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In vitro and in vivo antimicrobial effect of lasioglossins on the Candida albicans
Kašperová, A. ; Turánek, J. ; Čeřovský, Václav ; Raška, M.
Lasioglossins represent a new group of amphipathic α-helical peptides with significant antimicrobial effect on the Candida albicans. This study examines the antifungal activity of two peptides LL-III and all D-LL-III as measured by the suppression of Candida proliferation and suppression of induced morphological differentiation both in in vitro and in vivo assays. In the in vitro Candida proliferation assay, the inhibitory effect of lasioglossins LL-III and all D-LL-III was more than 70% within 24 h and more than 84% after 48 h of incubation (final concentration of either peptide was 17.5 .mu.M). Delaying of blastoconidial transition to hyphae in vitro and tendency to suppress vaginal candidiasis in experimental mice were detected.
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Lucifensin, a peptide behind the maggot therapy
Čeřovský, Václav
The larvae of the green bottle fly (Lucilia sericata) are routinely used as a medication for the treatment of necrotic, non-healing and highly infected wound in many hospitals all over the world. We have identified and determined primary structure of the defensin originated from the immune system of Lucilia sericata larvae and named it lucifensin. This is 40 amino acid residues and three intramolecular disulfide bridges peptide. The synthetic lucifensin was active against Gram-positive bacteria and was not hemolytic. We studied the importance of lucifensin disulfide bridges and the N-terminal part of its molecule for the structure and for antimicrobial activity.
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Analysis of antimicrobial peptides by capillary electrophoresis
Ehala, Sille ; Niederhafner, Petr ; Čeřovský, Václav ; Řezanka, P. ; Sýkora, D. ; Král, V. ; Kašička, Václav
Capillary electrophoresis was used for the purity degree determination of new antimicrobial peptides: octadecapeptide melectin and tetradecapeptide mastoparan PDD-B, and their synthetic analogues. Besides, four semiempirical models correlating electrophoretic mobilities of these peptides with their charge and size (relative molecular mass) were applied to predict their probable structures in solution. Additionally, capillaries coated with gold nanoparticles were employed for the separation of mixtures of antimicrobial peptides.
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Design of stable antimicrobial peptides through hydrocarbon stapling
Chapuis, Hubert Jean ; Slaninová, Jiřina ; Monincová, Lenka ; Bednárová, Lucie ; Čeřovský, Václav
From the venom of wild bee Lasioglossum laticeps we have recently isolated novel antimicrobial peptides named lasioglossins. One of them, LL-III (VNWKKILGKIIKVVK-NH2), is an amphipathic α-helical peptide which shows strong antimicrobial properties and a low hemolytic activity. We anticipated that the incorporation of an all-hydrocarbon staple (bridge) into the LL-III sequence could increase its propensity to form an α-helix and lead to an improvement of its proteolytic stability as well as increase the antimicrobial activity. LL-III analogs featuring olefinic side chains in various positions were prepared by solid phase peptide synthesis. Ring closing olefin metatheses catalyzed by Grubbs-I catalyst were carried out on the solid support, either between i and i+4 positions or between i and i+7 positions.
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Melectin analogues: The influence of dendrimerization on antimicrobial and hemolytic activity
Niederhafner, Petr ; Šafařík, Martin ; Ježek, Jan ; Borovičková, Lenka ; Bednárová, Lucie ; Fučík, Vladimír ; Čeřovský, Václav ; Slaninová, Jiřina
Dimers and tetramers of MEP and MEP derivatives were synthesized on Fmoc-Lys(Fmoc)-Rink amide resin, the tetramer was obtained from the dimer C-terminally extended via Cys-Cys linkage. In general, the dendrimerization of MEP led to an increase of haemolytic activity but did not improve substantially its antimicrobial properties.
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Novel biologically active peptides from the venom of the solitary bee Macropis fulvipes (HYMENOPTERA: MELITTIDAE)
Monincová, Lenka ; Slaninová, Jiřina ; Voburka, Zdeněk ; Hovorka, Oldřich ; Fučík, Vladimír ; Borovičková, Lenka ; Bednárová, Lucie ; Buděšínský, Miloš ; Straka, J. ; Čeřovský, Václav
Two peptides (macropine-1 and macropin-2) were isolated, their structure determined by Edman degradation and mass spectrometry, which exhibited potent antimicrobial activity against both Gram-positive and -negative bacteria and moderate hemolytic activity against rat erythrocytes. We prepared several MAC-1 analogs to study the effect of their structure on antimicrobial and hemolytic activities.
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