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Vymětal J, Bednárová L, Vondrášek J. Effect of TFE on the Helical Content of AK17 and HAL-1 Peptides: Theoretical Insights into the Mechanism of Helix Stabilization. J Phys Chem B 2016; 120:1048-59. [DOI: 10.1021/acs.jpcb.5b11228] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Mikulášková B, Zemenová J, Pirník Z, Pražienková V, Bednárová L, Železná B, Maletínská L, Kuneš J. Effect of palmitoylated prolactin-releasing peptide on food intake and neural activation after different routes of peripheral administration in rats. Peptides 2016; 75:109-17. [PMID: 26643957 DOI: 10.1016/j.peptides.2015.11.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 11/23/2015] [Accepted: 11/24/2015] [Indexed: 01/08/2023]
Abstract
Obesity is an escalating epidemic, but an effective non-invasive therapy is still scarce. For obesity treatment, anorexigenic neuropeptides are promising tools, but their delivery from the periphery to the brain is complicated by their peptide character. In order to overcome this unfavorable fact, we have applied the lipidization of neuropeptide prolactin-releasing peptide (PrRP), whose strong anorexigenic effect was demonstrated. A palmitoylated analog of human PrRP (h palm-PrRP31) was injected in free-fed Wistar rats by three routes: subcutaneous (s.c.), intraperitoneal (i.p) (both 5 mg/kg) and intravenous (i.v.) (from 0.01 to 0.5 mg/kg). We found a circulating compound in the blood after all three applications with the highest concentration after i.v. administration. This corresponds to the effect on food intake, which was also strongest after i.v. injection. Moreover, this is in agreement with the fact that the expression of c-Fos in specific brain regions involved in food intake regulation was also highest after intravenous application. Pharmacokinetic data are further supported by results obtained from dynamic light scattering and CD spectroscopy. Human palm-PrRP31 analog showed a strong tendency to micellize, and formation of aggregates suggested lower availability after i.p. or s.c. application. We have demonstrated that palm-PrRP influenced food intake even in free fed rats. Not surprisingly, the maximal effect was achieved after the intravenous application even though two orders of magnitude lower dose was used compared to both two other applications. We believe that palm-PrRP could have a potential as an antiobesity drug when its s.c. application would be improved.
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Vimberg V, Kuzma M, Stodůlková E, Novák P, Bednárová L, Šulc M, Gažák R. Hydnocarpin-Type Flavonolignans: Semisynthesis and Inhibitory Effects on Staphylococcus aureus Biofilm Formation. JOURNAL OF NATURAL PRODUCTS 2015; 78:2095-103. [PMID: 26273725 DOI: 10.1021/acs.jnatprod.5b00430] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A new, efficient, and general semisynthesis of hydnocarpin-type flavonolignans was developed and optimized, enabling gram-scale production of hydnocarpin D (2). Moreover, the syntheses of optically pure hydnocarpin isomers [(10R,11R)-hydnocarpin (1a), (10R,11R)-hydnocarpin D (2a), and (10S,11S)-hydnocarpin D (2b)], as well as the synthesis of isohydnocarpin (8), were achieved for the first time utilizing this new method. The synthesis is based on the two-step transformation of the readily available flavonolignans from milk thistle (Silybum marianum), accessible by isolation from the commercial extract silymarin. The first step relies on the regioselective formylation of the C-3 hydroxy group of the dihydroflavonol-type precursor using the Vilsmeier-Haack reagent, followed by formic acid elimination by triethylamine in the second step. The synthesized compounds were effective inhibitors of Staphylococcus aureus biofilm formation, with (10S,11S)-hydnocarpin D (2b) being the most potent inhibitor. Furthermore, the effect of glucose on biofilm formation was tested, and glucose decreased the biofilm inhibitory activity of 2b. Moreover, 2b increased the susceptibility of Staph. aureus to enrofloxacin.
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Šámal M, Chercheja S, Rybáček J, Vacek Chocholoušová J, Vacek J, Bednárová L, Šaman D, Stará IG, Starý I. An Ultimate Stereocontrol in Asymmetric Synthesis of Optically Pure Fully Aromatic Helicenes. J Am Chem Soc 2015; 137:8469-74. [DOI: 10.1021/jacs.5b02794] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Buchta M, Rybáček J, Jančařík A, Kudale AA, Buděšínský M, Chocholoušová JV, Vacek J, Bednárová L, Císařová I, Bodwell GJ, Starý I, Stará IG. Chimerical Pyrene-Based [7]Helicenes as Twisted Polycondensed Aromatics. Chemistry 2015; 21:8910-7. [DOI: 10.1002/chem.201500826] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Indexed: 01/13/2023]
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Kyjaková P, Dolejšová K, Krasulová J, Bednárová L, Hadravová R, Pohl R, Hanus R. The evolution of symmetrical snapping in termite soldiers need not lead to reduced chemical defence. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12540] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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57
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Machová I, Snášel J, Dostál J, Brynda J, Fanfrlík J, Singh M, Tarábek J, Vaněk O, Bednárová L, Pichová I. Structural and functional studies of phosphoenolpyruvate carboxykinase from Mycobacterium tuberculosis. PLoS One 2015; 10:e0120682. [PMID: 25798914 PMCID: PMC4370629 DOI: 10.1371/journal.pone.0120682] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 02/05/2015] [Indexed: 12/04/2022] Open
Abstract
Tuberculosis, the second leading infectious disease killer after HIV, remains a top public health priority. The causative agent of tuberculosis, Mycobacterium tuberculosis (Mtb), which can cause both acute and clinically latent infections, reprograms metabolism in response to the host niche. Phosphoenolpyruvate carboxykinase (Pck) is the enzyme at the center of the phosphoenolpyruvate-pyruvate-oxaloacetate node, which is involved in regulating the carbon flow distribution to catabolism, anabolism, or respiration in different states of Mtb infection. Under standard growth conditions, Mtb Pck is associated with gluconeogenesis and catalyzes the metal-dependent formation of phosphoenolpyruvate. In non-replicating Mtb, Pck can catalyze anaplerotic biosynthesis of oxaloacetate. Here, we present insights into the regulation of Mtb Pck activity by divalent cations. Through analysis of the X-ray structure of Pck-GDP and Pck-GDP-Mn2+ complexes, mutational analysis of the GDP binding site, and quantum mechanical (QM)-based analysis, we explored the structural determinants of efficient Mtb Pck catalysis. We demonstrate that Mtb Pck requires presence of Mn2+ and Mg2+ cations for efficient catalysis of gluconeogenic and anaplerotic reactions. The anaplerotic reaction, which preferably functions in reducing conditions that are characteristic for slowed or stopped Mtb replication, is also effectively activated by Fe2+ in the presence of Mn2+ or Mg2+ cations. In contrast, simultaneous presence of Fe2+ and Mn2+ or Mg2+ inhibits the gluconeogenic reaction. These results suggest that inorganic ions can contribute to regulation of central carbon metabolism by influencing the activity of Pck. Furthermore, the X-ray structure determination, biochemical characterization, and QM analysis of Pck mutants confirmed the important role of the Phe triad for proper binding of the GDP-Mn2+ complex in the nucleotide binding site and efficient catalysis of the anaplerotic reaction.
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Pazderková M, Profant V, Seidlerová B, Dlouhá H, Hodačová J, Jávorfi T, Siligardi G, Baumruk V, Bednárová L, Maloň P. Electronic circular dichroism of the chiral rigid tricyclic dilactam with nonplanar tertiary amide groups. J Phys Chem B 2014; 118:11100-8. [PMID: 25180568 DOI: 10.1021/jp5063463] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Electronic circular dichroism (ECD) of the spirocyclic dilactam 5,8-diazatricyclo[6,3,0,0(1,5)]undecane-4,9-dione has been measured in the extended wavelength range (170-260 nm) utilizing far-UV CD instrumentation including synchrotron radiation light source. The data of this model of two nonplanar tertiary amide groups interacting within the rigid chiral environment provided new information particularly about the shorter wavelength π-π* transition region below 190 nm. The interpretation using TDDFT calculations confirmed that effects of amide nonplanarity follow our previous observations on monolactams as far as amide n-π* transitions are concerned. ECD band in the n-π* transition region of the nonplanar diamide exhibits an identical bathochromic shift and its sign remains tied to the sense of nonplanar deformation in the same way. As far as n-π* transitions are concerned amide nonplanarity acts as a local phenomenon independently reflecting sum properties of single amide groups. On the other hand, CD bands associated with π-π* transitions (found between ∼170 to 210 nm) form an exciton-like couplet with the sign pattern determined by mutual orientation of the associated electric transition moments. This sign pattern follows predictions pertaining to a coupled oscillator. The influence of amide nonplanarity on π-π* transitions is only minor and concentrates into the shorter wavelength lobe of the π-π* couplet. The detailed analysis of experimental ECD with the aid of TDDFT calculations shows that there is only little interaction between effects of inherent chirality caused by nonplanarity of amide groups and amide-amide coupling. Consequently these two effects can be studied nearly independently using ECD. In addition, the calculations indicate that participation of other type of transitions (n-σ*, π-σ* or Rydberg type transitions) is only minor and is concentrated below 180 nm.
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Čujová S, Bednárová L, Slaninová J, Straka J, Čeřovský V. Interaction of a novel antimicrobial peptide isolated from the venom of solitary bee Colletes daviesanus with phospholipid vesicles and Escherichia coli cells. J Pept Sci 2014; 20:885-95. [PMID: 25123582 DOI: 10.1002/psc.2681] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/25/2014] [Accepted: 07/11/2014] [Indexed: 11/07/2022]
Abstract
The peptide named codesane (COD), consisting of 18 amino acid residues and isolated from the venom of wild bee Colletes daviesanus (Hymenoptera : Colletidae), falls into the category of cationic α-helical amphipathic antimicrobial peptides. In our investigations, synthetic COD exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria and Candida albicans but also noticeable hemolytic activity. COD and its analogs (collectively referred to as CODs) were studied for the mechanism of their action. The interaction of CODs with liposomes led to significant leakage of calcein entrapped in bacterial membrane-mimicking large unilamellar vesicles made preferentially from anionic phospholipids while no calcein leakage was observed from zwitterionic liposomes mimicking membranes of erythrocytes. The preference of CODs for anionic phospholipids was also established by the blue shift in the tryptophan emission spectra maxima when the interactions of tryptophan-containing COD analogs with liposomes were examined. Those results were in agreement with the antimicrobial and hemolytic activities of CODs. Moreover, we found that the studied peptides permeated both the outer and inner cytoplasmic membranes of Escherichia coli. This was determined by measuring changes in the fluorescence of probe N-phenyl-1-naphthylamine and detecting cytoplasmic β-galactosidase released during the interaction of peptides with E. coli cells. Transmission electron microscopy revealed that treatment of E. coli with one of the COD analogs caused leakage of bacterial content mainly from the septal areas of the cells.
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Stanchev S, Zawada Z, Monincová L, Bednárová L, Slaninová J, Fučík V, Čeřovský V. Synthesis of lucifensin by native chemical ligation and characteristics of its isomer having different disulfide bridge pattern. J Pept Sci 2014; 20:725-35. [PMID: 24920043 DOI: 10.1002/psc.2663] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 04/10/2014] [Accepted: 05/12/2014] [Indexed: 12/17/2022]
Abstract
The antimicrobial 40-amino-acid-peptide lucifensin was synthesized by native chemical ligation (NCL) using N-acylbenzimidazolinone (Nbz) as a linker group. NCL is a method in which a peptide bond between two discreet peptide chains is created. This method has been applied to the synthesis of long peptides and proteins when solid-phase synthesis is imcompatible. Two models of ligation were developed: [15+25] Ala-Cys and [19+21] His-Cys. The [19+21] His-Cys method gives lower yield because of the lower stability of 18-peptide-His-Nbz-CONH2 peptide, as suggested by density functional theory calculation. Acetamidomethyl-deprotection and subsequent oxidation of the ligated linear lucifensin gave a mixture of lucifensin isomers, which differed in the location of their disulfide bridges only. The dominant isomer showed unnatural pairing of cysteines [C1-6], [C3-5], and [C2-4], which limits its ability to form α-helical structure. The activity of isomeric lucifensin toward Bacillus subtilis, Staphylococcus aureus, and Micrococcus luteus was lower than that of the natural lucifensin. The desired product native lucifensin was prepared from this isomer using a one-pot reduction with dithiotreitol and subsequent air oxidation in slightly alkaline medium.
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Pechar M, Pola R, Laga R, Braunová A, Filippov SK, Bogomolova A, Bednárová L, Vaněk O, Ulbrich K. Coiled Coil Peptides and Polymer–Peptide Conjugates: Synthesis, Self-Assembly, Characterization and Potential in Drug Delivery Systems. Biomacromolecules 2014; 15:2590-9. [DOI: 10.1021/bm500436p] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Novotná M, Gažák R, Biedermann D, Di Meo F, Marhol P, Kuzma M, Bednárová L, Fuksová K, Trouillas P, Křen V. cis-trans Isomerization of silybins A and B. Beilstein J Org Chem 2014; 10:1047-1063. [PMID: 24991256 PMCID: PMC4077359 DOI: 10.3762/bjoc.10.105] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 04/04/2014] [Indexed: 12/27/2022] Open
Abstract
Methods were developed and optimized for the preparation of the 2,3-cis- and the 10,11-cis-isomers of silybin by the Lewis acid catalyzed (BF3∙OEt2) isomerization of silybins A (1a) and B (1b) (trans-isomers). The absolute configuration of all optically pure compounds was determined by using NMR and comparing their electronic circular dichroism data with model compounds of known absolute configurations. Mechanisms for cis-trans-isomerization of silybin are proposed and supported by quantum mechanical calculations.
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Pospíšil L, Bednárová L, Štěpánek P, Slavíček P, Vávra J, Hromadová M, Dlouhá H, Tarábek J, Teplý F. Intense Chiroptical Switching in a Dicationic Helicene-Like Derivative: Exploration of a Viologen-Type Redox Manifold of a Non-Racemic Helquat. J Am Chem Soc 2014; 136:10826-9. [DOI: 10.1021/ja500220j] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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64
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Monincová L, Veverka V, Slaninová J, Buděšínský M, Fučík V, Bednárová L, Straka J, Čeřovský V. Structure-activity study of macropin, a novel antimicrobial peptide from the venom of solitary bee Macropis fulvipes
(Hymenoptera: Melittidae). J Pept Sci 2014; 20:375-84. [DOI: 10.1002/psc.2625] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 02/03/2014] [Accepted: 02/14/2014] [Indexed: 11/06/2022]
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65
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Profantová B, Profant V, Zíma V, Kopecký V, Bednárová L, Zentz C, Baumruk V, Turpin PY, Štěpánek J. Protonation Effect of Tyrosine in a Segment of the SRF Transcription Factor: A Combined Optical Spectroscopy, Molecular Dynamics, and Density Functional Theory Calculation Study. J Phys Chem B 2013; 117:16086-95. [DOI: 10.1021/jp4099864] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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66
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Pazderková M, Profant V, Hodačová J, Šebestík J, Pazderka T, Novotná P, Urbanová M, Šafařík M, Buděšínský M, Tichý M, Bednárová L, Baumruk V, Maloň P. Nonplanar Tertiary Amides in Rigid Chiral Tricyclic Dilactams. Peptide Group Distortions and Vibrational Optical Activity. J Phys Chem B 2013; 117:9626-42. [DOI: 10.1021/jp405226k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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67
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Jančařík A, Rybáček J, Cocq K, Vacek Chocholoušová J, Vacek J, Pohl R, Bednárová L, Fiedler P, Císařová I, Stará IG, Starý I. Rapid Access to Dibenzohelicenes and their Functionalized Derivatives. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201301739] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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68
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Jančařík A, Rybáček J, Cocq K, Vacek Chocholoušová J, Vacek J, Pohl R, Bednárová L, Fiedler P, Císařová I, Stará IG, Starý I. Rapid Access to Dibenzohelicenes and their Functionalized Derivatives. Angew Chem Int Ed Engl 2013; 52:9970-5. [DOI: 10.1002/anie.201301739] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/13/2013] [Indexed: 11/11/2022]
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69
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Kalachova L, Pohl R, Bednárová L, Fanfrlík J, Hocek M. Synthesis of nucleosides and dNTPs bearing oligopyridine ligands linked through an octadiyne tether, their incorporation into DNA and complexation with transition metal cations. Org Biomol Chem 2013; 11:78-89. [PMID: 23090069 DOI: 10.1039/c2ob26881g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Modified nucleosides (dA(R)s and dC(R)s) bearing bipyridine or terpyridine ligands attached through an octadiyne linker were prepared by single-step aqueous-phase Sonogashira cross-coupling of 7-iodo-7-deaza-2'-deoxyadenosine and 5-iodo-2'-deoxycytidine with the corresponding bipyridine- or terpyridine-octadiynes and were triphosphorylated to the corresponding nucleoside triphosphates (dA(R)TPs and dC(R)TPs). The modified dN(R)TPs were successfully incorporated into the oligonucleotides by primer extension experiment (PEX) using different DNA polymerases and the PEX products were used for post-synthetic complexation with divalent metal cations. The complexation of these DNAs containing flexibly-tethered ligands was compared with the previously reported ones bearing rigid acetylene-linked ligands suggesting the possible formation of both inter- and intra-strand complexes with Ni(2+) or Fe(2+).
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Pazderková M, Bednárová L, Dlouhá H, Flegel M, Lebl M, Hlaváček J, Setnička V, Urbanová M, Hynie S, Klenerová V, Baumruk V, Maloň P. Electronic and vibrational optical activity of several peptides related to neurohypophyseal hormones: Disulfide group conformation. Biopolymers 2012; 97:923-32. [DOI: 10.1002/bip.22105] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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71
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Chapuis H, Slaninová J, Bednárová L, Monincová L, Buděšínský M, Čeřovský V. Effect of hydrocarbon stapling on the properties of α-helical antimicrobial peptides isolated from the venom of hymenoptera. Amino Acids 2012; 43:2047-58. [DOI: 10.1007/s00726-012-1283-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 03/28/2012] [Indexed: 10/28/2022]
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72
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Wald T, Bednárová L, Osička R, Pachl P, Šulc M, Lyngstadaas SP, Slaby I, Vondrášek J. Biophysical characterization of recombinant human ameloblastin. Eur J Oral Sci 2012; 119 Suppl 1:261-9. [DOI: 10.1111/j.1600-0722.2011.00913.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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73
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Pechar M, Pola R, Laga R, Ulbrich K, Bednárová L, Maloň P, Sieglová I, Král V, Fábry M, Vaněk O. Coiled Coil Peptides as Universal Linkers for the Attachment of Recombinant Proteins to Polymer Therapeutics. Biomacromolecules 2011; 12:3645-55. [DOI: 10.1021/bm200897b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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74
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Ceřovský V, Slaninová J, Fučík V, Monincová L, Bednárová L, Maloň P, Stokrová J. Lucifensin, a novel insect defensin of medicinal maggots: synthesis and structural study. Chembiochem 2011; 12:1352-61. [PMID: 21560219 DOI: 10.1002/cbic.201100066] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Indexed: 12/13/2022]
Abstract
Recently, we identified a new insect defensin, named lucifensin that is secreted/excreted by the blowfly Lucilia sericata larvae into a wound as a disinfectant during the medicinal process known as maggot therapy. Here, we report the total chemical synthesis of this peptide of 40 amino acid residues and three intramolecular disulfide bridges by using three different protocols. Oxidative folding of linear peptide yielded a peptide with a pattern of disulfide bridges identical to that of native lucifensin. The synthetic lucifensin was active against Gram-positive bacteria and was not hemolytic. We synthesized three lucifensin analogues that are cyclized through one native disulfide bridge in different positions and having the remaining four cysteines substituted by alanine. Only the analogue cyclized through a Cys16-Cys36 disulfide bridge showed weak antimicrobial activity. Truncating lucifensin at the N-terminal by ten amino acid residues resulted in a drop in antimicrobial activity. Linear lucifensin having all six cysteine residues alkylated was inactive. Circular dichroism spectra measured in the presence of α-helix-promoting compounds showed different patterns for lucifensin and its analogues. Transmission electron microscopy revealed that Bacillus subtilis treatment with lucifensin induced significant changes in its envelope.
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Maloň P, Bednárová L, Straka M, Krejčí L, Kumprecht L, Kraus T, Kubáňová M, Baumruk V. Disulfide chromophore and its optical activity. Chirality 2010; 22 Suppl 1:E47-55. [DOI: 10.1002/chir.20851] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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