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1.
Pediatr Infect Dis J ; 40(12): e519-e520, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34292269

RESUMO

We describe a newborn infant with hydrocephalus and a ventriculoperitoneal shunt infection caused by Brevibacterium casei. Essential for correct diagnosis was rapid species identification by matrix-assisted laser desorption/ionization time-of-flight, after initial report of coryneform bacteria. The patient responded well to vancomycin and rifampicin for 15 days. The shunt was not removed. Repeated cerebrospinal fluid cultures up to 4 months after therapy remained negative.


Assuntos
Antibacterianos/uso terapêutico , Brevibacterium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Brevibacterium/patogenicidade , Infecções por Bactérias Gram-Positivas/líquido cefalorraquidiano , Humanos , Hidrocefalia/microbiologia , Recém-Nascido , Masculino , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Resultado do Tratamento , Derivação Ventriculoperitoneal/efeitos adversos
2.
Biocontrol Sci ; 25(3): 139-147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32938843

RESUMO

Halotolerant Brevibacterium sp. JCM 6894 grew at 37ºC in the presence of 2.3 M KCl, while the growth was repressed with the same concentration of NaCl. When resting cells, 107.4 ± 0.1 (CFU·mL-1), prepared from cells grown in the absence of salts at 30ºC, were exposed to 3.3 M NaCl for 36 h at 42ºC, reduction of the number of resting cells was maintained within a 1-log cycle in the presence of proline, betaine, or ectoine (50 mM). In the presence of 3.3 M KCl, the most functional osmoprotectant was sodium glutamate (50 mM), and the value was 107.2 ± 0.1 (CFU·mL-1) when exposed for 72 h at 42ºC. In the absence of osmoprotectants, the value was reduced to four orders of magnitude in each experimental condition. The number of resting cells, 106.8 ± 0.1 (CFU·mL-1), prepared from grown cells pre-adapted to 2.3 M KCl at 37ºC, was hardly reduced when exposed to 3.3 M KCl in the presence of sodium glutamate more than 50 mM for 72 h at 42ºC. Those results indicate that the isolate can sense the difference in hyper KCl stress as opposed to hyper NaCl stress, and different kinds of osmoadaptation systems can function to cope with each hyper salt stress.


Assuntos
Brevibacterium/efeitos dos fármacos , Temperatura Alta , Pressão Osmótica , Cloreto de Potássio/farmacologia , Glutamato de Sódio/farmacologia , Brevibacterium/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Temperatura
3.
Braz J Microbiol ; 51(4): 1885-1895, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32729030

RESUMO

Cellular response against different heavy metal stress differs with the metal. Arsenic and chromium are heavy metals and toxic to living systems. The concentration of these metals in seawater is very low. However, due to their solubility in nature, they actively enter cells via various transport mechanisms and cause damage to the cells. Brevibacterium casei #NIOSBA88, a marine-derived, gram-positive isolate was multi-metal tolerant. Proteomic analysis of this isolate in response to arsenic and chromium resulted in the identification of total 2549 proteins, out of which 880 proteins were found to be commonly expressed at 750 mgL-1 arsenic and 100 mgL-1 chromium and in absence of both the metals. In contrast, 533, 212, and 270 proteins were found to be unique in the absence of any metal, 750 mgL-1 of arsenic and 100 mgL-1 of chromium respectively. Proteins such as antibiotic biosynthesis monooxygenase, ArsR family transcriptional regulator, cytochrome C oxidase subunit II, and thioredoxin reductase were exclusively expressed only in response to arsenic and chromium. Other proteins like superoxide dismutase, lipid hydroperoxide reductase, and thioredoxin-disulfide reductase were found to be upregulated in response to both the metals. Most of the proteins involved in the normal cell functioning were found to be downregulated. Major metabolic functions affected include amino acid metabolism, carbohydrate metabolism, translation, and energy metabolism. Peptide mass fingerprinting of Brevibacterium casei #NIOSBA88 exposed to arsenic and chromium respectively revealed the deleterious effect of these metals on the bacterium and its strategy to overcome the stress.


Assuntos
Arsênio/metabolismo , Brevibacterium/metabolismo , Cromo/metabolismo , Proteômica , Proteínas de Bactérias/isolamento & purificação , Brevibacterium/efeitos dos fármacos
4.
Braz J Microbiol ; 51(2): 685-689, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32067212

RESUMO

Despite its low virulence potential and a commensal lifestyle as a member of the human skin microbiota, Brevibacterium casei has been increasingly reported as an opportunistic pathogen, especially in immunocompromised patients. Here, we present the draft genome sequence of the S51 strain isolated from a bloodstream infection. To the best of the authors' knowledge, this is the first report of the draft genome sequence of the B. casei strain isolated from the clinical infection. The strain was identified using phenotypic and molecular methods and subsequently sequenced using the next-generation sequencing. The draft whole genome was assembled de novo, automatically annotated by Rapid Annotations using Subsystems Technology (RAST) server and scrutinized to predict the presence of virulence, resistance, and stress response proteins. The genome size of the S51 strain was 3,743,532 bp and an average G+C content was 68.3%. The predicted genes included 48 genes involved in resistance to antibiotics (including vancomycin, fluoroquinolones, and beta-lactams) and toxic compounds (heavy metals), 16 genes involved in invasion and intracellular resistance (Mycobacterium virulence operons), and 94 genes involved in stress response (osmotic, oxidative stress, cold and heat shock). ResFinder has indicated the presence of a beta-lactamase, and a phenotypic analysis showed resistance to penicillin. This whole-genome NGS project for the S51strain has been deposited at EMBL/GenBank under the accession no. QNGF00000000.


Assuntos
Bacteriemia/microbiologia , Brevibacterium/genética , Genoma Bacteriano , Infecções por Bactérias Gram-Positivas/microbiologia , Antibacterianos/farmacologia , Composição de Bases , Brevibacterium/efeitos dos fármacos , Brevibacterium/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Humanos , Análise de Sequência de DNA , Virulência , Sequenciamento Completo do Genoma
5.
Infez Med ; 26(3): 263-265, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30246770

RESUMO

Brevibacteria are part of the normal flora of the skin and adjacent structures, but have been increasingly encountered in humans as opportunistic pathogens and have been isolated from various clinical specimens, generally causing infections in immuno-compromised patients. We present a case of a port-a-cath-related bacteraemia caused by Brevibacterium casei in a woman with a prior history of bilateral breast cancer. The clinical outcome was favourable.


Assuntos
Bacteriemia/microbiologia , Brevibacterium/isolamento & purificação , Infecções Relacionadas a Cateter/microbiologia , Infecção Hospitalar/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções Oportunistas/microbiologia , Dispositivos de Acesso Vascular/microbiologia , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/etiologia , Neoplasias da Mama/terapia , Brevibacterium/efeitos dos fármacos , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/etiologia , Terapia Combinada , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/etiologia , Remoção de Dispositivo , Contaminação de Equipamentos , Feminino , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/etiologia , Humanos , Linezolida/uso terapêutico , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/terapia , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/etiologia , Teicoplanina/uso terapêutico , Dispositivos de Acesso Vascular/efeitos adversos
6.
Microbiol Res ; 215: 89-101, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30172313

RESUMO

Soil salinity is one of the major limitations that affects both plant and its soil environment, leading to reduced agricultural production. Evaluation of stress severity by plant physical and biochemical characteristics is an established way to study plant-salt stress interaction, but the halotolerant properties of plant growth promoting bacteria (PGPB) along with plant growth promotion is less studied till date. The aim of the present study was to elucidate the strategy, used by ACC deaminase-containing halotolerant Brevibacterium linens RS16 to confer salt stress tolerance in moderately salt-tolerant (FL478) and salt-sensitive (IR29) rice (Oryza sativa L.) cultivars. The plants were exposed to salt stress using 0, 50, and 100 mM of NaCl with and without bacteria. Plant physiological and biochemical characteristics were estimated after 1, 5, 10 days of stress application. H+ ATPase activity and the presence of hydroxyectoine gene (ectD) that is responsible for compatible solute accumulation were also analyzed in bacteria. The height and dry mass of bacteria inoculated plants significantly increased compared to salt-stressed plants, and the differences increased in time dependent manner. Bacteria priming reduced the plant antioxidant enzyme activity, lipid peroxidation and it also regulated the salt accumulation by modulating vacuolar H+ ATPase activity. ATPase activity and presence of hydroxyectoine gene in RS16 might have played a vital role in providing salt tolerance in bacteria inoculated rice cultivars. We conclude that dual benefits provided by the halotolerant plant growth promoting bacteria (PGPB) can provide a major way to improve rice yields in saline soil.


Assuntos
Antioxidantes/metabolismo , Brevibacterium/fisiologia , Oryza/microbiologia , Oryza/fisiologia , Desenvolvimento Vegetal/fisiologia , ATPases Translocadoras de Prótons/metabolismo , Plantas Tolerantes a Sal/microbiologia , Plantas Tolerantes a Sal/fisiologia , Diamino Aminoácidos/genética , Biomassa , Brevibacterium/efeitos dos fármacos , Brevibacterium/enzimologia , Carbono-Carbono Liases , Catalase/metabolismo , Genes Bacterianos/genética , Genótipo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Oryza/efeitos dos fármacos , Oryza/enzimologia , Estresse Oxidativo/fisiologia , Desenvolvimento Vegetal/efeitos dos fármacos , Folhas de Planta/enzimologia , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Espécies Reativas de Oxigênio , Salinidade , Cloreto de Sódio/farmacologia , Solo , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/fisiologia
7.
Planta Med ; 84(9-10): 662-673, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29579744

RESUMO

Foot odour (bromodosis) is an embarrassing and perplexing condition mostly caused by bacteria of the Brevibacterium species. Essential oils are a credible option as an affordable treatment of odour and contribute towards antimicrobial efficacy. Therefore, this study sets out to investigate the antimicrobial activity of essential oil combinations against odour-causing bacteria. The broth microdilution method was used to investigate the antimicrobial activity of 119 essential oil combinations, and the fractional inhibitory index was calculated to determine the interactive profile. Combinations that resulted in synergy in 1 : 1 ratios were further evaluated in different concentrations, and isobolograms were plotted to determine the influence of the ratio on overall activity. Numerous combinations could be identified as having synergistic interactions against the Brevibacterium spp. and no antagonism was observed. The combination of Juniperus virginiana (juniper) and Styrax benzoin (benzoin) demonstrated synergy against all three Brevibacterium spp. tested and J. virginiana was the essential oil responsible for the majority of the synergistic interactions. The results reported here confirm the promising potential of the majority of these oils and selected combinations in treating and controlling bromodosis.


Assuntos
Anti-Infecciosos/farmacologia , Brevibacterium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Aromaterapia , Pé/fisiopatologia , Humanos
8.
ScientificWorldJournal ; 2014: 108562, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25478582

RESUMO

A novel selenium- (Se-) hyperaccumulating plant, Cardamine hupingshanesis, accumulating Se as a form of SeCys2, was discovered in Enshi, Hubei, China, which could not be explained by present selenocysteine methyltransferase (SMT) theory. However, it is interesting to investigate if rhizosphere bacteria play some roles during SeCys2 accumulation. Here, one Se-tolerant rhizosphere strain, Microbacterium oxydans, was isolated from C. hupingshanesis. Phylogenetic analysis and 16S rRNA gene sequences determined the strain as a kind of Gram positive bacillus and belonged to the family Brevibacterium frigoritolerans. Furthermore, Se tolerance test indicated the strain could grow in extreme high Se level of 15.0 mg Se L(-1). When exposed to 1.5 mg Se L(-1), SeCys2 was the predominant Se species in the bacteria, consistent with the Se species in C. hupingshanesis. This coincidence might reveal that this strain played some positive effect in SeCys2 accumulation of C. hupingshanesis. Moreover, when exposed to 1.5 mg Se L(-1) or 15.0 mg Se L(-1), As absorption diminished in the logarithmic phase. In contrast, As absorption increased when exposed to 7.5 mg Se L(-1), indicating As metabolism processes could be affected by Se on this strain. The present study provided a sight on the role of rhizosphere bacteria during Se accumulation for Se-hyperaccumulating plant.


Assuntos
Brevibacterium/metabolismo , Cardamine/genética , Filogenia , Selênio/metabolismo , Brevibacterium/efeitos dos fármacos , Cardamine/efeitos dos fármacos , Cardamine/metabolismo , Metiltransferases/metabolismo , RNA Ribossômico 16S/genética , Rizosfera , Selênio/toxicidade
9.
Biomed Res Int ; 2014: 313684, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25313359

RESUMO

In an attempt to determine the antioxidant/prooxidant, antibacterial/probacterial action of flavan-3-ols and procyanidins from grape seeds, pure catechin (CS), and an aqueous grape seed extract (PE), were applied in the absence and presence of pure lipoxygenase (LS) or in extract (LE) to leucocyte culture, Escherichia coli B 41 and Brevibacterium linens, and observed whether there was any effect on lipid peroxidation, cytotoxicity, or growth rate. Short time periods of coincubation of cells with the polyphenols, followed by the exposure to LS and LE, revealed a high level of lipid peroxidation and a prooxidative effect. Longer coincubation and addition of LS and LE resulted in the reversal of the prooxidant action either to antioxidant activity for CS + LS and PE + LS or to the control level for CS + LE and PE + LE. Lipid peroxidation was significantly reduced when cells were exposed to polyphenols over a longer period. Longer exposure of E. coli to CS or PE followed by addition of LS for 3 h resulted in bactericidal activity. Significant stimulatory effect on microbial growth was observed for PE + LS and PE + LE treatments in B. linens, illustrating the potential probacterial activity in B. linens cultures. Lipoxygenase-polyphenols complex formation was found to be responsible for the observed effects.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Extrato de Sementes de Uva/farmacologia , Lipoxigenase/farmacologia , Oxidantes/farmacologia , Animais , Brevibacterium/efeitos dos fármacos , Brevibacterium/crescimento & desenvolvimento , Catequina/farmacologia , Respiração Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Cavalos , Leucócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Polifenóis/farmacologia , Glycine max/enzimologia , Espectrofotometria Ultravioleta , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Biomed Khim ; 60(4): 448-61, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25249528

RESUMO

The preparative microbial synthesis of amino acids labelled with stable isotopes, including deuterium ( 2 H), suitable for biomedical applications by methylotrophic bacteria was studied using L-phenylalanine as example. This amino acid is secreted by Gram-negative aerobic facultative methylotrophic bacteria Brevibacterium methylicum, assimilating methanol via ribulose-5-monophosphate (RMP) cycle of assimilation of carbon, The data on adaptation of L-phenylalanine secreted by methylotrophic bacterium В. methylicum to the maximal concentration of deuterium in the growth medium with 98% 2 Н 2 O and 2% [ 2 Н]methanol, and biosynthesis of deuterium labelled L-phenylalanine With different levels of enrichment are presented. The strain was adapted by means of plating initial cells on firm (2% agarose) minimal growth media with an increasing gradient of 2 Н 2 O concentration from 0; 24.5; 49.0; 73.5 up to 98% 2 Н 2 O followed by subsequent selection of separate colonies stable to the action of 2 Н 2 O. These colonies were capable to produce L-phenylalanine. L-phenylalanine was extracted from growth medium by extraction with isopropanol with the subsequent crystallization in ethanol (output 0.65 g/l). The developed method of microbial synthesis allows to obtain deuterium labelled L-phenylalanine with different levels of isotopic enrichment, depending on concentration of 2 Н 2 O in growth media, from 17% (on growth medium with 24,5% 2 Н 2 O) up to 75% (on growth medium with 98% 2 Н 2 O) of deuterium in the molecule that is confirmed with the data of the electron impact (EI) mass- spectrometry analysis of methyl ethers of N-dimethylamino(naphthalene)-5-sulfochloride (dansyl) phenylalanine in these experimental conditions.


Assuntos
Brevibacterium/metabolismo , Carbono/metabolismo , Deutério/metabolismo , Fenilalanina/biossíntese , Ribulosefosfatos/metabolismo , 2-Propanol , Adaptação Fisiológica , Brevibacterium/efeitos dos fármacos , Brevibacterium/crescimento & desenvolvimento , Compostos de Dansil/química , Deutério/farmacologia , Marcação por Isótopo/métodos , Extração Líquido-Líquido , Espectrometria de Massas , Metanol/metabolismo , Fenilalanina/isolamento & purificação , Solventes
11.
Carbohydr Polym ; 106: 319-25, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24721085

RESUMO

This study aims to investigate the green synthesis of silver nanoparticles (AgNPs) by Erigeron annuus (L.) pers flower extract as reducing and capping agent, and evaluation of their antibacterial activities for the first time. The obtained product was confirmed by UV-Vis spectrum, high resolution-transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies. The optimum AgNPs production was achieved at pH 7, metal silver (Ag(+) ion) concentration of 2.0mM, flower extract concentration 4%, and time 335 min. In addition, the antibacterial activity of cotton fabrics and tanned leather loaded with AgNPs, commercial AgNPs, flower extract, Ag(+) ion and blend of flower extract with AgNPs were evaluated against Gram-positive odor causing bacteria Brevibacterium linens and Staphylococcus epidermidis. The results showed maximum zone of inhibition (ZOI) by the cotton fabrics embedded with blend of flower extract and AgNPs against B. linens. The structure and morphology of cotton fabric and leather samples embedded with AgNPs, Ag(+) ion and blend of flower extract with AgNPs were examined under field emission scanning electron microscope.


Assuntos
Antibacterianos/síntese química , Brevibacterium/efeitos dos fármacos , Erigeron/química , Química Verde , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Substâncias Redutoras/farmacologia , Prata/química , Staphylococcus epidermidis/efeitos dos fármacos , Têxteis , Antibacterianos/química , Antibacterianos/farmacologia , Fibra de Algodão , Flores/química , Microscopia Eletrônica de Varredura , Odorantes/prevenção & controle , Oxirredução , Prata/farmacologia , Espectrofotometria/métodos , Curtume
12.
Ecotoxicology ; 21(5): 1281-90, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22430059

RESUMO

Bensulfuron-methyl (BSM) is a new kind of sulfonylurea herbicide widely used to control broad-leaf weeds in rice paddies. The aim of this work was to study BSM biodegradation in paddy soils with BSM-degrading bacteria Bacillus megaterium L1 and Brevibacterium sp. BH and its effect on the structures of soil bacterial community. More than 90 % of BSM could be degraded in paddy soils with 0.0355 mg kg⁻¹ BSM concentration. Addition of BSM-degrading bacterial strains Bacillus megaterium L1 into BSM contaminated paddy soil could have the half-life time of BSM compared to treatment without Bacillus megaterium L1 inoculation. Denaturing gradient gel electrophoresis and principle component analysis indicated that the diversity of the soil microbial community structure changed along with the addition of BSM, which recovered at the end of the experiment (5 weeks). Addition of BSM-degrading bacteria Bacillus megaterium L1 enriched the diversity of soil microbial community structure in paddy soils. This study provides information on the biodegradation of BSM and BSM's influences on the soil bacteria microbial community structures.


Assuntos
Bacillus megaterium/efeitos dos fármacos , Brevibacterium/efeitos dos fármacos , Herbicidas/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade , Compostos de Sulfonilureia/toxicidade , Bacillus megaterium/crescimento & desenvolvimento , Biodegradação Ambiental , Brevibacterium/crescimento & desenvolvimento , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Meia-Vida , Oryza , Filogenia
13.
Mikrobiol Z ; 71(4): 3-8, 2009.
Artigo em Ucraniano | MEDLINE | ID: mdl-19938609

RESUMO

Enterobacter hormaechei and Brevibacterium antarcticum strains isolated from ornithogenic soils of Galindez Island (West Antarctica) were investigated for their resistance to Cu2+ cations and for their capacity to Cu2+ uptake from the environment. The studied strains are capable to grow in the concentration range of copper 100-1100 mg/l and to extract 11-75% of Cu2+ from the environment depending on cultivation parameters and copper output concentration in the culture medium.


Assuntos
Brevibacterium/crescimento & desenvolvimento , Cobre/farmacologia , Farmacorresistência Bacteriana , Enterobacter/crescimento & desenvolvimento , Adaptação Biológica , Regiões Antárticas , Técnicas Bacteriológicas , Biomassa , Brevibacterium/efeitos dos fármacos , Cátions Bivalentes/farmacologia , Clima Frio , Sulfato de Cobre/farmacologia , Meios de Cultura/química , Enterobacter/efeitos dos fármacos , Microbiologia do Solo , Temperatura
14.
Biosens Bioelectron ; 24(8): 2637-42, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19230647

RESUMO

The lyophilized biomass of bacterium Brevibacterium ammoniagenes was immobilized in polystyrene sulphonate-polyaniline (PSS-PANI) conducting polymer on a Pt twin wire electrode by potentiostatic electropolymerization. The bacterial cells retained their viability as well as urease activity under entrapped state, as confirmed with bacterial live-dead fluorescent assay and enzymatic assays. The entrapped cells were visualized using scanning electron microscope. The immobilized cells were used as a source of unpurified urease to develop a conductometric urea biosensor. The catalytic action of urease in the sensor released ammonia, thereby causing an increase in the pH of the microenvironment. The pH dependant change in the resistivity of the polymer was used as the basis of sensing mechanism. The sensor response was linear over a range of 0-75 mM urea with a sensitivity of 0.125 mM(-1). The sensor could be reused for 12-15 independent measurements and was quite stable in dry as well as buffered storage condition at 4 degrees C for at least 7 days.


Assuntos
Bioensaio/instrumentação , Técnicas Biossensoriais/instrumentação , Brevibacterium/enzimologia , Eletroquímica/instrumentação , Ureia/análise , Urease/química , Compostos de Anilina/química , Bioensaio/métodos , Brevibacterium/efeitos dos fármacos , Eletrodos , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ureia/farmacologia
15.
Biotechnol Bioeng ; 99(4): 941-8, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17696218

RESUMO

Brevibacterium sp. JCM 6894 cells grown in the presence of 1.5-2.5 M NaCl for 24 h at 30 degrees C were subjected to the osmotic downshock. Downshocked cells after ectoine release were grown for further 24 h in the fresh medium with same salinity as before shock. When this cyclic system was applied to the strain JCM 6894, the amount of ectoine in the cells increased with an increase of incubation time, which indicates that the cells manipulated by the present conditions were enough active to survive and synthesize ectoine after several times of osmotic downshock. In the presence of 2 M NaCl, the highest yield of ectoine released was achieved in this cyclic system, more than 2.4 g/L during 7 days of incubation. (1)H and (13)C-NMR analyses of solutes released from the cells by the osmotic downshock showed the presence of only ectoine with high purity. Release of ectoine from the cells was carried out within 5 min and its rates were increased by the dilution in the downshock treatment. For the convenience of operations, non-sterilized medium containing 2 M NaCl was examined for the cell growth in the present system, in which almost same level of ectoine yield, release rates, and cell viability were observed as those of sterilized medium.


Assuntos
Diamino Aminoácidos/metabolismo , Brevibacterium/fisiologia , Técnicas de Cultura de Células/métodos , Cloreto de Sódio/farmacologia , Brevibacterium/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Pressão Osmótica/efeitos dos fármacos
16.
Appl Microbiol Biotechnol ; 74(6): 1320-32, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17225104

RESUMO

The expression of genes possibly involved in L-methionine and lactate catabolic pathways were performed in Brevibacterium linens (ATCC9175) in the presence or absence of added L-methionine. The expression of 27 genes of 39 selected genes differed significantly in L-methionine-enriched cultures. The expression of the gene encoding L-methionine gamma-lyase (MGL) is high in L-methionine-enriched cultures and is accompanied by a dramatic increase in volatile sulfur compounds (VSC) biosynthesis. Several genes encoding alpha-ketoacid dehydrogenase and one gene encoding an acetolactate synthase were also up-regulated by L-methionine, and are probably involved in the catabolism of alpha-ketobutyrate, the primary degradation product of L-methionine to methanethiol. Gene expression profiles together with biochemical data were used to propose catabolic pathways for L-methionine in B. linens and their possible regulation by L-methionine.


Assuntos
Brevibacterium/efeitos dos fármacos , Metionina/farmacologia , Transcrição Gênica/efeitos dos fármacos , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/genética , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/metabolismo , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Brevibacterium/genética , Brevibacterium/metabolismo , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Metionina/metabolismo , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , Compostos de Enxofre/metabolismo
17.
J Biosci Bioeng ; 101(2): 178-84, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16569616

RESUMO

Downshock treatment of the halotolerant Brevibacterium sp. JCM 6894 was a prerequisite for proline uptake which is a function for cell survival. Hydroxyectoine served as an effective stimulator for the proline uptake and cell survival of the downshocked cells of this strain. Duration of osmotic downshock, downshock strength, and the kinds of osmolyte affected the efficient rate of growth (ERG) and the uptake of proline. A shorter duration of osmotic downshock, that is

Assuntos
Diamino Aminoácidos/farmacologia , Brevibacterium/efeitos dos fármacos , Brevibacterium/fisiologia , Pressão Osmótica , Prolina/farmacocinética , Carboidratos/farmacologia , Carbono/metabolismo , Proliferação de Células/efeitos dos fármacos , Meios de Cultura , Prolina/farmacologia
18.
J Biosci Bioeng ; 101(1): 57-62, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16503292

RESUMO

Halotolerant Brevibacterium sp. JCM 6894 that was subjected to an osmotic downshock (0.7 M NaCl to 0 M) was examined for its survival and uptake of ectoine in the presence of ectoine and/or carbon sources. In the presence of ectoine alone, the rates of ectoine uptake by the 1 h-downshocked cells were low and high in the absence and presence of 0.7 M NaCl, respectively, which were in parallel with the rates of cell growth. The presence of glutamate or amino acids together with ectoine exerted a stimulative effect on the survival of downshocked cells. The incubation time of the cells subjected to osmotic downshock strongly affected ectoine uptake as well as the cell growth of this strain, suggesting that the transporter of ectoine in the strain JCM 6894 was stimulated during the osmotic downshock for about 1 h. Different downshock strengths had marked effects on the rate of ectoine uptake when the downshocked cells were incubated in the presence of NaCl.


Assuntos
Diamino Aminoácidos/metabolismo , Brevibacterium/efeitos dos fármacos , Brevibacterium/metabolismo , Ácido Glutâmico/farmacologia , Transporte Biológico , Brevibacterium/crescimento & desenvolvimento , Pressão Osmótica/efeitos dos fármacos , Solução Salina Hipertônica/farmacologia
19.
FEMS Microbiol Ecol ; 52(1): 129-37, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16329899

RESUMO

Stationary phase cells of the halophilic archaea Halobacterium salinarium and Halorubrum distributum, growing at 3-4 M NaCl, and of the halotolerant bacterium Brevibacterium antiquum, growing with and without 2.6 NaCl, took up approximately 90% of the phosphate from the culture media containing 2.3 and 11.5 mM phosphate. The uptake was blocked by the uncoupler FCCP. In B. antiquum, EDTA inhibited the phosphate uptake. The content of polyphosphates in the cells was significantly lower than the content of orthophosphate. At a high phosphate concentration, up to 80% of the phosphate taken up from the culture medium was accumulated as Mg(2)PO(4)OH x 4H(2)O in H. salinarium and H. distributum and as NH(4)MgPO(4) x 6H(2)O in B. antiquum. Consolidation of the cytoplasm and enlargement of the nucleoid zone were observed in the cells during phosphate accumulation. At phosphate surplus, part of the H. salinarium and H. distributum cell population was lysed. The cells of B. antiquum were not lysed and phosphate crystals were observed in the cytoplasm.


Assuntos
Archaea/metabolismo , Brevibacterium/metabolismo , Compostos de Magnésio/metabolismo , Fosfatos/farmacocinética , Archaea/efeitos dos fármacos , Archaea/crescimento & desenvolvimento , Archaea/ultraestrutura , Brevibacterium/efeitos dos fármacos , Brevibacterium/crescimento & desenvolvimento , Brevibacterium/ultraestrutura , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/toxicidade , Citoplasma/metabolismo , Microscopia Eletrônica , Fosfatos/isolamento & purificação , Fosfatos/metabolismo , Cloreto de Sódio/metabolismo , Espectrofotometria Atômica , Fatores de Tempo , Desacopladores/toxicidade
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