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1.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(10): 549-551, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34620485

RESUMO

CLINICAL CASE: 49-year-old man with diabetic macular edema refractory to antiangiogenics, it is decided to perform therapy with intravitreal dexamethasone implant (Ozurdex; Allergan, California, United States of America). Seven days after treatment, he showed acute endophthalmitis suggestive signs. Despite the intravitreal injection of antibiotics, the patient got worse. Vitreous sampling was repeated for Gram and cultures, and vitrectomy was performed via pars plana. The culture suggested the development of Brevibacterium species. Through an additional test, the presence of Brevibacterium casei was confirmed. Despite the treatment adjusted by antibiogram, retinal ischemia and macular atrophy was evident. DISCUSSION: Brevibacterium casei is a Gram-positive bacterium, barely pathogenic, that mainly affects immunodepressed patients. Only two cases of endophthalmitis are described, one endogenous and the other one secondary to vegetal trauma. This is the first case of endophthalmitis, secondary to an ophthalmological procedure.


Assuntos
Brevibacterium , Retinopatia Diabética , Endoftalmite , Edema Macular , Dexametasona/uso terapêutico , Implantes de Medicamento , Endoftalmite/tratamento farmacológico , Humanos , Edema Macular/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
2.
Sci Total Environ ; 799: 149261, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34371415

RESUMO

The mechanisms of struvite production by biomineralization were investigated for five microorganisms (Bacillus pumilus, Brevibacterium antiquum, Myxococcus xanthus, Halobacterium salinarum and Idiomarina loihiensis) in municipal wastewater. The microbial exponential phase of growth occurred within the first 48 h of incubation, with growth rates varying from 0.02-0.08 1/h. These five microorganisms removed 23-27 mg/L (66-79%) of ortho-phosphate from wastewater, which was recovered as biological struvite (i.e., bio-struvite) identified by morphological, X-ray diffraction and elemental analysis. Bio-struvite crystals occurred in a low extracellular supersaturation index (0.6-0.8 units). Bio-struvite formation in B. pumilus M. xanthus, H. salinarum cultures was linked to biologically induced mineralization. Whereas B. antiquum and I. loihiensis produced bio-struvite through biologically controlled mineralization mechanism because the crystals presented homogeneity in morphology and size, and intracellular vesicle-like cell structures were observed enclosing electron-dense granules/materials. Nutrient recovery through biomineralization has potential application in wastewater streams promoting circularity within the wastewater industry.


Assuntos
Biomineralização , Águas Residuárias , Alteromonadaceae , Brevibacterium , Fosfatos , Fósforo , Estruvita
3.
Chemosphere ; 281: 130986, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289630

RESUMO

The mechanisms of struvite production through biomineralisation were investigated for five microorganisms (Bacillus pumilus, Brevibacterium antiquum, Myxococcus xanthus, Halobacterium salinarum and Idiomarina loihiensis). After 72-96 h of incubation, the microbial strains tested increased the solution pH from 7.5 to 7.7 to 8.4-8.7, and removed ortho-phosphate (63-71%) and magnesium (94-99%) by biomineralisation. The minerals formed were identified as struvite (i.e. bio-struvite). Within the initial 24 h of incubation, microbial growth rates of 0.16-0.28 1/h were measured, and bio-struvite production was observed when the solution supersaturation index with respect to struvite achieved 0.6-0.8 units. The crystals produced by B. pumilus, H. salinarum and M. xanthus were thin trapezoidal-platy shaped and presented a gap size about 200 µm for intervals between cumulative volume undersize distribution at 50% and 90%. While B. antiquum and I. loihiensis produced crystals of coffin-lid/long-bar shape and a narrow size gap around 100 µm for intervals between cumulative volume percentage of 50% and 90%, indicating homogeneous crystal size distribution. Intracellular supersaturation of struvite phase was achieved within B. antiquum and I. loihiensis cells, corresponding to observation of intracellular vesicle-like structures occupied with electron-dense granules/materials. This study suggests that B. antiquum and I. loihiensis produced bio-struvite through biologically controlled mineralisation. This mechanism is the preferred for recovering nutrients from streams such as wastewater because it allows a link between manipulation of microbial growth conditions and bio-struvite production, even in highly complex streams like wastewater.


Assuntos
Compostos de Magnésio , Fósforo , Alteromonadaceae , Brevibacterium , Fosfatos , Estruvita
4.
Int J Food Microbiol ; 358: 109312, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34215422

RESUMO

Halophilic/halotolerant bacteria are generally assumed to live in natural environments, although they may also be found in foods such as cheese and seafood. These salt-loving bacteria have been occasionally characterized in cheese, and studies on their ecological and technological functions are still scarce. We therefore selected 13 traditional cheeses to systematically characterize these microorganisms in their rinds via cultural, genomic and metagenomic methods. Using different salt-based media, we identified 35 strains with unique 16S rRNA and rpoB gene sequences, whose whole genome was sequenced. Twenty are Gram-positive species including notably Brevibacterium aurantiacum (6) and Staphylococcus equorum (3), which are also frequently added as starters. ANI and pan-genomic analyses confirm the high genetic diversity of B. aurantiacum and reveal the presence of two subspecies in S. equorum, as well as the genetic proximity of several cheese strains to bovine isolates. Additionally, we isolated 15 Gram-negative strains, potentially defining ten new species of halophilic/halotolerant cheese bacteria, in particular for the genera Halomonas and Psychrobacter. The use of all the genomes sequenced in this study as a reference to complement those existing in the databases allowed us to study the representativeness of 66 species of halophilic/halotolerant bacteria in 74 cheese rind metagenomes. While Gram-positive strains may flourish in the different types of technologies, Gram-negative species are particularly abundant in cheeses with high moisture, such as washed-rind cheeses. Finally, analyses of co-occurrences reveal assemblies, including the frequent coexistence of several species of the same genus, forming moderately complex ecosystems with functional redundancies that probably ensure stable cheese development.


Assuntos
Queijo , Microbiota , Animais , Bactérias/genética , Brevibacterium , Bovinos , Queijo/análise , Metagenoma , Metagenômica , RNA Ribossômico 16S/genética , Staphylococcus
5.
Mar Pollut Bull ; 170: 112656, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34186449

RESUMO

Nickel bioaccumulation capacity of a marine Brevibacterium sp., designated as X6, was evaluated to explore its potential application in the bioremediation of Ni2+ pollutants in marine environments. The minimum Ni2+ inhibitory concentration and maximum Ni2+ bioaccumulation of X6 were 1000 mg/L and 100.95 mg/g, respectively, higher than most reported strains. Among the co-existing metal ions in seawater, K+ caused a slight adverse impact on Ni2+ uptake, followed by Na+ and Ca2+, whereas Mg2+ drastically inhibited Ni2+ bioaccumulation. Other heavy metals such as Co2+, Zn2+ and Cd2+ moderately affected Ni2+ binding, but the adverse effect of Cu2+ was severe. The investigation of the mechanism of Ni2+ bioaccumulation revealed that 66.34% of the accumulated Ni2+ was bound to the cell surface. Carboxylic, hydroxyl, amino and thiol groups participated in Ni2+ binding, while carboxylic group contributed the most, while thiol group may be more involved in Ni2+ binding at low Ni2+ concentrations.


Assuntos
Brevibacterium , Metais Pesados , Poluentes Químicos da Água , Baías , Bioacumulação , China , Metais Pesados/análise , Níquel/análise , Poluentes Químicos da Água/análise
6.
Biocontrol Sci ; 26(2): 67-74, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34092716

RESUMO

In the present study, the antifungal activity of metabolites produced by Bacillus atrophaeus B5 and a new Brevibacterium strain against Alternaria alternata was evaluated. Assays in vitro and in vivo on tomato fruit during postharvest were made. Based on the 16S rDNA gene sequence analysis, the new strain (strain B7) was identified as Brevibacterium frigoritolerans. Metabolites produced by both bacterial strains reduced the spore germination of A. alternata in vitro and decreased the severity of the alternaria rot disease on tomato fruit during postharvest. This is the first report that demonstrates the potential of B. frigoritolerans B7 as a biocontrol agent against this fungal phytopathogen. The use of metabolites produced by B. atrophaeus B5 and B. frigoritolerans B7 represents a new approach to reduce the use of chemical pesticides and control fungal decay during the postharvest stage.


Assuntos
Brevibacterium , Lycopersicon esculentum , Alternaria , Bacillus , Frutas , Doenças das Plantas/prevenção & controle
9.
J Dairy Sci ; 104(7): 7500-7508, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33838885

RESUMO

Époisses is a protected designation of origin smear-ripened cheese from the Burgundy region in France. It has an orange color and a strong flavor, both of which are generated by surface microorganisms. The objective of the present study was to investigate the microbial dynamics at the surface of Époisses cheese during ripening and postmanufacturing storage at low temperatures. Rind samples were analyzed by enumeration on agar plates and by 16S rRNA gene and internal transcribed spacer amplicon sequencing. During most of the ripening process, the counts of yeasts, which corresponded to the species Debaryomyces hansenii and Geotrichum candidum, were higher than those of the aerobic acid-sensitive bacteria. Debaryomyces hansenii reached a level of about 3 × 108 cfu/cm2, and its viability strongly decreased in the late stage of ripening and during storage at 4°C. Two of the inoculated bacterial species, Brevibacterium aurantiacum and Staphylococcus xylosus, did not establish themselves at the cheese surface. At the end of ripening, among the 18 most abundant bacterial species detected by amplicon sequencing, 14 were gram-negative, mainly from genera Psychrobacter, Vibrio, Halomonas, and Mesonia. It was hypothesized that the high moisture level of the Époisses rinds, due the humid atmosphere of the ripening rooms and to the frequent washings of the curds, favored growth of these gram-negative species. These species may be of interest for the development of efficient ripening cultures. In addition, because the orange color of Époisses cheeses could not be attributed to the growth of Brevibacterium, it would be interesting to investigate the type and origin of the pigments that confer color to this cheese.


Assuntos
Queijo , Animais , Brevibacterium , França , Geotrichum , RNA Ribossômico 16S/genética , Staphylococcus
10.
Arch Microbiol ; 203(5): 2491-2500, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33677635

RESUMO

Genome analysis gives important insights into the biosynthetic potential of marine actinobacteria. The genomes of two marine actinomycetes Brevibacterium luteolum MOSEL-ME10a and Cellulosimicrobium funkei MOSEL-ME6 were sequenced to identify the biosynthetic gene clusters (BGCs). Additionally, anti-proliferative, antioxidant, and enzyme inhibitory activities were studied in vitro. We report a total genome size of 2.77 Mb with GC content of 67.8% and 6.81 Mb with GC content of 69% for Brevibacterium sp. MOSEL-ME10a and Cellulosimicrobium sp. MOSEL-ME6, respectively. Biosynthetic gene clusters (BGCs) encoding different classes of natural products were predicted including terpenes, peptides, siderophores, ectoines, and bacteriocins. The bioactivity potential of crude extracts derived from these strains was evaluated. Notable anti-proliferative activity was observed against HepG2 cell line (hepatocellular carcinoma) with an IC50 value of 182 µg/mL for Brevibacterium sp. MOSEL-ME10a. Furthermore, antioxidant activity was assessed with IC50 values of 48.91 µg/mL and 102.5 µg/mL for Brevibacterium sp. MOSEL-ME10a and Cellulosimicrobium sp. MOSEL-ME6, respectively. Protein kinase inhibition potential was observed only for Brevibacterium sp. MOSEL-ME10a. Our study also reports lower amylase enzyme inhibition potential for both strains. Moreover, both crude extracts showed only slight-to-no toxic effect on erythrocytes at 400 µg/mL and below, indicating erythrocyte membrane stability. Our data present the genomic features revealing biosynthetic potential of marine actinobacteria as well as biological activities found in vitro.


Assuntos
Actinobacteria/genética , Actinobacteria/metabolismo , Brevibacterium/genética , Brevibacterium/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Genoma Bacteriano/genética , Humanos , Família Multigênica , Filogenia , Análise de Sequência de DNA
11.
Arch Microbiol ; 203(5): 2291-2296, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33649904

RESUMO

Two bacterial strains, designated REN4T and REN4-1, were isolated from daqu sample collected from baijiu factory located in Shanxi, China. The two strains shared highly similar 16S rRNA gene sequences (99.67% identities) and formed a monophyletic clade within the Brevibacterium 16S rRNA gene tree, showing 97.56-97.85% 16S rRNA gene sequence identities with type strains Brevibacterium permense VKM Ac-2280 T, Brevibacterium sediminis FXJ8.269 T, Brevibacterium oceani BBH7T and Brevibacterium epidermidis NCIMB 702286 T. They contained MK-8(H2) as the most predominant menaquinone, antesio-C15:0, antesio-C17:0, Iso-C16:0 and Iso-C17:0 as the major cellular fatty acids, DPG (diphosphatidylglycerol), PG (phosphatidylglycerol), PGL (phosphatidylglycerollipids), and PL (phospholipids) as the main polar lipids. The genomic DNA G + C content of strains REN4 and REN4-1 were 64.35, 65.82 mol%. Moreover, the low DNA-DNA relatedness values, physiological and biochemical characteristics, and taxonomic analysis allowed the differentiation of strains REN4T and REN4-1 from the other recognized species of the genus Brevibacterium. Therefore, strain REN4T represents a novel species of the genus Brevibacterium, for which the name Brevibacterium renqingii sp. nov. is proposed, with the type strain REN4T (= JCM 33953 T = KCTC 49366 T).


Assuntos
Brevibacterium , /microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , Brevibacterium/classificação , Brevibacterium/genética , Brevibacterium/isolamento & purificação , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Fermentação , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Int J Biol Macromol ; 172: 360-370, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33460659

RESUMO

Though numerous proteases have been isolated and screened for the dehairing purpose, their use in the leather industry is limited mainly due to high cost, the need for expertise, and control during unit operation and alterations in the quality of leather due to lack of the right kind of substrate specificity of the enzymes used. This paper deals with the comparative specificity and dehairing efficiency of proteases isolated from Bacillus cereus VITSP01 (PE2) and Brevibacterium luteolum VITSP02 (PE). PE2 and PE were found to be trypsin-like and elastase-like serine proteases respectively. The protease of VITSP02 degraded the proteoglycans efficiently in comparison to that of VITSP01. The results suggest that the possible targets of the studied proteases might be skin proteoglycans, including those cementing the hair root bulb. Hence, an in-depth study on the substrate specificity of the dehairing proteases would help in designing an improved screening method for isolating potent dehairing enzymes.


Assuntos
Proteínas de Bactérias/química , Cabelo/efeitos dos fármacos , Proteoglicanas/química , Serina Proteases/química , Pele/efeitos dos fármacos , Matadouros , Animais , Bacillus cereus/química , Bacillus cereus/enzimologia , Proteínas de Bactérias/isolamento & purificação , Brevibacterium/química , Brevibacterium/enzimologia , Ensaios Enzimáticos , Cabras , Cabelo/química , Cinética , Serina Proteases/isolamento & purificação , Pele/química , Especificidade por Substrato
13.
J Hazard Mater ; 408: 124943, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33385730

RESUMO

The application of biosurfactants for the degradation of various toxic compounds has received much attention among researchers worldwide. A stimulated degrading method was carried out in this research to determine the efficiency of surfactant on the biodegradation of aromatic amine 4-Aminobiphenyl (4-ABP). The biosurfactant mediated process is an alternative strategy for chemical surfactants because chemical surfactants are toxic and nonbiodegradable. The bacterium was isolated through the enrichment process and identified using 16S rRNA sequencing method. The molecular characterization showed that the isolate belongs to Brevibacterium casei-4AB. Biosurfactant produced in this study was examined through screening activities like oil spreading, emulsification activity and surface tension measurement. Instrumental characterization like Fourier Transform Infrared Spectrophotometer (FT-IR) results suggested that there is a presence of NH group, aliphatic hydrocarbons, ester groups, amide and alkenes and further Gas chromatography- Mass Spectrometry (GC-MS) results confirmed the presence of fatty acids such as Hexadecanoic and Octadecadienoic acid which showed that the produced surfactant is lipopeptide. Protein content and lipid content in the biosurfactant was found to be 18 ± 0.8% and 30 ± 0.1%. The degraded metabolites of 4-ABP were analyzed through the GC-MS process which revealed the presence of metabolites such as 5-Amino-2-methoxy phenol.


Assuntos
Lipopeptídeos , Tensoativos , Aminas , Biodegradação Ambiental , Brevibacterium , RNA Ribossômico 16S/genética , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Curr Microbiol ; 78(2): 688-695, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33399943

RESUMO

Brevibacterium linens AE038-8 is an arsenic hyper-tolerant bacterial strain, previously isolated from well water in Tucumán, Argentina. The aim of this study was to characterize this strain regarding its resistance to different stress factors and to evaluate its antiviral activity against Herpes simplex virus type 1 (HSV-1). We found that B. linens AE038-8 was capable of tolerating high concentrations of heavy metals such as Cd(II), Cr(VI) and Cu(II). When grown in the presence of NaCl, it could tolerate up to 3 M in LB25 medium. When cultivated, B. linens released to the supernatants a bioactive principle with antiviral activity against HSV-1 virus regardless growth conditions.


Assuntos
Brevibacterium , Herpesvirus Humano 1 , Antivirais/farmacologia , Argentina
15.
Lasers Med Sci ; 36(6): 1249-1260, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33079312

RESUMO

In the last few decades, there has essentially been an explosion in the use of lasers in medicine, especially in the area of cosmetic dermatology. Potentially harmful substances are liberated when tissues are vaporized with laser. This creates numerous risks, including the spread of infectious disease. Smoke evacuators are devices that capture and filter laser plume, thereby maintaining a safe environment for the surgical team and patient. Our aim was to characterize the microbial community structure within the suction tube and funnel of the smoke evacuator system, identify their origin, and evaluate pathogenicity. Dust particles were collected from the instruments with a cotton swab. DNA was extracted from the swabs and the transport media, and sequencing was performed using the Illumina HiSeq Xplatform. Metagenomic analysis was conducted using the Empowering the Development of Genomics Expertise (EDGE) Bioinformatics pipeline and custom Python scripts. The most abundant bacterial species were Micrococcus luteus and Brevibacterium casei in the suction tube, and Dermacoccus sp. Ellin 185 and Janibacter hoylei in the suction funnel. A total of 15 medium- to high-quality metagenome-assembled genomes (MAGs) were constructed where we found 104 antibiotic-resistant genes (ARGs) and 741 virulence factors. Findings indicate that the suction tube and funnel are likely a reservoir of virulence factor genes and ARGs, which can possibly be passed on to other bacteria via horizontal gene transfer. We would like to emphasize the health risk these microorganisms pose and the need to reevaluate the current hygiene standards with regard to the smoke evacuator system.


Assuntos
Metagenoma , Actinobacteria , Brevibacterium , Poeira , Humanos , Terapia a Laser/instrumentação , Fumaça , Sucção/instrumentação
16.
Folia Microbiol (Praha) ; 66(2): 189-196, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33131029

RESUMO

In the present study, bacterial isolates were screened for arsenic resistance efficiency. Environmental isolates were isolated from arsenic-rich soil samples (i.e., from Rajnandgaon district of Chhattisgarh state, India). Amplification and sequencing of 16S rRNA gene revealed that the isolates were of Bacillus firmus RSN1, Brevibacterium senegalense RSN2, Enterobacter cloacae RSN3, Stenotrophomonas pavanii RSN6, Achromobacter mucicolens RSN7, and Ochrobactrum intermedium RSN10. Arsenite efflux gene (arsB) was successfully amplified in E. cloacae RSN3. Atomic absorption spectroscopy (AAS) analysis showed an absorption of 32.22% arsenic by the RSN3 strain. Furthermore, results of scanning electron microscopy (SEM) for morphological variations revealed an initial increase in the cell size at 1 mM sodium arsenate; however, it was decreased at 10 mM concentration in comparison to control. This change of the cell size in different metal concentrations was due to the uptake and expulsion of the metal from the cell, which also confirmed the arsenite efflux system.


Assuntos
Arsênio , Poluentes do Solo , Achromobacter , Brevibacterium , Enterobacter cloacae/genética , Ochrobactrum , RNA Ribossômico 16S/genética , Solo , Stenotrophomonas
17.
Microb Pathog ; 150: 104693, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33352215

RESUMO

The alternative antimicrobial strategies that mitigate the threat of antibiotic resistance is the quorum-sensing inhibition (QSI) mechanism, which targets autoinducer dependent virulence gene expression in bacterial pathogens. N-acyl homoserine lactone (AHL) acts as a key regulator in the production of virulence factors and biofilm formation in Pseudomonas aeruginosa PAO1 and violacein pigment production in Chromobacterium violaceum ATCC 12472. In the present study, the marine sponge Haliclona fibulata symbiont Brevibacterium casei strain Alu 1 showed potential QSI activity in a concentration-dependent manner (0.5-2% v/v) against the N-acyl homoserine lactone (AHL)-mediated violacein production in C. violaceum (75-95%), and biofilm formation (53-96%), protease (27-82%), pyocyanin (82-95%) and pyoverdin (29-38%) productions in P. aeruginosa. Further, the microscopic analyses validated the antibiofilm activity of the cell-free culture supernatant (CFCS) of B. casei against P. aeruginosa. Subsequently, the biofilm and pyoverdin inhibitory efficacy of the ethyl acetate extract of B. casei CFCS was assessed against P. aeruginosa. Further, the gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of variety of components in which diethyl phthalate was found to be a major active component. This phthalate ester, known as diethyl ester of phthalic acid, could act as a potential therapeutic agent for preventing bacterial biofilm and virulence associated infectious diseases.


Assuntos
Poríferos , Percepção de Quorum , Animais , Antibacterianos/farmacologia , Biofilmes , Brevibacterium , Chromobacterium , Pseudomonas aeruginosa , Virulência
18.
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
19.
Indian J Med Microbiol ; 38(2): 226-228, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32883940

RESUMO

Brevibacteria are a part of the normal skin flora and may be dismissed in blood cultures as contaminants. They have been reported as opportunistic pathogens in immunocompromised patients. We report a catheter-related bloodstream infection with Brevibacterium casei in a 6-year-old child with aplastic anaemia. Treatment with appropriate antibiotics along with the removal of the catheter resulted in complete cure in our patient.


Assuntos
Anemia Aplástica/complicações , Bacteriemia/complicações , Brevibacterium/isolamento & purificação , Infecções Relacionadas a Cateter/complicações , Infecções por Bactérias Gram-Positivas/complicações , Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Cateteres de Demora , Criança , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Hospedeiro Imunocomprometido , Masculino
20.
Int J Syst Evol Microbiol ; 70(11): 5818-5823, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32965208

RESUMO

A new Gram-stain-positive, aerobic, non-motile and rod-shaped actinobacterium, designated O1T, was isolated from a deep-sea sediment of the Western Pacific Ocean. Strain O1T showed optimal growth at 30 °C, between pH 6.0 and 8.0, and in the presence of 1-5 % (w/v) NaCl. The predominant menaquinone was MK-8 (H2), and anteiso-C15 : 0 and anteiso-C17 : 0 were the major fatty acids. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and one unknown glycolipid. The DNA G+C content of strain O1T was 64.9 mol% and the genome size was 4.17 Mb. Based on a similarity search and phylogenetic analysis of the 16S rRNA gene sequence, strain O1T belonged to the genus Brevibacterium. The values of average nucleotide identity and in silico DNA-DNA hybridization between strain O1T and its close relatives were well below the thresholds used for the delineation of a new species. On the basis of the morphological and chemotaxonomic characteristics, as well as the genotypic data, it is proposed that strain O1T represents a novel species of the genus Brevibacterium, for which the name Brevibacterium profundi sp. nov. is proposed. The type strain is O1T (=JCM 33845T=MCCC 1A16744T).


Assuntos
Brevibacterium/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Brevibacterium/isolamento & purificação , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Tamanho do Genoma , Hibridização de Ácido Nucleico , Oceano Pacífico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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