D-Cecropin B: proteolytic resistance, lethality for pathogenic fungi and binding properties
| Autor: | C. B. Vigo, A.J. De Lucca, John M. Bland, T. J. Jacks, Joanne Peter, Thomas J. Walsh |
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| Rok vydání: | 2000 |
| Předmět: |
Antifungal Agents
medicine.medical_treatment Proteolysis Aspergillus flavus Microbial Sensitivity Tests Biology Microbiology Aspergillus fumigatus chemistry.chemical_compound Fusarium Chitin Cell Wall Ergosterol Candida albicans medicine Protease medicine.diagnostic_test fungi Proteolytic enzymes Stereoisomerism General Medicine Trypsin biology.organism_classification Aspergillus Infectious Diseases Biochemistry chemistry Insect Proteins Peptides Protein Binding medicine.drug |
| Zdroj: | Scopus-Elsevier |
| ISSN: | 1460-2709 1369-3786 |
| DOI: | 10.1080/mmy.38.4.301.308 |
| Popis: | L-Cecropin B (LCB) is a potent fungicidal peptide that is subject to proteolytic degradation by extracellular enzymes produced by Aspergillus flavus. We hypothesized that D-cecropin B (DCB), containing all D-amino acids, should resist proteolysis while retaining its fungicidal and target specificities. DCB was synthesized by solid phase methods using Fmoc chemistry. In vitro, at pH 6 x 0, DCB was lethal against the germinating conidia of A. flavus (LD90, 25 microM) and A. fumigatus (LD98, 25 microM) and for nongerminating and germinating conidia of Fusarium moniliforme (LD98, 1 x 25 microM) and F. oxysporum (LD95, 2 x 5 microM) at concentrations similar to those previously reported for LCB. It was lethal for Candida albicans with an LD98 at 12 x 5, microM. DCB was not active for the nongerminating conidia of A. fumigatus or A. flavus. Papain, trypsin, pepsin A and Staphylococcus aureus V8 protease degraded LCB but not DCB. Binding assays and circular dichroism showed DCB and LCB bound to cholesterol, ergosterol, beta-1,3-glucan, mannan and chitin. Data show that DCB retains the potent fungicidal properties of the L-form while being resistant to proteolytic enzymes that degrade the latter peptide. This study demonstrates that D-enantiomerization of cecropin B yields a novel fungicidal peptide, which resists proteolytic degradation and is lethal for pathogenic fungi. |
| Databáze: | OpenAIRE |
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