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1.
Int. microbiol ; 26(4): 869-880, Nov. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-227476

RESUMO

A group of biosurfactants are lipopeptides that are produced by some microorganisms, especially Bacillus strains. They are new bioactive agents with anticancer, antibacterial, antifungal, and antiviral activities. Also, they are used in sanitation industries. In this study, a lead-resistant strain of Bacillus halotolerans was isolated for lipopeptide production. This isolate exhibited metal resistance (lead, calcium, chromium, nickel, copper, manganese, and mercury), salt tolerance (12%), and antimicrobial activities against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Saccharomyces cerevisiae. The production of lipopeptide was optimized, concentrated, and then extracted from the polyacrylamide gel in a simple way for the first time. The nature of the purified lipopeptide was determined by FTIR, GC/MS, and HPLC analyses. The purified lipopeptide indicated significant antioxidant properties (90.38% at a concentration of 0.8 mg ml−1). Also, it had anticancer activity by apoptosis (flow cytometry analysis) in MCF-7 cells, while it had no cytotoxicity on HEK-293 normal cells. Therefore, Bacillus halotolerans lipopeptide has the potential to be used as an antioxidant, antimicrobial, or anticancer agent in the medical and food industries.(AU)


Assuntos
Humanos , Bacillus , Lipopeptídeos , Antioxidantes , Citometria de Fluxo , Microbiologia , Técnicas Microbiológicas
2.
Int. microbiol ; 26(4): 907-915, Nov. 2023. graf
Artigo em Inglês | IBECS | ID: ibc-227479

RESUMO

The prevention of biofilm formation plays a pivotal role in managing Helicobacter pylori inside the body and the environment. This study showed in vitro potentials of two recently isolated probiotic strains, Bacillus sp. 1630F and Enterococcus sp. 7C37, to form biofilm and combat H. pylori attachment to the abiotic and biotic surfaces. Lactobacillus casei and Bifidobacterium bifidum were used as the reference probiotics. The biofilm rates were the highest in the solid–liquid interface for Lactobacillus and Bifidobacterium and the air–liquid interface for Bacillus and Enterococcus. The highest tolerances to the environmental conditions were observed during the biofilm formations of Enterococcus and Bifidobacterium (pH), Enterococcus and Bacillus (bile), and Bifidobacterium and Lactobacillus (NaCl) on the polystyrene and glass substratum, respectively. Biofilms occurred more quickly by Bacillus and Enterococcus strains than reference strains on the polystyrene and glass substratum, respectively. Enterococcus (competition) and Bacillus (exclusion) achieved the most inhibition of H. pylori biofilm formations on the polystyrene and AGS cells, respectively. Expression of luxS was promoted by Bacillus (exclusion, 3.2 fold) and Enterococcus (competition, 2.0 fold). Expression of ropD was decreased when H. pylori biofilm was excluded by Bacillus (0.4 fold) and Enterococcus (0.2 fold) cells. This study demonstrated the ability of Bacillus and Enterococcus probiotic bacteria to form biofilm and combat H. pylori biofilm formation.(AU)


Assuntos
Humanos , Bacillus , Enterococcus , Helicobacter pylori , Probióticos , Poliestirenos , Biofilmes , Microbiologia , Técnicas Microbiológicas , Infecções por Bifidobacteriales
3.
Int. microbiol ; 26(3): 487-500, Ene-Agos, 2023.
Artigo em Inglês | IBECS | ID: ibc-223976

RESUMO

Mustard-rapeseed cultivation is affected by Sclerotinia sclerotiorum resulting in loss of oil yield and degradation of crop quality. This study adopted an environment friendly biocontrol approach of screening mustard endophytes against the pathogen. Two bacterial isolates, Bacillus safensis (TS46 bac4) and Bacillus australimaris (SM2) showed potential biocontrol activity under both in vitro and in vivo conditions. Dual culture assay reported 90% inhibition of fungal growth. The bacterial cell free supernatant of isolate SM2 showed 52.89% inhibition and the other isolate TS46 bac4 showed 57.97% inhibition. The crude (10 mg/ml) and purified (10 mg/ml) metabolite extract of SM2 showed 100% and 97% inhibition respectively. Both crude (10 mg/ml) and purified (7.5 mg/ml) metabolite extract of TS46 bac4 exhibited 99% inhibition of the pathogen. Antifungal lipopeptides: surfactin, iturin and fengycin were identified in bacterial metabolite extract of the isolates. Both strains promoted healthy germination and prevented the formation of any disease symptoms in seedling. The selected Bacillus strains applied by spray method showed better results against fungal infection on mustard leaf and stem. Microscopic studies revealed degradation of fungal mycelial growth by both isolates. These findings support the employment of the bacterial strains as potential biocontrol agents to reduce the effects of S. sclerotiorum in mustard-rapeseed.(AU)


Assuntos
Humanos , Mostardeira/virologia , Endófitos , Ascomicetos , Antifúngicos , Bacillus , Microbiologia , Técnicas Microbiológicas
4.
An. R. Acad. Nac. Farm. (Internet) ; 88(número extraordinario): 27-34, diciembre 2022.
Artigo em Espanhol | IBECS | ID: ibc-225739

RESUMO

Introducción: En el agua de los ecosistemas acuáticos considerados extremos, debido a los valores de sus parámetros fisicoquímicos y químicos, tales como altas concentraciones de sales, ambientes oligotróficos, pH extremos, alta radiación y temperaturas extremas, existe una población bacteriana que se ha adaptado a esas condiciones y que pueden ser un reservorio importante de resistomas naturales.Objetivo. Conocer los perfiles de susceptibilidad a diversos antibióticos en cepas del género Bacillus aisladas de balnearios de aguas mineromedicinales y de agua de un lago cratérico volcánico del Ecuador.Materiales y métodos. Se analizaron un total de 16 muestras de agua mineromedicinal y 32 muestras de agua de lago cratérico volcánico. El aislamiento de Bacillus se realizó por la técnica de filtración en membrana, utilizando filtros Millipore de 0,45 μm de poro, un volumen de muestra de 100 mL y el agar R2A. Las cepas aisladas se identificaron siguiendo los esquemas de MacFaddin (2004), complementadas con las pruebas bioquímicas de las galerías Microgen para Bacillus. El perfil de resistencia a los antibióticos se determinó por el método de difusión en placas de Kirby y Bauer (1966) interpretándose según el CLSI (2019).Resultados. Se identificaron 19 cepas de Bacillus. La mayoría de las cepas fueron resistentes y multiresistentes a los antibióticos clindamicina, eritromicina, gentamicina, oxacilina y penicilina.Conclusiones. Los resultados señalan la presencia de especies de Bacillus y de resistomas asociados a este género en el agua de ambientes naturales extremos en el Ecuador, lo cual sugiere que estos ambientes pueden ser un reservorio importante de bacterias resistentes a los antibióticos. (AU)


Introduction: The water of aquatic ecosystems considered extreme, given the values of its physicochemical and chemical parameters, such as high concentrations of salts, oligotrophic environments, extreme pH, high radiation and extreme temperatures, there is a bacterial population that has adapted to these conditions and that they can be an important reservoir of natural resistomes.Objective. The objective of the present work was to know the profiles of susceptibility to various antibiotics in strains of the Bacillus genus isolated from mineromedicinal water spas and water from a volcanic crater lake in Ecuador.Materials and methods. A total of 16 mineromedicinal water samples and 32 samples of crater volcanic lake water were analyzed. The isolation of the Bacillus colonies was carried out by the membrane filtration technique, using Millipore filters of 0.45 μm pore, a sample volume of 100 mL and R2A agar. The isolated strains were identified following the schemes of MacFaddin (2004), complemented with the biochemical tests of the Microgen galleries for Bacillus. The antibiotic resistance profile was determined by the plate diffusion method of Kirby and Bauer (1966), interpreted according to the CLSI (2019).Results. 19 Bacillus strains were identified. Most of the strains were resistant and multi-resistant to the antibiotic clindamycin, erythromycin, gentamicin, oxacillin, and penicillin. Conclusions. The results indicate the presence of Bacillus species and resistomes associated with this genus in the water of extreme natural environments in Ecuador, which suggests that these environments may be an important reservoir of bacteria resistant to antibiotics. (AU)


Assuntos
Humanos , Ambientes Extremos , Bacillus , Resistência Microbiana a Medicamentos , Antibacterianos
5.
Int. microbiol ; 25(4): 839-850, Nov. 2022. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-216250

RESUMO

Two dozen field-collected Bacillus and a dozen Bacillus spizizenii wild-type strains from strain collections were selected on the basis of their antagonistic properties against the Gram-positive strain Micrococcus luteus. Based on their genetic and antibiotic profiles, they were characterized (subtilin encoding spaS gene sequences, mass spectrometric, and quantitative-reversed phase liquid chromatographic analyses, as well as the presence of the lanthionine cyclase protein SpaC by western blotting), seven novel producers of the lanthipeptide subtilin. Phylogenetic analyses of the subtilin-producing wild-type strains based on their 16S rRNA sequences showed that all seven strains could be classified as B. spizizenii: The field-collected strains HS and N5, as well as strains DSM 618, 1087, 6395, 6405, and 8439 from the German Collection of Microorganisms and Cell Cultures. To the best of our knowledge, all B. spizizenii strains described so far are characterized by the fact that they can produce a lanthipeptide of the subtilin family. Both the lanthipeptide structures and the organization and sequences of the 16S rRNA-encoding genes suggest a subdivision of B. spizizenii into subspecies: The subtilin-producing B. spizizenii strains are distinctly different from the entianin-producing B. spizizenii typing strain TU-B-10 T (DSM 15029 T).(AU)


Assuntos
Humanos , Bacillus , Antibacterianos , Microbiologia
6.
Int. microbiol ; 25(2): 353-363, May. 2022. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-216037

RESUMO

The effect of oxygen on the germination and culturability of aerobic Bacillus atrophaeus spores was investigated in this study. Under oxic or anoxic conditions, various nutritional and non-nutritional germinants were utilized to induce germination. Tb3+-dipicolinic acid fluorescence assay and phase-contrast microscopy were used to track the germination process. The final germination level, germination half time, and germination speed were used to define germination kinetics. Colony-forming unit enumeration was used to assess the culturability of germinated spores germinated with or without oxygen. The results show that in the absence of oxygen, the final germination level was unaffected, germination half time decreased by up to 35.0%, germination speed increased by up to 27.4%, and culturability decreased by up to 95.1%. It is suggested that oxygen affects some germinant receptor-dependent germination pathways, implying that biomolecules engaged in these pathways may be oxygen-sensitive. Furthermore, spores that have completed the germination process in either anoxic or oxic conditions may have different culturability. This research contributed to a better understanding of the fundamental mechanism of germination.(AU)


Assuntos
Oxigênio , Germinação , Bacillus , Fluorescência , Microscopia de Contraste de Fase , Microbiologia
7.
An. R. Acad. Nac. Farm. (Internet) ; 87(1): 27-34, ene.-mar. 2021. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-201632

RESUMO

INTRODUCCIÓN: En el agua de los ecosistemas acuáticos considerados extremos, debido a los valores de sus parámetros fisicoquímicos y químicos, tales como altas concentraciones de sales, ambientes oligotróficos, pH extremos, alta radiación y temperaturas extremas, existe una población bacteriana que se ha adaptado a esas condiciones y que pueden ser un reservorio importante de resistomas naturales. OBJETIVO: Conocer los perfiles de susceptibilidad a diversos antibióticos en cepas del género Bacillus aisladas de balnearios de aguas mineromedicinales y de agua de un lago cratérico volcánico del Ecuador. MATERIALES Y MÉTODOS. Se analizaron un total de 16 muestras de agua mineromedicinal y 32 muestras de agua de lago cratérico volcánico. El aislamiento de Bacillus se realizó por la técnica de filtración en membrana, utilizando filtros Millipore de 0,45 μm de poro, un volumen de muestra de 100 mL y el agar R2A. Las cepas aisladas se identificaron siguiendo los esquemas de MacFaddin (2004), complementadas con las pruebas bioquímicas de las galerías Microgen para Bacillus. El perfil de resistencia a los antibióticos se determinó por el método de difusión en placas de Kirby y Bauer (1966) interpretándose según el CLSI (2019). RESULTADOS: Se identificaron 19 cepas de Bacillus. La mayoría de las cepas fueron resistentes y multiresistentes a los antibióticos clindamicina, eritromicina, gentamicina, oxacilina y penicilina. CONCLUSIONES: Los resultados señalan la presencia de especies de Bacillus y de resistomas asociados a este género en el agua de ambientes naturales extremos en el Ecuador, lo cual sugiere que estos ambientes pueden ser un reservorio importante de bacterias resistentes a los antibióticos


INTRODUCTION: The water of aquatic ecosystems considered extreme, given the values of its physicochemical and chemical parameters, such as high concentrations of salts, oligotrophic environments, extreme pH, high radiation and extreme temperatures, there is a bacterial population that has adapted to these conditions and that they can be an important reservoir of natural resistomes. OBJECTIVE: The objective of the present work was to know the profiles of susceptibility to various antibiotics in strains of the Bacillus genus isolated from mineromedicinal water spas and water from a volcanic crater lake in Ecuador. MATERIALS AND METHODS: A total of 16 mineromedicinal water samples and 32 samples of crater volcanic lake water were analyzed. The isolation of the Bacillus colonies was carried out by the membrane filtration technique, using Millipore filters of 0.45 μm pore, a sample volume of 100 mL and R2A agar. The isolated strains were identified following the schemes of MacFaddin (2004), complemented with the biochemical tests of the Microgen galleries for Bacillus. The antibiotic resistance profile was determined by the plate diffusion method of Kirby and Bauer (1966), interpreted according to the CLSI (2019). RESULTS: 19 Bacillus strains were identified. Most of the strains were resistant and multi-resistant to the antibiotic clindamycin, erythromycin, gentamicin, oxacillin, and penicillin. CONCLUSIONS: The results indicate the presence of Bacillus species and resistomes associated with this genus in the water of extreme natural environments in Ecuador, which suggests that these environments may be an important reservoir of bacteria resistant to antibiotics


Assuntos
Microbiologia da Água , Bacillus/efeitos dos fármacos , Bacillus/isolamento & purificação , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla , Lagos/microbiologia , Piscinas , Equador
8.
Int. microbiol ; 22(1): 29-39, mar. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184811

RESUMO

In a natural ecosystem, various organisms digest and hydrolyze lignocellulose biomass efficiently. Termites are one of them. They digest lignocellulose biomass with the help of symbiotic microorganisms in their gut. Therefore, termites gut may harbor potential sources of microorganisms capable to degrade lignocellulose biomass. In this study, termite gut microbiomes of Cryptotermes brevis species were isolated and identified for their capability to degrade lignin and polysaccharides. Alkali lignin, carboxymethylcellulose, and xylan were used as the only carbon sources in the medium to isolate lignin-, cellulose-, and hemicellulose-degrading bacteria. By this method, two bacteria strains, Bacillus sp. BMP01 and Ochrobactrum oryzae BMP03 strain were isolated and identified. Bacillus sp. BMP01 strain has capabilities to hydrolyze carboxymethylcellulose and xylan to glucose and xylose, respectively. This strain showed high xylanase activity (about 0.21 U/ml) and carboxymethyl cellulase activity (about 0.25 U/ml). The ability to hydrolyze both carboxymethylcellulose and xylan makes it superior to other known cellulolytic bacteria. Ochrobactrum oryzae BMP03 strain showed laccase activity, which indicates its ability to depolymerize lignin. Lignocellulose-degrading bacteria play a vital role in the biological conversion of lignocellulose biomass to biofuel. Overall, this study shows that termite's gut microbiomes are potential sources of lignocellulose-degrading bacteria that can be cultured and used in the biological conversion of lignocellulose biomass to biofuel


No disponible


Assuntos
Animais , Bacillus/isolamento & purificação , Celulose/metabolismo , Intestinos/microbiologia , Isópteros/microbiologia , Lignina/metabolismo , Ochrobactrum/isolamento & purificação , Ochrobactrum/metabolismo , Polissacarídeos/metabolismo , Ração Animal , Bacillus/metabolismo , Glucose/metabolismo , Hidrólise , Madeira , Xilanos/metabolismo , Xilose/metabolismo
9.
Fisioterapia (Madr., Ed. impr.) ; 40(2): 59-64, mar.-abr. 2018. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-171697

RESUMO

Objetivo: Determinar el perfil bacteriológico en superficies de trabajo, aditamentos y equipos del área de Fisioterapia de una institución prestadora de salud de nivel 1 de complejidad en salud de la ciudad de Popayán, Cauca, Colombia, durante el mes de diciembre del 2015. Métodos: Se realizó un estudio descriptivo a partir de la toma de 13 muestras elegidas al azar entre superficies de trabajo, aditamentos y equipos del área de fisioterapia, el aislamiento se realizó a partir de medios de cultivos no selectivos y la identificación bacteriana por técnicas manuales. Resultados: De 13 muestras obtenidas, el 38,5 por mil fueron negativas y el 61,5 por mil fueron positiva, en las cuales en el 53,9 por mil se encontraron estafilococos coagulasa negativa y en el 7,6 por mil se aísla Micrococcus sp. y Bacillus sp. Conclusiones: La desinfección de las superficies de trabajo, aditamentos y equipos debe realizarse con un agente de mayor eficacia y potencia contra bacterias grampositivas, a fin de reducir contaminación de material inertes y posibles infecciones cruzadas


Objective: To determine the bacteriological profile in work areas, fittings, and equipment of the Physiotherapy area of Popayán, Cauca, Colombia. Methods: A descriptive study was performed based on 13 randomly selected samples from work surfaces, fittings, and equipment in the physiotherapy area. The isolation was performed using non-selective culture media, and bacterial identification was by using manual techniques. Results: Of the 13 samples obtained, 38.5 per-mille were negative and 61.5 per-mille were positive, in which 53.9 per-mille were coagulase negative staphylococcus, and 7.6 per-mille isolated Micrococcus sp. and Bacillus sp. Conclusions: Disinfection of work surfaces, fixtures and equipment should be performed with a more effective and potent agent against gram-positive bacteria, in order to reduce contamination of inert material and possible cross-infection


Assuntos
Humanos , Incrustação Biológica , Serviço Hospitalar de Fisioterapia , Modalidades de Fisioterapia , Desinfecção/métodos , Meios de Cultura/isolamento & purificação , Coagulase/análise , Micrococcus/isolamento & purificação , Bacillus/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Infecções por Bactérias Gram-Positivas/terapia , Técnicas Bacteriológicas/métodos
10.
Int. microbiol ; 18(2): 91-97, jun. 2015. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-143386

RESUMO

Entomopathogenic fungi are potential tools to biocontrol cicadellids and delphacids, two groups of insects that cause extensive damage to agricultural crops. However, bacteria living on the host cuticle may inhibit fungal growth. In the present work, following the molecular characterization of 10 strains of Bacillus isolated from the integument of cicadellids and delphacids, we selected isolates of the fungi Beauveria bassiana and Metarhizium anisopliae that are resistant to the antimicrobials secreted by these bacterial strains. The antagonistic activity of the 10 bacterial isolates belonging to the genus Bacillus (i.e., B. amyloliquefaciens, B. pumilus, and B. subtilis) against 41 isolates of Bea. bassiana and 20 isolates of M. anisopliae was investigated in vitro on tryptic soy agar using the central disk test. With this approach, isolates of Bea. bassiana and M. anisopliae resistant to antagonistic bacteria were identified that can be further developed as biological control agents (AU)


No disponible


Assuntos
Animais , Fungos/patogenicidade , Micoses/imunologia , Bacillus/patogenicidade , Doenças das Aves/imunologia , Hemípteros/imunologia , Entomologia/métodos
11.
Rev. toxicol ; 32(2): 107-111, 2015. tab, ilus, graf
Artigo em Inglês | IBECS | ID: ibc-146470

RESUMO

The increments of plant diseases caused by the proliferation of fungicide-resistant pathogens intensified the research of new active metabolites against them. The study of biological methods as an alternative to chemical control has reach relevance in recent years. It has been suggested that the use of metabolites from Bacillus, is an alternative or supplementary method to chemical plant protection, if they are not toxic for the consumers and environmentally friendly. The toxicity of different concentrations of antifungal metabolites produced by Bacillus sp. IBA 33 was evaluated. Their ability to induce cytotoxic effects was investigated by different tests as hemolysis, and Artemia salina and Allium cepa L immobilization. With 2.56 mg/ml of antifungal metabolites hemolysis reached 24.07%, to 1.28 mg/ml was 14%. HC50 was 10.41 mg/ml. A. salina nauplii exposed to 3.2, 1.6 and 0.8 mg/ml of antifungal metabolites showed 80, 20 and 10% of mortality respectively; LD50 was 2.24 mg/ml. In Allium cepa L test after 72 h of treatment, the roots lengths were 8.75, 10.35 and 23.75 mm with 3.2, 1.6 and 0.8 mg/ml of antifungal metabolites respectively. The EC50 was 0.078 mg/ml. After 144 h the EC50 was 4.11 mg/ml. Only with 3.2 mg/ml of metabolites, chromosomal aberrations, cytoplasm vacuolization and decentralization of nuclei were observed in the cells of Allium cepa L. No micronuclei were detected. Under the experimental conditions, the antifungal metabolites concentrations assayed are considered non toxic (AU)


El incremento de enfermedades de plantas causado por la proliferación de patógenos resistentes a fungicidas intensificó la investigación de nuevos metabolitos activos contra ellos. El estudio de métodos biológicos como una alternativa al control químico ha alcanzado relevancia en años recientes. Se ha sugerido que el uso de metabolitos de Bacillus, es una alternativa o un método suplementario a la protección química de las plantas, siempre y cuando ellos no sean tóxicos para los consumidores y sean amigables para el medio ambiente. Se ha evaluado la toxicidad de diferentes concentraciones de metabolitos antifúngicos producidos por Bacillus sp. IBA33. Se investigó su capacidad para inducir efectos citotóxicos mediante diferentes tests como hemólisis e inmovilización de Artemia salina y Allium cepa L. Con 2.56 mg/ml de metabolitos antifúngicos la hemólisis alcanzó 24.07%, para 1.28 mg/ml fue 14%. La HC50 fue 10.41 mg/ml. Nauplios de Artemia salina expuestos a 3.2; 1.6 y 0.8 mg/ml de metabolitos antifúngicos mostraron 80; 20 y 10% de mortalidad respectivamente después de 24 h de tratamiento; la LD50 fue 2.24 mg/ml. En el test de Allium cepaL después de 72 h de tratamiento, la longitud de las raíces fueron 8.75; 10.35 y 23.75 mm con 3.2; 1.6 y 0.8 mg/ml de metabolitos antifúngicos respectivamente, con una EC50 de 0.078 mg/ml. Después de 144 h la EC50 fue 4.11 mg/ml. Solamente con 3.2 mg/ml de metabolitos fueron observadas aberraciones cromosómicas, vacualización y descentralización de los núcleos en las células de Allium cepa L. No se observaron micronúcleos. Bajo las condiciones experimentales, las concentraciones de metabolitos antifúngicos ensayadas son consideradas no tóxicas


Assuntos
Antifúngicos/metabolismo , Antifúngicos/toxicidade , Bacillus/patogenicidade , Plantas/toxicidade , Hemólise , Artemia , 25938/toxicidade , Citotoxicidade Celular Dependente de Anticorpos , Lipopeptídeos/toxicidade , Doenças das Plantas , Antifúngicos/efeitos adversos , Plantas/efeitos adversos , Plantas
12.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 56(1): 51-53, ene.-feb. 2012.
Artigo em Espanhol | IBECS | ID: ibc-96535

RESUMO

Staphylococcus epidermidis (S. epidermidis) es la especie más prevalente de los estafilococos coagulasa negativos (ECN). Supone más del 65% de todos los estafilococos aislados en las muestras. En los últimos años, el protagonismo como patógenos es manifiesto, fundamentalmente causando bacteriemia e infección de material protésico. El linezolid, por ser un antibiótico eficaz frente a este patógeno y ante su facilidad de uso por vía oral, está siendo de elección en el tratamiento de estas infecciones en el domicilio. Sin embargo, el uso continuado de este fármaco está causando la aparición de resistencias. Presentamos el caso clínico de una infección protésica por S. epidermidis resistente a linezolid en un paciente en el que previamente se había aislado Bacillus sp., motivo por el que había recibido este antibiótico durante 16 días. El caso no estuvo relacionado con un brote intrahospitalario de S. epidermidis resistente a linezolid (AU)


Staphylococcus epidermidis is the most prevalent species of coagulase-negative staphylococci (CNS). It accounts for over 65% of all staphylococci isolated from samples. In recent years the increasing relevance of CNS as pathogens is evident, mainly causing bacteraemia and prosthetic device infection. Linezolid, being an effective antibiotic against this pathogen, and due to its ease of use and oral posology, is becoming the treatment of choice in outpatients. However, the continued use of this drug is causing the development of resistant strains. We describe a prosthetic infection due to linezolid resistant S. epidermidis that appeared in a patient who had been previously treated with this drug for 16 days due to the isolation of Bacillus sp. This case was not related to a resistant strain hospital outbreak (AU)


Assuntos
Humanos , Masculino , Prótese do Joelho/tendências , Prótese do Joelho , Infecções/complicações , Infecções/diagnóstico , Infecções/tratamento farmacológico , Controle de Infecções/métodos , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus epidermidis/patogenicidade , Bacteriemia/complicações , Bacteriemia/tratamento farmacológico , Prótese do Joelho/microbiologia , Staphylococcus epidermidis , Bacteriemia/terapia , Bacillus/patogenicidade
13.
Int. microbiol ; 14(4): 213-223, dic. 2011.
Artigo em Inglês | IBECS | ID: ibc-102986

RESUMO

The presence of the antimicrobial peptide (AMP) biosynthetic genes srfAA (surfactin), bacA (bacylisin), fenD (fengycin), bmyB (bacyllomicin), spaS (subtilin), and ituC (iturin) was examined in 184 isolates of Bacillus spp. obtained from plant environments (aerial, rhizosphere, soil) in the Mediterranean land area of Spain. Most strains had between two and four AMP genes whereas strains with five genes were seldom detected and none of the strains had six genes. The most frequent AMP gene markers were srfAA, bacA, bmyB, and fenD, and the most frequent genotypes srfAA-bacA-bmyB and srfAAbacA- bmyB-fenD. The dominance of these particular genes in Bacillus strains associated with plants reinforces the competitive role of surfactin, bacyllomicin, fengycin, and bacilysin in the fitness of strains in natural environments. The use of these AMP gene markers may assist in the selection of putative biological control agents of plant pathogens (AU)


No disponible


Assuntos
Humanos , Peptídeos Catiônicos Antimicrobianos/genética , Bacillus/genética , Plantas/microbiologia , Controle de Pragas/tendências , Marcadores Genéticos , Espanha
14.
Int. microbiol ; 9(2): 111-118, jun. 2006. tab, graf
Artigo em En | IBECS | ID: ibc-048322

RESUMO

A Bacillus strain producing a bacteriocin-like substance was characterized by biochemical profiling and 16S rDNA sequencing. Phylogenetic analysis indicated that the strain has high sequence similarity with Bacillus amyloliquefaciens. The antimicrobial substance was inhibitory to pathogenic and food-spoilage bacteria, such as Listeria monocytogenes, Bacillus cereus, Serratia marcescens, and Pasteurella haemolytica. It was stable over a wide temperature range, but lost activity when the temperature reached 121 degrees C/15 min. Maximum activity was observed at acidic and neutral pH values, but not at alkaline pH. The antimicrobial substance was sensitive to the proteolytic action of trypsin, papain, proteinase K, and pronase E. Except for iturins, other antimicrobial peptides have not been described for B. amyloliquefaciens. The identification of a bacteriocin-like inhibitory substance active against L. monocytogenes addresses an important aspect of food protection (AU)


Se ha caracterizado una cepa de Bacillus productora de una substancia del tipo bacteriocina mediante perfiles bioquímicos y secuenciación del rDNA 16S. El análisis filogenético indicó que la cepa presentaba una gran similitud de secuencia con Bacillus amylolique faciens. La sustancia antimicrobiana era inhibitoria para algunas bacterias patógenas y causantes del deterioro de los alimentos como Listeria monocytogenes, Bacillus cereus, Serrati amarcescens y Pasteurella haemolytica. La sustancia era estable en una amplia gama de temperaturas, pero perdía la actividad cuando la temperatura alcanzaba 121°C/15 min. La actividad máxima fue observada a valores de pH ácidos y neutros, pero no a pH alcalinos. La sustancia antimicrobiana era sensible a la acción proteolítica de la tripsina, la papaína, la proteinasa K y la pronasa E. Excepto las iturinaos, no se han descrito otros péptidos antimicrobianos de B. amyloliquefaciens. La identificación de una sustancia tipo bacteriocina activa contra L. monocytogenes cubre un aspecto importante en la protección de los alimentos (AU)


Assuntos
Antibacterianos/provisão & distribuição , Antibacterianos/química , Bacillus/metabolismo , Bacteriocinas/química , Bacteriocinas/provisão & distribuição , Filogenia , RNA Ribossômico 16S/genética , Brasil , Temperatura Alta , Concentração de Íons de Hidrogênio , Antibacterianos/biossíntese , Bacillus/classificação , Bacillus/genética , Bacteriocinas/biossíntese , Listeria monocytogenes/crescimento & desenvolvimento
15.
Int. microbiol ; 9(2): 119-124, jun. 2006. tab, graf
Artigo em En | IBECS | ID: ibc-048326

RESUMO

Hydrocarbon-degrading microorganisms from natural environments have been isolated and identified using culture-dependent or molecular techniques. However, there has been little research into the occurrence of microorganisms incorporated into crude oil in the initial steps of extraction and handling, which can reduce the quality of stored petroleum. In the present study, a packed-column reactor filled with autoclaved perlite soaked with crude oil was subjected to a continuous flow of sterile medium in order to determine the presence of potential hydrocarbon degraders. Microorganisms developed on the surface of the perlite within a period of 73 days. DNA was extracted from the biofilm and then PCR-amplified using 16S rRNA bacterial and archaeal primers and 18S rRNA eukaryotic primers. No amplification was obtained using archaeal primers. However, denaturing gradient gel electrophoresis (DGGE) revealed the presence of unique bands indicating bacterial and eukaryotic amplification. Excision of these bands, sequencing, and subsequent BLAST search showed that they corresponded to Bacillus sp. and Aspergillus versicolor. The fungus was later isolated from intact perlite in agar plates. A bacterial clone library was used to confirm the presence in the biofilm of a unique hydrocarbon-degrading bacterium closely related to Bacillus sp. Analysis of the petroleum components by gas chromatography showed that there n-alkanes, aromatic hydrocarbons, and carbazoles were degraded (AU)


Algunos autores han aislado e identificado microorganismos degradadores de petróleo utilizando técnicas moleculares o dependientes de cultivo. Sin embargo, se ha investigado poco la presencia de microorganismos que entran en contacto con el petróleo en las fases iniciales de su extracción y manipulación, circunstancia que puede reducir la calidad del petróleo almacenado. Mediante un reactor con una columna cargada con perlita esterilizada en autoclave y empapada de petróleo, y sujeto a un flujo continuo de medio estéril, determinamos la presencia de posibles degradadores de hidrocarburos. En la superficie de la perlita se desarrollaron microorganismos en un período de 73 días. Se extrajo el DNA del biofilm, y se amplificó por PCR con cebadores para el 16S rRNA de bacterias y arqueas y con cebadores para el 18S rRNA de eucariotas. No se obtuvo ampliación del DNA de arqueas, pero el análisis por electroforesis en gel con gradiente desnaturalizante (DGGE) reveló la presencia de bandas únicas en la amplificación de bacterias y eucariotas. La escisión de estas bandas, la secuenciación y la subsiguiente búsqueda en BLAST demostraron que correspondían a Bacillus sp. y a Aspergillus versicolor. El hongo fue aislado posteriormente en placas de agar a partir de perlita intacta. También se llevó a cabo una biblioteca genética bacteriana, que confirmó la presencia de una única bacteria degradadora de petróleo en el biofilm, muy próxima a Bacillus sp. El análisis de los componentes del petróleo por cromatografía de gases mostró que había habido degradación de n-alcanos, hidrocarburos aromáticos y carbazoles (AU)


Assuntos
Aspergillus/metabolismo , Bacillus/metabolismo , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Ecossistema , Biofilmes , Aspergillus/genética , Bacillus/genética , Eletroforese em Gel de Poliacrilamida/métodos , Hidrocarbonetos/química , Reação em Cadeia da Polimerase/métodos , Reatores Biológicos/microbiologia
16.
Int. microbiol ; 8(4): 251-258, dic. 2005. ilus, tab
Artigo em En | IBECS | ID: ibc-043474

RESUMO

The non-phosphorylating glyceraldehyde 3-phosphate dehydrogenase (GAPDHN, NADP+ -specific, EC 1.2.1.9) is present in green eukaryotes and some Streptococcus strains. The present report describes the results of activity and immunoblot analyses, which were used to generate the first survey of bacterial GAPDHN distribution in a number of Bacillus, Streptococcus and Clostridium strains. Putative gapN genes were identified after PCR amplification of partial 700-bp sequences using degenerate primers constructed from highly conserved protein regions. Alignment of the amino acid sequences of these fragments with those of known sequences from other eukaryotic and prokaryotic GAPDHNs, demonstrated the presence of conserved residues involved in catalytic activity that are not conserved in aldehyde dehydrogenases, a protein family closely linked to GAPDHNs. The results confirm that the basic structural features of the members of the GAPDHN family have been conserved throughout evolution and that no identity exists with phosphorylating GAPDHs. Furthermore, phylogenetic trees generated from multiple sequence alignments suggested a close relationship between plant and bacterial GAPDHN families (AU)


La gliceraldehído-3-fosfato deshidrogenasa no-fosforilante (GAPDHN, NADP+ -específica, EC 1.2.1.9) está presente en organismos eucariotas fotosintéticos y en algunas cepas de Streptococcus y Clostridium. En este trabajo se presentan los resultados de los análisis de actividad e inmunotransferencia, que se utilizaron para la primera prospección de la distribución de GAPDHN bacteriana en diversas cepas de Bacillus, Streptococcus y Clostridium. Se han identificado genes putativos gapN mediante amplificación por PCR de secuencias parciales de 700 bp utilizando cebadores degenerados construidos a partir de regiones proteínicas muy conservadas. Las secuencias de aminoácidos de estos fragmentos se alinearon con las de otras secuencias conocidas de GAPDHN eucarióticas y procarióticas, lo que demuestra la presencia de residuos conservados que participan en la actividad catalítica y que no se han conservado en las aldehído deshidrogenasas, una familia de proteínas estrechamente relacionadas con las GAPDHN. Los resultados confirman que las características estructurales básicas de los miembros de la familia GAPDHN se han conservado durante la evolución y que no existe identidad con las GAPDH fosforilantes. Además, los árboles filogenéticos generados a partir de alineaciones de secuencia múltiples sugieren una estrecha relación entre las familias GAPDHN en plantas y bacterias (AU)


Assuntos
Bactérias Gram-Positivas/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/análise , Streptococcus/imunologia , Bacillus/imunologia , Clostridium/imunologia , Análise de Sequência de Proteína
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