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1.
Cancer Immunol Immunother ; 73(2): 21, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279995

RESUMO

On August 30, 2023, experts from Germany and abroad met to discuss the successes and challenges of cytokine-induced killer cell (CIK) therapy, that recently celebrated its 30th anniversary providing treatment for cancer. This first virtual conference was hosted by CIO Bonn, a certified Comprehensive Cancer Center (CCC) funded by German Cancer Aid (DKH). In addition to keynote speakers involved in CIK cell clinical trials or optimized preclinical models to improve this adoptive cell immunotherapy, more than 100 attendees from around the world also participated in this event. Initiatives to establish the International Society of CIK Cells (ISCC) and a stronger CIK cell network guiding preclinical research and future clinical trials were also announced.


Assuntos
Células Matadoras Induzidas por Citocinas , Neoplasias , Humanos , Imunoterapia Adotiva , Neoplasias/terapia , Citocinas , Alemanha , Imunoterapia
2.
Metallomics ; 14(7)2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35767875

RESUMO

Zinc is an essential element for human health. Among its many functions, zinc(II) modulates the immune response to infections and, at high concentrations or in the presence of ionophores, inhibits the replication of various RNA viruses. Structural biology studies on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) revealed that zinc(II) is the most common metal ion that binds to viral proteins. However, the number of zinc(II)-binding sites identified by experimental methods is far from exhaustive, as metal ions may be lost during protein purification protocols. To better define the zinc(II)-binding proteome of coronavirus, we leveraged the wealth of deposited structural data and state-of-the-art bioinformatics methods. Through this in silico approach, 15 experimental zinc(II) sites were identified and a further 22 were predicted in Spike, open reading frame (ORF)3a/d, ORF8, and several nonstructural proteins, highlighting an essential role of zinc(II) in viral replication. Furthermore, the structural relationships between viral and eukaryotic sites (typically zinc fingers) indicate that SARS-CoV-2 can compete with human proteins for zinc(II) binding. Given the double-edged effect of zinc(II) ions, both essential and toxic to coronavirus, only the complete elucidation of the structural and regulatory zinc(II)-binding sites can guide selective antiviral strategies based on zinc supplementation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Proteoma , Proteínas Virais , Zinco
3.
Med Phys ; 49(4): 2709-2724, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35134261

RESUMO

PURPOSE: 64 Cu and 67 Cu radioisotopes have nuclear characteristics suitable for nuclear medicine applications. The production of 64 Cu is already well established. However, the production of 67 Cu in quantities suitable to conduct clinical trials is more challenging as it leads to the coproduction of other Cu isotopes, in particular 64 Cu. The aim of this study is to investigate the possibility of using a CuCl2 solution with a mixture of 67/64 Cu radioisotopes for therapeutic purposes, providing an alternative solution for the cyclotron production problem. METHODS: Copper radioisotopes activities were calculated by considering proton beam irradiation of the following targets: (i) 70 Zn in the energy range 70-45 MeV; (ii) 68 Zn in the energy range 70-35 MeV; (iii) a combination of 70 Zn (70-55 MeV) and 68 Zn (55-35 MeV). The contribution of each copper radioisotope to the human-absorbed dose was estimated with OLINDA/EXM software using the biokinetic model for CuCl2 published by ICRP 53. The total absorbed dose generated by the 67/64 CuCl2 mixture, obtained through different production routes, was calculated at different times after the end of the bombardment (EOB). A simple spherical model was used to simulate tumors of different sizes containing uniformly distributed 67/64 Cu mixture and to calculate the absorbed dose of self-irradiation. The biological damage produced by 67 Cu and 64 Cu was also evaluated through cellular dosimetry and cell surviving fraction assessment using the MIRDcell code, considering two prostate cancer cell lines with different radiosensitivity. RESULTS: The absorbed dose to healthy organs and the effective dose (ED) per unit of administered activity of 67 CuCl2 are higher than those of 64 CuCl2 . Absorbed dose values per unit of administered activity of 67/64 CuCl2 mixture increase with time after the EOB because the amount of 67 Cu in the mixture increases. Survival data showed that the biological damage caused per each decay of 67 Cu is greater than that of 64 Cu, assuming that radionuclides remain accumulated in the cell cytoplasm. Sphere model calculations demonstrated that 64 Cu administered activity must be about five times higher than that of 67 Cu to obtain the same absorbed dose for tumor mass between 0.01 and 10 g and about 10 times higher for very small spheres. Consequently, the 64 CuCl2 -absorbed dose to healthy organs will reach higher values than those of 67 CuCl2 . The supplemental activity of the 67/64 CuCl2 mixture, required to get the same tumor-absorbed dose produced by 67 CuCl2 , triggers a dose increment (DI) in healthy organs. The waiting time post-EOB necessary to keep this DI below 10% (t10% ) depends on the irradiation methods employed for the production of the 67/64 CuCl2 mixture. CONCLUSIONS: A mixture of cyclotron produced 67/64 Cu radioisotopes proved to be an alternative solution for the therapeutic use of CuCl2 with minimal DI to healthy organs compared with pure 67 Cu. Irradiation of a 70 Zn+68 Zn target in the 70-35 MeV proton energy range for 185 h appears to be the best option from among all the production routes investigated, as it gives the maximum amount of activity, the shortest t10% (10 h), and less than 1% of 61 Cu and 60 Cu impurities.


Assuntos
Ciclotrons , Neoplasias , Radioisótopos de Cobre , Estudos de Viabilidade , Humanos , Masculino , Neoplasias/tratamento farmacológico , Prótons , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos
6.
Antibiotics (Basel) ; 10(12)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34943662

RESUMO

Plants are considered to be an excellent source of new compounds with antibiotic activity. Carlina acaulis L. is a medicinal plant whose essential oil (EO) is mainly characterized by the polyacetylene carlina oxide, which has antimicrobial properties. The aim of this study was to evaluate the antimicrobial and antifungal activities of C. acaulis EO, carlina oxide, and nanoemulsion (NE) containing the EO. The EO was obtained through plant roots hydrodistillation, and carlina oxide was purified from it through silica gel column chromatography. The NE containing C. acaulis EO was prepared with the high-pressure homogenization method, and the minimum inhibitory concentration (MIC) was determined against several bacterial and fungal strains for all the C. acaulis-derived products. The latter resulted active versus all the screened Gram-positive bacterial strains and also on all the fungal strains with low MIC values. For yeast, the EO and carlina oxide showed good MIC values. The EO-NE demonstrated a better activity than the pure EO on all the tested bacterial and fungal strains. The results suggest that C. acaulis-derived products could be potential candidates for the development of natural antibacterial and antifungal agents.

7.
Biomedicines ; 9(5)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922200

RESUMO

Berberine, the main bioactive component of many medicinal plants belonging to various genera such as Berberis, Coptis, and Hydrastis is a multifunctional compound. Among the numerous interesting biological properties of berberine is broad antimicrobial activity including a range of Gram-positive and Gram-negative bacteria. With the aim of identifying berberine analogues possibly endowed with higher lead-likeness and easier synthetic access, the molecular simplification approach was applied to the secondary metabolite and a series of analogues were prepared and screened for their antimicrobial activity against Gram-positive and Gram-negative bacterial test species. Rewardingly, the berberine simplified analogues displayed 2-20-fold higher potency with respect to berberine. Since our berberine simplified analogues may be easily synthesized and are characterized by lower molecular weight than the parent compound, they are further functionalizable and should be more suitable for oral administration. Molecular docking simulations suggested FtsZ, a well-known protein involved in bacterial cell division, as a possible target.

8.
Pharmacol Rep ; 73(1): 172-184, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33074530

RESUMO

BACKGROUND: Lubeluzole, a neuroprotective anti-ischemic drug, was tested for its ability to act as both antibiotic chemosensitizing and antipropulsive agent for the treatment of infectious diarrhea. METHODS: In the present report, the effect of lubeluzole against antidiarrheal target was tested. The antimicrobial activity towards Gram-positive and Gram-negative bacteria was investigated together with its ability to affect ileum and colon contractility. RESULTS: Concerning the antimicrobial activity, lubeluzole showed synergistic effects when used in combination with minocycline against four common Gram-positive and Gram-negative bacteria (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922), although relatively high doses of lubeluzole were required. In ex vivo experiments on sections of gut smooth muscles, lubeluzole reduced the intestinal contractility in a dose-dependent manner, with greater effects observed on colon than on ileum, and being more potent than reference compounds otilonium bromide and loperamide. CONCLUSION: All above results identify lubeluzole as a possible starting compound for the development of a novel class of antibacterial adjuvants endowed with spasmolytic activity.


Assuntos
Antidiarreicos/uso terapêutico , Diarreia/tratamento farmacológico , Piperidinas/uso terapêutico , Tiazóis/uso terapêutico , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Colo/fisiopatologia , Diarreia/microbiologia , Diarreia/fisiopatologia , Relação Dose-Resposta a Droga , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Cobaias , Íleo/fisiopatologia , Loperamida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Contração Muscular/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Compostos de Amônio Quaternário/uso terapêutico , Ratos , Ratos Sprague-Dawley
9.
PLoS One ; 13(8): e0200902, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30067803

RESUMO

Mentha piperita L. essential oil (EO) is employed for external use as antipruritic, astringent, rubefacient and antiseptic. Several studies demonstrated its significant antiviral, antifungal and antibacterial properties. The aim of this work is the study of the synergistic effects of M. piperita EO with antibacterials and antifungals that are widely available and currently prescribed in therapies against infections. The observed strong synergy may constitute a potential new approach to counter the increasing phenomenon of multidrug resistant bacteria and fungi. In vitro efficacy of the association M. piperita EO/drugs was evaluated against a large panel of Gram-positive and Gram-negative bacteria and yeast strains. The antimicrobial effects were studied by checkerboard microdilution method. The synergistic effect of M. piperita EO with gentamicin resulted in a strong growth inhibition for all the bacterial species under study. The synergistic effect observed for M. piperita EO and antifungals was less pronounced.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Mentha piperita , Óleos de Plantas/farmacologia , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana
10.
Bioinformatics ; 32(18): 2850-2, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27273670

RESUMO

MOTIVATION: The prediction of the iron-sulfur proteome is highly desirable for biomedical and biological research but a freely available tool to predict iron-sulfur proteins has not been developed yet. RESULTS: We developed a web server to predict iron-sulfur proteins from protein sequence(s). This tool, called MetalPredator, is able to process complete proteomes rapidly with high recall and precision. AVAILABILITY AND IMPLEMENTATION: The web server is freely available at: http://metalweb.cerm.unifi.it/tools/metalpredator/ CONTACT: andreini@cerm.unifi.it SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Ferro , Proteoma , Software , Enxofre , Sequência de Aminoácidos , Previsões , Internet
11.
Anticancer Agents Med Chem ; 14(10): 1397-1401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25173557

RESUMO

Hyperforin is a natural phloroglucinol that has been know for the treatment of depression. Hyperforin displays also antibacterial, antiproliferant and antiangiogenic activity. Synthetic derivatives of hyperforin have also recently been reported to possess increased bioactivity. The clinical applications are limited by the hydrophobic characteristics and the instability of the molecule. In this review we discuss about some of the derivatives of hyperforin (aristoforin, tetrahydrohyperforin and octahydrohyperforin) that demonstrated promising antitumor activity. Among these, octahydrohyperforin also possesses antibacterial activity against both the planktonic and biofilm states of bacteria.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Floroglucinol/análogos & derivados , Terpenos/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Hypericum/química , Floroglucinol/farmacologia , Fármacos Fotossensibilizantes/farmacologia
12.
Small ; 10(12): 2476-86, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24619736

RESUMO

Diagnostic approaches based on multimodal imaging are needed for accurate selection of the therapeutic regimens in several diseases, although the dose of administered contrast drugs must be reduced to minimize side effects. Therefore, large efforts are deployed in the development of multimodal contrast agents (MCAs) that permit the complementary visualization of the same diseased area with different sensitivity and different spatial resolution by applying multiple diagnostic techniques. Ideally, MCAs should also allow imaging of diseased tissues with high spatial resolution during surgical interventions. Here a new system based on multifunctional Au-Fe alloy nanoparticles designed to satisfy the main requirements of an ideal MCA is reported and their biocompatibility and imaging capability are described. The MCAs show easy and versatile surface conjugation with thiolated molecules, magnetic resonance imaging (MRI) and computed X-ray tomography (CT) signals for anatomical and physiological information (i.e., diagnostic and prognostic imaging), large Raman signals amplified by surface enhanced Raman scattering (SERS) for high sensitivity and high resolution intrasurgical imaging, biocompatibility, exploitability for in vivo use and capability of selective accumulation in tumors by enhanced permeability and retention effect. Taken together, these results show that Au-Fe nanoalloys are excellent candidates as multimodal MRI-CT-SERS imaging agents.


Assuntos
Ligas de Ouro/síntese química , Compostos de Ferro/síntese química , Imageamento por Ressonância Magnética/instrumentação , Nanopartículas de Magnetita/química , Imagem Multimodal/instrumentação , Análise Espectral Raman/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Animais , Células Cultivadas , Meios de Contraste/síntese química , Meios de Contraste/química , Ligas de Ouro/química , Humanos , Compostos de Ferro/química , Imageamento por Ressonância Magnética/métodos , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Monitorização Intraoperatória/instrumentação , Monitorização Intraoperatória/métodos , Imagem Multimodal/métodos , Análise Espectral Raman/métodos , Tomografia Computadorizada por Raios X/métodos , Células U937
13.
J Nat Prod ; 76(9): 1819-23, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-23981190

RESUMO

Bacterial biofilms are organized communities of microorganisms, embedded in a self-produced matrix, growing on a biotic surface and resistant to many antimicrobial agents when associated with a medical device. These biofilms require the development of new strategies for the prevention and treatment of infectious disease, including the potential use of natural products. One interesting natural product example is Hypericum, a plant genus that contains species known to have antimicrobial properties. The major constituent of Hypericum perforatum is an unstable compound named hyperforin (1); for this reason it was not believed to play a significant role in the pharmacological effects. In this investigation a hydrogenated hyperforin analogue (2) was tested on several ATCC and clinical isolate strains, in their planktonic and biofilm form (Staphylococcus aureus, MRSA, and Enterococcus faecalis). Compound 2 was effective against planktonic and biofilm cultures, probably due to higher stability, showing the percentage of cells killed in the range from 45% to 52%. These results are noteworthy from the point of view of future development of these polyprenylated phloroglucinols as potential antibiotics.


Assuntos
Biofilmes/efeitos dos fármacos , Floroglucinol/análogos & derivados , Terpenos/farmacologia , Biofilmes/crescimento & desenvolvimento , Enterococcus faecalis/efeitos dos fármacos , Hypericum/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Floroglucinol/farmacologia , Staphylococcus aureus/efeitos dos fármacos
14.
Endocr Relat Cancer ; 19(4): 527-39, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22673336

RESUMO

Treatment options are insufficient in patients with adrenocortical carcinoma (ACC). Based on the efficacy of sorafenib, a tyrosine kinase inhibitor, and everolimus, an inhibitor of the mammalian target of rapamycin in tumors of different histotype, we aimed at testing these drugs in adrenocortical cancer models. The expression of vascular endothelial growth factor and its receptors (VEGFR1-2) was studied in 18 ACCs, 33 aldosterone-producing adenomas, 12 cortisol-producing adenomas, and six normal adrenal cortex by real-time PCR and immunohistochemistry and by immunoblotting in SW13 and H295R cancer cell lines. The effects of sorafenib and everolimus, alone or in combination, were tested on primary adrenocortical cultures and SW13 and H295R cells by evaluating cell viability and apoptosis in vitro and tumor growth inhibition of tumor cell line xenografts in immunodeficient mice in vivo. VEGF and VEGFR1-2 were detected in all samples and appeared over-expressed in two-thirds of ACC specimens. Dose-dependent inhibition of cell viability was observed particularly in SW13 cells after 24 h treatment with either drug; drug combination produced markedly synergistic growth inhibition. Increasing apoptosis was observed in tumor cells treated with the drugs, particularly with sorafenib. Finally, a significant mass reduction and increased survival were observed in SW13 xenograft model undergoing treatment with the drugs in combination. Our data suggest that an autocrine VEGF loop may exist within ACC. Furthermore, a combination of molecularly targeted agents may have both antiangiogenic and direct antitumor effects and thus could represent a new therapeutic tool for the treatment of ACC.


Assuntos
Adenoma/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzenossulfonatos/administração & dosagem , Piridinas/administração & dosagem , Sirolimo/análogos & derivados , Adenoma/patologia , Adolescente , Neoplasias do Córtex Suprarrenal/patologia , Adulto , Idoso , Animais , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Linhagem Celular Tumoral , Criança , Pré-Escolar , Everolimo , Feminino , Humanos , Lactente , Masculino , Camundongos , Camundongos Knockout , Camundongos SCID , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Compostos de Fenilureia , Sirolimo/administração & dosagem , Sorafenibe , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
15.
Phytomedicine ; 16(10): 972-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19616925

RESUMO

In this study we investigated a synergistic effect between the essential oils Origanum vulgare, Pelargonium graveolens and Melaleuca alternifolia and the antifungal compound Nystatin. Nystatin is considered a drug of choice in the treatment of fungal infections, but it can cause some considerable problems through its side effects, such as renal damage. Finding a new product that can reduce the Nystatin dose via combination is very important. Our findings showed an experimental occurrence of a synergistic interaction between two of these essential oils and Nystatin. The essential oil O. vulgare appeared to be the most effective, inhibiting all the Candida species evaluated in this study. Some combinations of Nystatin and P. graveolens essential oil did not have any synergistic interactions for some of the strains considered. Associations of Nystatin with M. alternifolia essential oil had only an additive effect.


Assuntos
Candida/efeitos dos fármacos , Melaleuca/química , Nistatina/farmacologia , Óleos Voláteis/farmacologia , Origanum/química , Pelargonium/química , Antifúngicos/análise , Antifúngicos/farmacologia , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana
16.
Phytomedicine ; 15(8): 635-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18579358

RESUMO

In this work we highlight a possible synergistic anti-Candida effect between Melaleuca alternifolia, Origanum vulgare and Pelargonium graveolens essential oils and the antifungal compound Amphotericin B. The antifungal activity was assessed using the agar dilution method in eleven Candida strains. The results obtained indicate the occurrence of a synergistic interaction between the essential oils under study and Amphotericin B. P. graveolens essential oil appeared to be the most effective, inhibiting all the Candida species evaluated by this study.


Assuntos
Anfotericina B/farmacologia , Candida/efeitos dos fármacos , Óleos Voláteis/farmacologia , Pelargonium/química , Óleo de Melaleuca/farmacologia , Animais , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleo de Melaleuca/química
17.
Phytomedicine ; 14(11): 727-32, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17303397

RESUMO

UNLABELLED: The objective of the present study was that of verifying a possible synergistic antibacterial effect between Pelargonium graveolens [Lis-Balchin, M., Deans, S.G., Hart, S., 1996. Bioactive Geranium oils from different commercial sources. J. Essential Oil Res. 8, 281-290.] essential oil (and its main components) and Norfloxacin antibiotic. As a first step growth inhibition by some types of essential oils was assessed in five microbial species. The antimicrobial effects of P. graveolens oil, as well as those of its components, were evaluated by means of the agar dilution method (ADM) against Bacillus cereus ATCC 11778, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 35218, Staphylococcus aureus ATCC 6538 and S. aureus ATCC 29213. The results obtained highlighted the occurrence of a pronounced synergism between P. graveolens essential oil and Norfloxacin against three of the five bacterial species under study with a FIC index in the 0.37-0.50 range. Such antibacterial effects were also shown to increase, although to a lesser extent, when Norfloxacin was given with the main components of P. graveolens essential oil. SIGNIFICANCE AND IMPACT OF THE STUDY: The combination of Norfloxacin with either P. graveolens essential oil, or with some of the main components of this latter, in the treatment of infections caused by some bacterial species is likely to reduce the minimum effective dose of Norfloxacin thus minimizing the side effects of the antibiotic.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Norfloxacino/farmacologia , Pelargonium , Fitoterapia , Óleos de Plantas/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Testes de Sensibilidade Microbiana , Norfloxacino/administração & dosagem , Norfloxacino/uso terapêutico , Óleos de Plantas/administração & dosagem , Óleos de Plantas/uso terapêutico
18.
Phytother Res ; 20(6): 454-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16619355

RESUMO

The antimicrobial activity of saponins from Medicago sativa, M. arborea and M. arabica against a selection of medically important yeasts, Gram-positive and -negative bacteria was investigated. Structure-activity growth inhibitory effects of related prosapogenins and sapogenins are also described. Increasing antibiotic activity was observed going from the saponin extracts to the sapogenin samples, suggesting that the sugar moiety is not important for the antimicrobial efficacy. Activity was especially high against Gram-positive bacteria (Bacillus cereus, B. subtilis, Staphylococcus aureus and Enterococcus faecalis) with M. arabica being the species showing a broader spectrum of action. Discrete antifungal activity was also observed, mainly against Saccharomyces cerevisiae. The observed antimicrobial properties of M. sativa and M. arborea were related to the content of medicagenic acid, while hederagenin seems to contribute to the bioactivity of M. arabica total sapogenins.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Medicago/química , Saponinas/farmacologia , Antibacterianos/análise , Antifúngicos/análise , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Sapogeninas/isolamento & purificação , Saponinas/análise , Relação Estrutura-Atividade
19.
Bioinformatics ; 20(9): 1373-80, 2004 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-14962940

RESUMO

MOTIVATION: With the advent of genome sequencing, a huge database of protein primary sequences has been accumulating. In parallel, a number of tools to investigate and expand upon this information, e.g. reconstructing and building relationships between protein families and superfamilies, have been developed. Metalloproteins are proteins capable of binding one or more metal ions, which are required for their biological function or for regulation of their activities or for structural purposes. Sometimes, metal binding can be observed in vitro but not be physiologically relevant. At present, there is a lack of specific tools to address the matter of the identification of metalloproteins in databases of gene sequences. RESULTS: In the present work, an approach exploiting metal-binding patterns (MBPs) of metalloproteins present in the Protein Data Bank to search gene banks for new metalloproteins is presented and applied to copper proteins. Nearly 100 different MBPs have been identified and then used for subsequent applications. The ensemble of sequences of the whole PDB is used to assess the potentiality and limits of the method and to identify levels of confidence for the predictions output by the search. It appears that copper-binding capabilities are identified with a confidence >90% when the percentage of identical amino acids aligned around the MBP by PHI-BLAST is at least 20% with respect to the entire protein domain length. If this percentage is between 10% and 20%, the level of confidence is approximately 50%. Application of the methodology to the entire genome sequences of Pyrococcus furiosus, Escherichia coli, Drosophila melanogaster and Homo sapiens suggests some differentiation between prokaryotes and eukaryotes. SUPPLEMENTARY INFORMATION: A table reporting statistics on the MBP identified; a list of all hits retrieved for the four organisms considered; a figure showing the number of hits for the four organisms as a function of I(d)(Global).


Assuntos
Algoritmos , Cobre/química , Bases de Dados de Proteínas , Metaloproteínas/química , Mapeamento de Interação de Proteínas/métodos , Alinhamento de Sequência/métodos , Análise de Sequência de Proteína/métodos , Sítios de Ligação , Cobre/análise , Proteínas de Drosophila/química , Genômica/métodos , Humanos , Armazenamento e Recuperação da Informação/métodos , Metaloproteínas/análise , Metaloproteínas/classificação , Ligação Proteica , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
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