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81.
Ivana Cacciatore Mara Di Giulio Erika Fornasari Antonio Di Stefano Laura Serafina Cerasa Lisa Marinelli Hasan Turkez Emanuela Di Campli Soraya Di Bartolomeo Iole Robuffo Luigina Cellini 《PloS one》2015,10(4)
Objective
The increasing prevalence of antibiotic-resistant bacterial infections led to identify alternative strategies for a novel therapeutic approach. In this study, we synthesized ten carvacrol codrugs – obtained linking the carvacrol hydroxyl group to the carboxyl moiety of sulphur-containing amino acids via an ester bond – to develop novel compounds with improved antimicrobial and antibiofilm activities and reduced toxicity respect to carvacrol alone.Method
All carvacrol codrugs were screened against a representative panel of Gram positive (S. aureus and S. epidermidis), Gram negative (E. coli and P. aeruginosa) bacterial strains and C. albicans, using broth microdilution assays.Findings
Results showed that carvacrol codrug 4 possesses the most notable enhancement in the anti-bacterial activity displaying MIC and MBC values equal to 2.5 mg/mL for all bacterial strains, except for P. aeruginosa ATCC 9027 (MIC and MBC values equal to 5 mg/mL and 10 mg/mL, respectively). All carvacrol codrugs 1-10 revealed good antifungal activity against C. albicans ATCC 10231. The cytotoxicity assay showed that the novel carvacrol codrugs did not produce human blood hemolysis at their MIC values except for codrugs 8 and 9. In particular, deepened experiments performed on carvacrol codrug 4 showed an interesting antimicrobial effect on the mature biofilm produced by E. coli ATCC 8739, respect to the carvacrol alone. The antimicrobial effects of carvacrol codrug 4 were also analyzed by TEM evidencing morphological modifications in S. aureus, E. coli, and C. albicans.Conclusion
The current study presents an insight into the use of codrug strategy for developing carvacrol derivatives with antibacterial and antibiofilm potentials, and reduced cytotoxicity. 相似文献82.
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86.
Pasquale V Romano VJ Rupnik M Dumontet S Cižnár I Aliberti F Mauri F Saggiomo V Krovacek K 《Folia microbiologica》2011,56(5):431-437
This pilot study was carried out to evaluate the occurrence of Clostridium difficile in marine environments and in edible shellfish. Samples of seawater, sediment, and zooplankton were collected at five sampling
stations in the Gulf of Naples. Six samples of edible shellfish, furthermore, were obtained: two from mussel farms and four
from wholesalers. The isolation and the characterization of C. difficile strains were carried out using selective media and molecular techniques, respectively. C. difficile was isolated from nine of the 21 samples investigated. Shellfish and zooplankton showed the highest prevalence of positive
samples. No C. difficile was detected in marine sediment. Majority of the C. difficile isolates were toxin A/B positive. Six known different PCR ribotypes (003, 005, 009, 010, 056, and 066) were identified, whereas
one strain may represent a new PCR ribotype. C. difficile may be present in the marine environment in Southern Italy, including shellfish and zooplankton. This study is reporting
the isolation of C. difficile from zooplankton, clams, and mussels and pointing out a new possible route to exposure to C. difficile of healthy individuals in the community. 相似文献
87.
Pavan S Schiavulli A Appiano M Marcotrigiano AR Cillo F Visser RG Bai Y Lotti C Ricciardi L 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(8):1425-1431
The powdery mildew disease affects several crop species and is also one of the major threats for pea (Pisum sativum L.) cultivation all over the world. The recessive gene er1, first described over 60 years ago, is well known in pea breeding, as it still maintains its efficiency as a powdery mildew
resistance source. Genetic and phytopathological features of er1 resistance are similar to those of barley, Arabidopsis, and tomato mlo powdery mildew resistance, which is caused by the loss of function of specific members of the MLO gene family. Here, we describe the obtainment of a novel er1 resistant line by experimental mutagenesis with the alkylating agent diethyl sulfate. This line was found to carry a single
nucleotide polymorphism in the PsMLO1 gene sequence, predicted to result in premature termination of translation and a non-functional protein. A cleaved amplified
polymorphic sequence (CAPS) marker was developed on the mutation site and shown to be fully co-segregating with resistance
in F2 individuals. Sequencing of PsMLO1 from three powdery mildew resistant cultivars also revealed the presence of loss-of-function mutations. Taken together, results
reported in this study strongly indicate the identity between er1 and mlo resistances and are expected to be of great breeding importance for the development of resistant cultivars via marker-assisted
selection. 相似文献
88.
Luigi Busetto Fabio Marchetti Stefano Zacchini Valerio Zanotti 《Inorganica chimica acta》2005,358(4):1204-1216
Acetonitrile is easily displaced from [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)(MeCN)(Cp)2][SO3CF3] (R = 2,6-Me2C6H3 (Xyl) (1a); Me (1b)) upon stirring in THF at room temperature in the presence of [NBu4][SCN]. The resulting complexes trans-[Fe2{μ-CN(Me)(R)}(μ-CO)(CO)(NCS)(Cp)2] (R = Xyl (trans-2a); Me (trans-2b)) are completely isomerised to cis-[Fe2{μ-CN(Me)(R)}(μ-CO)(CO)(NCS)(Cp)2] (R = Xyl (cis-2a); Me (cis-2b)) when heated at reflux temperature. Similarly, the complexes cis-[M2{μ-CN(Me)(R)}(μ-CO)(CO)(NCO)(Cp)2] (M = Fe, R = Me (4a); M = Ru, R = Xyl (4b); M = Ru, R = Me (4c)) and cis-[M2{μ-CN(Me)(R)}(μ-CO)(CO)(N3)(Cp)2] (M = Fe, R = Xyl (5a); M = Fe, R = Me (5b); M = Ru, R = Xyl (5c)) can be obtained by heating at reflux temperature a THF solution of [M2{μ-CN(Me)(R)}(μ-CO)(CO)(MeCN)(Cp)2][SO3CF3] (M = Fe, R = Xyl (1a); M = Fe, Me (1b); M = Ru, R = Xyl (1c); M = Ru, R = Me (1d)) in the presence of NaNCO and NaN3, respectively. The reactions of 5 with MeO2CCCCO2Me, HCCCO2Me and (NC)(H)CC(H)(CN) afford the triazolato complexes [M2{μ-CN(Me)(R)}(μ-CO)(CO){N3C2(CO2Me)2}(Cp)2] (M = Fe, R = Xyl (6a); M = Fe, R = Me (6b); M = Ru, R = Xyl (6c)), [M2{μ-CN(Me)(R)}(μ- CO)(CO){N3C2(H)(CO2Me)}(Cp)2] (M = Fe, R = Me (7a); M = Ru, R = Xyl (7b)) and [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){N3C2(H)(CN)}(Cp)2] (8), respectively. The asymmetrically substituted triazolato complexes 7-8 are obtained as mixtures of N(1) and N(2) bonded isomers, whereas 6 exists only in the N(2) form. Methylation of 6-8 results in the formation of the triazole complexes [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){N3(Me)C2(CO2Me)2}(Cp)2][CF3SO3] (9), [M2{μ-CN(Me)(R)}(μ-CO)(CO){N3(Me)C2(H)(CO2Me)}(Cp)2][CF3SO3] (M = Fe, R = Me (10a); M = Ru, R = Xyl (10b)) and [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){N3(Me)C2(H)(CN)}(Cp)2][CF3SO3], 11. The crystal structures of trans-2b, 4b · CH2Cl2, 5a, 6b · 0.5CH2Cl2 and 8 · CH2Cl2 have been determined. 相似文献
89.
Stefano G. A. Draisma Enric Ballesteros Florence Rousseau Thierry Thibaut 《Journal of phycology》2010,46(6):1329-1345
Phylogenetic relationships in the Sargassaceae were explored using three DNA markers, and the monophyly of its genera was challenged. Nineteen out of 24 currently recognized genera were sampled, representing 63 species. The variable mt23S‐tRNA Val intergenic spacer could only be aligned within genera and could not be used to infer intergeneric relationships. The partial mt23S was also useful to delineate genera and was alignable at the family level but provided few informative characters. Analysis of mt23S DNA sequences together with chloroplast‐encoded psbA sequences resulted in a better resolved phylogeny. Hormophysa was the first genus to branch off within the Sargassaceae, followed by Myriodesma; then the three genera Caulocystis, Carpoglossum, and Scaberia in unresolved order; and then Acrocarpia. The other taxa studied here were divided over three major clades, but there was no branch support for the monophyly of two of these. The genera Bifurcaria, Cystoseira, Halidrys, and Sargassum appeared polyphyletic. The following taxonomic changes are proposed: a new genus Brassicophycus for Bifurcaria brassicaeformis (Kützing) E. S. Barton; reinstatement of the genus Sargassopsis for Sargassum decurrens (R. Brown ex Turner) C. Agardh; reinstatement of the genus Sirophysalis for Indo‐Pacific Cystoseira trinodis (Forsskål) C. Agardh; reinstatement of the genus Polycladia for the western Indian Ocean species Cystoseira indica (Thivy et Doshi) Mairh, Cystoseira myrica (S. G. Gmelin) C. Agardh, and Acystis heinii Schiffner; and reinstatement of the genus Stephanocystis for the North Pacific Cystoseira species and Halidrys dioica N. L. Gardner. The European Cystoseira species should be split into three genera, but no name changes are proposed yet, because diagnostic characters were found only for the clade including the type species. Some evolutionary trends could be discerned from the mt23S + psbA phylogeny. 相似文献
90.
Effects on interfacial properties and cell adhesion of surface modification by pectic hairy regions 总被引:1,自引:0,他引:1
Morra M Cassinelli C Cascardo G Nagel MD Della Volpe C Siboni S Maniglio D Brugnara M Ceccone G Schols HA Ulvskov P 《Biomacromolecules》2004,5(6):2094-2104
Polystyrene Petri dishes, aminated by a plasma deposition process, were surface modified by the covalent linking of two different enzymatically modified hairy regions (HRs) from pectin containing, for example, rhamnogalacturonan-I and xylogalacturonan structural elements. The two polysaccharide preparations share the same structural elements of apple pectin, but the relative amounts and lengths of the neutral side chains present differ. Surface analysis by X-ray photoelectron spectroscopy, contact angle measurement, and atomic force microscope (AFM) force-separation curves was used to characterize the effects on surface chemistry and interfacial forces of the surface modification process. Cell adhesion experiments using continuous L-929 fibroblasts and primary aortic smooth muscle cells were performed to evaluate the effect of the polysaccharide nature on cell adhesion. Results show that immobilization of the HR affects the interfacial field of forces and the cell behavior: "equilibrium" contact angles, obtained by a recently introduced vibrational approach, decrease after HR immobilization reaching a value close to 20 degrees . AFM force-separation curves show a more extended (or softer) interface in the case of the HR bearing longer side chains. Accordingly, depending on the HR preparation, cells shifted from spread morphology and adhesion behavior quantitatively comparable to that observed on conventional tissue culture polystyrene to rounded morphology and significantly lower adhesion. These data show that engineering of plant pectins can be a valuable tool to prepare novel and finely tuned polysaccharides having different chemico-physical and biological properties, to be used in the surface modification of medical devices and materials. 相似文献