _-Abu (14), and _3,4-Pro (15). Synthesis was performed by classical solid-phase method. Myotropic activity of proctolin analogues was assayed in vitro on the semi-isolated heart of the yellow mealworm Tenebrio molitor. Analogues 1,9, and 14 retained about 50% of proctolin activity. Other analogues showed about 20% activity or were inactive. The importance of the hydrophobic amino acid residues at position 4 for the myotropic activity of proctolin was inferred.
EN
New analogues of insect neuromodulator proctolin (H-Arg-Tyr-Leu-Pro-Thr-OH) modified in position 2 and 3 of the peptide chain by natural or non-natural amino acid residues were synthesized. For modification of proctolin at position 2 a series of novel L-homophenylalanine derivatives H-Hpa(4-NO2)-OH (1), Boc-Hpa(4-NO2)-OH (2), Boc-Hpa(4-NH2)-OH (3), Boc-Hpa(4-NH-Z)-OH (4), Boc-Phg(4-Me2N)-OH (5) were obtained. The following two groups of proctolin analogues modified at positions 2 and 3such as: 1/ H-Arg-X2-Leu-Pro-Thr-OH, where X2 = Hpa (6), Hpa(4-NO2) (7), Hpa(4-NH2) (8), and Hpa(4-N-Me2) (9), and 2/ H-Arg-Tyr-X3-Pro-Thr-OH, where X3 = Ile (10), Phe (11), Arg (12), Sar (13), Nva (14), Nle (15), Asn (16), Asp (17), Gln (18), Glu (19), Lys (20), and _-Abu (21), were synthesized. Myotropic activity of proctolin analogues (6-21) was assayed in vitro on the semi-isolated heart of the yellow mealworm Tenebrio molitor. Analogues 10-12 and 20 retained more that 60% of proctolin activity. Other analogues showed a weak or none activity.
EN
New analogues of insect neuromodulator proctolin (H-Arg-Tyr-Leu-Pro-Thr-OH), modified in position 2 of the peptide chain by L- or D-phenylglycine and its 4-substituted derivatives were synthesized. For modification of proctolin a series of novel L- or D-phenylglycine derivatives H-Phg(4-NO2)-OH (1), Boc-Phg(4-NO2)-OH (2), Boc- Phg(4-Me2N)-OH (3), H-Phg(4-OBzl)-OH (4), Boc-Phg(4-OBzl)-OH (5), H-D-Phg(4-NO2)-OH (6), Boc-D-Phg(4-NO2,)-OH (7), Boc-D-Phg(4-Me2N)-OH (8), were used. The following proctolin analogues were synthesized: H-Arg-Phg-Leu-Pro- Thr-OH (9), H-Arg-D-Phg-Leu-Pro-Thr-OH (10), H-Arg-Phg(4-OH)-Leu-Pro-Thr-OH (11), H-Arg-D-Phg(4-OH)-Leu-Pro-Thr-OH (12), H-Arg-Phg(4-NO2)-Leu- Pro-Thr-OH (13), H-Arg-D-Phg(4-NO2)-Leu-Pro-Thr-OH (14), H-Arg- Phg(4-NH2)-Leu-Pro-Thr-OH (15), H-Arg-D-Phg(4-NH2)-Leu-Pro-Thr-OH (16), H-Arg-Phg(4-NMe2)-Leu-Pro-Thr-OH (17), H-Arg-D-Phg(4-NMe2)-Leu-Pro-Thr-OH (18). Myotropic activity of proctolin analogues 9-18 was assayed in vitro on the semi-isolated heart of the mealworm Tenebrio molitor and on the foregut of the locust Schistocerca gregaria. All analogues showed a weak or none activity.
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