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1.
PLoS One ; 16(9): e0257449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34529734

RESUMO

Despite the formation of biofilms on catheters for extracorporeal membrane oxygenation (ECMO), some patients do not show bacteremia. To elucidate the specific linkage between biofilms and bacteremia in patients with ECMO, an improved understanding of the microbial community within catheter biofilms is necessary. Hence, we aimed to evaluate the biofilm microbiome of ECMO catheters from adults with (n = 6) and without (n = 15) bacteremia. The microbiomes of the catheter biofilms were evaluated by profiling the V3 and V4 regions of bacterial 16s rRNA genes using the Illumina MiSeq sequencing platform. In total, 2,548,172 reads, with an average of 121,341 reads per sample, were generated. Although alpha diversity was slightly higher in the non-bacteremic group, the difference was not statistically significant. In addition, there was no difference in beta diversity between the two groups. We found 367 different genera, of which 8 were present in all samples regardless of group; Limnohabitans, Flavobacterium, Delftia, Massilia, Bacillus, Candidatus, Xiphinematobacter, and CL0-1 showed an abundance of more than 1% in the sample. In particular, Arthrobacter, SMB53, Neisseria, Ortrobactrum, Candidatus Rhabdochlamydia, Deefgae, Dyella, Paracoccus, and Pedobacter were highly abundant in the bacteremic group. Network analysis indicated that the microbiome of the bacteremic group was more complex than that of the non-bacteremic group. Flavobacterium and CL0.1, which were abundant in the bacteremic group, were considered important genera because they connected different subnetworks. Biofilm characteristics in ECMO catheters varied according to the presence or absence of bacteremia. There were no significant differences in diversity between the two groups, but there were significant differences in the community composition of the biofilms. The biofilm-associated community was dynamic, with the bacteremic group showing very complex network connections within the microbiome.


Assuntos
Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/microbiologia , Oxigenação por Membrana Extracorpórea/instrumentação , Microbiota , Arthrobacter/genética , Arthrobacter/isolamento & purificação , Arthrobacter/fisiologia , Bacteriemia/patologia , Bactérias/genética , Bactérias/isolamento & purificação , Biofilmes , Infecções Relacionadas a Cateter/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neisseria/genética , Neisseria/isolamento & purificação , Neisseria/fisiologia , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Estudos Retrospectivos
2.
Biotechnol Lett ; 43(10): 1989-1999, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34392452

RESUMO

OBJECTIVES: In our previous study, citrate was used as auxiliary energy substance for improving cAMP fermentation performance, however, the regulation mechanism of citrate on improved cAMP contents was not clear. To elucidate the regulation mechanism, cAMP fermentations with/without citrate addition were conducted in a 7 L fermentor using Arthrobacter sp. CCTCC 2013431 and assays on key enzymes activities, energy metabolism level, amino acids contents and peroxidation level were performed. RESULTS: With 3 g/L-broth sodium citrate added, cAMP concentration and conversion yield from glucose reached 4.34 g/L and 0.076 g/g which were improved by 30.7% and 29.8%, respectively, when compared with those of control. Citrate changed carbon flux distribution among different routes and more carbon flux was directed into pentose phosphate pathway beneficial to cAMP synthesis. Meanwhile, energy metabolism together with precursor amino acids levels were improved significantly owing to strengthened metabolic intensity of tricarboxylate cycle by exogenous citrate utilization which provided energy and substance basis for cAMP production. Moreover, higher glutamate synthesis and oxidative stress caused by citrate addition consumed excessive NADPH derived from pentose phosphate pathway by which feedback suppression for pentose phosphate pathway was relieved efficiently. CONCLUSION: Citrate promoted cAMP fermentation production by Arthrobacter sp. CCTCC 2013431 due to enhanced precursor amino acids, energy metabolism level and relieved feedback suppression for pentose phosphate pathway.


Assuntos
Aminoácidos/metabolismo , Arthrobacter , Ácido Cítrico/metabolismo , AMP Cíclico , Arthrobacter/metabolismo , Arthrobacter/fisiologia , Reatores Biológicos/microbiologia , Meios de Cultura/química , Meios de Cultura/metabolismo , AMP Cíclico/análise , AMP Cíclico/metabolismo , Metabolismo Energético/fisiologia , Estresse Oxidativo/fisiologia
3.
Microb Ecol ; 81(2): 471-482, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32901388

RESUMO

The pine engraver beetle, Ips acuminatus Gyll, is a bark beetle that causes important damages in Scots pine (Pinus sylvestris) forests and plantations. As almost all higher organisms, Ips acuminatus harbours a microbiome, although the role of most members of its microbiome is not well understood. As part of a work in which we analysed the bacterial diversity associated to Ips acuminatus, we isolated the strain Arthrobacter sp. IA7. In order to study its potential role within the bark beetle holobiont, we sequenced and explored its genome and performed a pan-genome analysis of the genus Arthrobacter, showing specific genes of strain IA7 that might be related with its particular role in its niche. Based on these investigations, we suggest several potential roles of the bacterium within the beetle. Analysis of genes related to secondary metabolism indicated potential antifungal capability, confirmed by the inhibition of several entomopathogenic fungal strains (Metarhizium anisopliae CCF0966, Lecanicillium muscarium CCF6041, L. muscarium CCF3297, Isaria fumosorosea CCF4401, I. farinosa CCF4808, Beauveria bassiana CCF4422 and B. brongniartii CCF1547). Phylogenetic analyses of the 16S rRNA gene, six concatenated housekeeping genes (tuf-secY-rpoB-recA-fusA-atpD) and genome sequences indicated that strain IA7 is closely related to A. globiformis NBRC 12137T but forms a new species within the genus Arthrobacter; this was confirmed by digital DNA-DNA hybridization (37.10%) and average nucleotide identity (ANIb) (88.9%). Based on phenotypic and genotypic features, we propose strain IA7T as the novel species Arthrobacter ipsi sp. nov. (type strain IA7T = CECT 30100T = LMG 31782T) and suggest its protective role for its host.


Assuntos
Arthrobacter/fisiologia , Besouros/microbiologia , Genoma Bacteriano/genética , Casca de Planta/parasitologia , Animais , Antibiose , Arthrobacter/classificação , Arthrobacter/genética , DNA Bacteriano/genética , Fungos/crescimento & desenvolvimento , Genes Bacterianos/genética , Interações entre Hospedeiro e Microrganismos , Fenótipo , Filogenia , Pinus/parasitologia , Doenças das Plantas/parasitologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Sci Rep ; 9(1): 1792, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30741989

RESUMO

It is commonly accepted that bacteria actively interact with plant host and have beneficial effects on growth and adaptation and grant tolerance to various biotic and abiotic stresses. However, the mechanisms of plant growth promoting bacteria to communicate and adapt to the plant environment are not well characterized. Among the examined bacteria isolates from different saline soils, Arthrobacter nitroguajacolicus was selected as the best plant growth-promoting bacteria under salt stress. To study the effect of bacteria on wheat tolerance to salinity stress, bread wheat seeds were inoculated with A. nitroguajacolicus and grown under salt stress condition. Comparative transcriptome analysis of inoculated and un-inoculated wheat roots under salt stress showed up-regulation of 152 genes whereas 5 genes were significantly down-regulated. Many genes from phenylpropanoid, flavonoid and terpenoid porphyrin and chlorophyll metabolism, stilbenoid, diarylheptanoid metabolism pathways were differentially expressed within inoculated roots under salt stress. Also, a considerable number of genes encoding secondary metabolites such as phenylpropanoids was detected. They are known to take part in lignin biosynthesis of the cell wall as well as antioxidants.


Assuntos
Arthrobacter/fisiologia , Raízes de Plantas/fisiologia , Estresse Salino/fisiologia , Transcrição Gênica , Triticum/fisiologia , Genes de Plantas , Raízes de Plantas/metabolismo , Tolerância ao Sal , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Regulação para Cima
5.
Mol Biol Rep ; 46(1): 133-141, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30374769

RESUMO

Urease is a potent metalloenzyme with diverse applications. This paper describes the scale up and purification of an extracellular urease from Arthrobacter creatinolyticus MTCC 5604. The urease production was scaled-up in 3.7 L and 20 L fermentor. A maximum activity of 27 and 27.8 U/mL and a productivity of 0.90 and 0.99 U/mL/h were obtained at 30 h and 28 h in 3.7 and 20 L fermentor, respectively. Urease was purified to homogeneity with 49.85-fold purification by gel filtration and anion exchange chromatography with a yield of 36% and a specific activity of 1044.37 U/mg protein. The enzyme showed three protein bands with molecular mass of 72.6, 11.2 and 6.1 kDa on SDS-PAGE and ~ 270 kDa on native PAGE. The cytotoxic effect of urease was assessed in vitro using cancer cell lines (A549 and MG-63) and normal cell line (HEK 293). Urease showed its inhibitory effects on cancer cell lines through the generation of toxic ammonia, which in turn increased the pH of the surrounding medium. This increase in extracellular pH, enhanced the cytotoxic effect of weak base chemotherapeutic drugs, doxorubicin (50 µM) and vinblastine (100 µM) in the presence of urease (5 U/mL) and urea (0-4 mM) significantly.


Assuntos
Arthrobacter/enzimologia , Urease/isolamento & purificação , Urease/farmacologia , Células A549/efeitos dos fármacos , Amônia/metabolismo , Arthrobacter/metabolismo , Arthrobacter/fisiologia , Linhagem Celular , Cromatografia em Gel/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Peso Molecular , Ureia/metabolismo , Urease/fisiologia
6.
Extremophiles ; 21(6): 1057-1067, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28993922

RESUMO

This research aimed to investigate the viability and biodiversity of microbial communities within ancient Arctic permafrost after exposure to a gamma-radiation dose of 100 kGy at low temperature (- 50 °C), low pressure (1 Torr) and dehydration conditions. The main objective was to assess the possibility for long-term survival of Earth-bound microorganisms in the subsurface of Martian regolith or inside small space bodies at constant absorption and accumulation of the gamma radiation dose. Investigated microbial communities had shown high resistance to a simulated Martian environment. After irradiation the total count of prokaryotic cells and number of metabolically active bacterial cells remained at the control level, while the number of bacterial CFUs decreased by 2 orders of magnitude, and the number of metabolically active cells of archaea decreased threefold. Besides, the abundance of culturable bacteria after irradiation was kept at a high level: not less than 3.7 × 105 cells/g. Potential metabolic activity of irradiated microbial communities in general were higher than in the control sample. A fairly high biodiversity of bacteria was detected in the exposed sample of permafrost, although the microbial community structure underwent significant changes after irradiation. In particular, actinobacteria populations of the genus Arthrobacter, which was not revealed in the control samples, became predominant in bacterial communities following the exposure. The results of the study testify that long-term preservation of microbial life inside Martian permafrost is possible. The data obtained can also be evaluated from the perspective of the potential for discovering viable Earth-bound microorganisms on other objects in the Solar system and inside of small bodies in outer space.


Assuntos
Meio Ambiente Extraterreno , Microbiota , Pergelissolo/microbiologia , Tolerância a Radiação , Aclimatação , Archaea/isolamento & purificação , Archaea/fisiologia , Archaea/efeitos da radiação , Regiões Árticas , Arthrobacter/isolamento & purificação , Arthrobacter/fisiologia , Arthrobacter/efeitos da radiação , Raios gama , Marte
7.
J Environ Sci Health B ; 52(10): 745-751, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28976238

RESUMO

This work was aimed at studying the response of soil non-spore-forming actinobacterial strain Arthrobacter agilis Lush 13 to changing natural conditions, such as nutrient availability and the presence of degradable and recalcitrant aliphatic and aromatic substrates. The A. agilis strain Lush13 was able to degrade octane, nonane, hexadecane, benzoate, phenol, and 2,3-, 2,4-, 2,5-, 2,6-dichlorophenols, but not grew on 3,4-dichlorophenol, 2,3,4-, 2,4,5-, 2,4,6-trichlorophenol (TCP), pentachlorophenol (PCP), 2-chlorobenzoate, 3-chlorobenzoate, 3,5-dichlorobenzoate, 2,4-dichlorobenzoate. Under growth-arresting conditions due to nitrogen- or multiple starvation or recalcitrant (non-utilizable) carbon source, the studied strain preserved viability for prolonged periods (4-24 months) due to transition to dormancy in the form of conglomerated small and ultrasmall cyst-like dormant cells (CLC). Dormant cells were shown to germinate rapidly (30 min or later) after removal of starvation stress, and this process was followed by breakdown of conglomerates with the eliberation and further division of small multiple actively growing daughter cells. Results of this study shed some light to adaptive capabilities of soil arthrobacters in pure and polluted environments.


Assuntos
Arthrobacter/fisiologia , Hidrocarbonetos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Carbono/metabolismo , Clorobenzoatos/metabolismo , Clorofenóis/metabolismo , Nitrogênio/metabolismo , Pentaclorofenol/metabolismo , Microbiologia do Solo
8.
Jpn J Infect Dis ; 70(2): 201-202, 2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27357988

RESUMO

An 87-year-old man with poorly controlled diabetic mellitus presented with fever, bedsores, and elevated hepatobiliary enzyme levels. He was diagnosed with bacteremia with acute cholangitis due to Arthrobacter species, which are Gram-positive, aerobic, catalase-positive, coryneform bacteria belonging to the family Microbacteriaceae. Doripenem and subsequencial sulbactam/ampicillin treatment were used for the acute cholangitis, and the bacteremia was treated with a 2-week course of vancomycin. The bacteremia was misidentified by the phenotyping assay (API Coryne test), but was identified as Arthrobacter creatinolyticus by 16S rRNA and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry. To our knowledge, this is the first report of a human case of A. creatinolyticus bacteremia.


Assuntos
Arthrobacter/isolamento & purificação , Bacteriemia/diagnóstico , Colangite/diagnóstico , Complicações do Diabetes/diagnóstico , Complicações do Diabetes/patologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Aerobiose , Idoso de 80 Anos ou mais , Ampicilina/administração & dosagem , Antibacterianos/administração & dosagem , Arthrobacter/classificação , Arthrobacter/genética , Arthrobacter/fisiologia , Bacteriemia/microbiologia , Bacteriemia/patologia , Carbapenêmicos/administração & dosagem , Colangite/complicações , Colangite/microbiologia , Colangite/patologia , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Doripenem , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/patologia , Humanos , Masculino , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sulbactam/administração & dosagem , Inibidores de beta-Lactamases/administração & dosagem
9.
ISME J ; 11(1): 67-77, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27518809

RESUMO

Manganese (Mn) is an important metal in geochemical cycles. Some microorganisms can oxidize Mn(II) to Mn oxides, which can, in turn, affect the global cycles of other elements by strong sorption and oxidation effects. Microbe-microbe interactions have important roles in a number of biological processes. However, how microbial interactions affect Mn(II) oxidation still remains unknown. Here, we investigated the interactions between two bacteria (Arthrobacter sp. and Sphingopyxis sp.) in a co-culture, which exhibited Mn(II)-oxidizing activity, although neither were able to oxidize Mn(II) in isolation. We demonstrated that the Mn(II)-oxidizing activity in co-culture was most likely induced via contact-dependent interactions. The expressed Mn(II)-oxidizing protein in the co-culture was purified and identified as a bilirubin oxidase belonging to strain Arthrobacter. Full sequencing of the bilirubin oxidase-encoding gene (boxA) was performed. The Mn(II)-oxidizing protein and the transcripts of boxA were detected in the co-culture, but not in either of the isolated cultures. This indicate that boxA was silent in Arthrobacter monoculture, and was activated in response to presence of Sphingopyxis in the co-culture. Further, transcriptomic analysis by RNA-Seq, extracellular superoxide detection and cell density quantification by flow cytometry indicate induction of boxA gene expression in Arthrobacter was co-incident with a stress response triggered by co-cultivation with Sphingopyxis. Our findings suggest the potential roles of microbial physiological responses to stress induced by other microbes in Mn(II) oxidation and extracellular superoxide production.


Assuntos
Arthrobacter/fisiologia , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Manganês/metabolismo , Interações Microbianas , Sphingomonadaceae/fisiologia , Arthrobacter/genética , Proteínas de Bactérias/metabolismo , Oxirredução , Sphingomonadaceae/genética
10.
Int J Phytoremediation ; 19(3): 281-289, 2017 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-27593491

RESUMO

Four plant growth-promoting bacteria (PGPB) were used as study materials, among them two heavy metal-tolerant rhizosphere strains SrN1 (Arthrobacter sp.) and SrN9 (Bacillus altitudinis) were isolated from rhizosphere soil, while two endophytic strains SaN1 (Bacillus megaterium) and SaMR12 (Sphingomonas) were identified from roots of the cadmium (Cd)/zinc (Zn) hyperaccumulator Sedum alfredii Hance. A pot experiment was carried out to investigate the effects of these PGPB on plant growth and Cd accumulation of oilseed rape (Brassica napus) plants grown on aged Cd-spiked soil. The results showed that the four PGPB significantly boosted oilseed rape shoot biomass production, improved soil and plant analyzer development (SPAD) value, enhanced Cd uptake of plant and Cd translocation to the leaves. By fluorescent in situ hybridization (FISH) and green fluorescent protein (GFP), we demonstrated the studied S. alfredii endophytic bacterium SaMR12 were able to colonize successfully in the B. napus roots. However, all four PGPB could increase seed Cd accumulation. Due to its potential to enhance Cd uptake by the plant and to restrict Cd accumulation in the seeds, SaMR12 was selected as the most promising microbial partner of B. napus when setting up a plant-microbe fortified remediation system.


Assuntos
Bactérias/metabolismo , Brassica napus/metabolismo , Cádmio/metabolismo , Sedum/microbiologia , Poluentes do Solo/metabolismo , Arthrobacter/fisiologia , Bacillus/fisiologia , Bactérias/classificação , Biodegradação Ambiental , Endófitos/fisiologia , Raízes de Plantas/microbiologia , Rizosfera , Sementes/metabolismo , Sphingomonas/fisiologia
11.
Rev Argent Microbiol ; 48(4): 342-346, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-27916328

RESUMO

Arthrobacter agilis UMCV2 is a rhizosphere bacterium that promotes legume growth by solubilization of iron, which is supplied to the plant. A second growth promotion mechanism produces volatile compounds that stimulate iron uptake activities. Additionally, A. agilis UMCV2 is capable of inhibiting the growth of phytopathogens. A combination of quantitative polymerase chain reaction and fluorescence in situ hybridization techniques were used here to detect and quantify the presence of the bacterium in the internal tissues of the legume Medicago truncatula. Our results demonstrate that A. agilis UMCV2 behaves as an endophytic bacterium of M. truncatula, particularly in environments where iron is available.


Assuntos
Arthrobacter/fisiologia , Endófitos/fisiologia , Medicago/microbiologia , Inoculantes Agrícolas , Arthrobacter/genética , Arthrobacter/isolamento & purificação , Meios de Cultura , DNA Bacteriano/análise , Endófitos/genética , Endófitos/isolamento & purificação , Compostos Ferrosos/administração & dosagem , Ferro/metabolismo , Medicago/crescimento & desenvolvimento , Medicago/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Rizosfera , Simbiose
12.
Int J Phytoremediation ; 18(10): 956-65, 2016 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-27159623

RESUMO

The growth and metal-extraction efficiency of plants when exposed to toxic metals can be enhanced by inoculating with certain bacteria, but the mechanisms of this process remain unclear. We report results from glasshouse experiments on the effect of Arthrobacter echigonensis MN1405 in promoting Phytolacca acinosa Roxb. growth when exposed to 100 mg/L Mn solution. Mn removal efficiency in solution was significantly enhanced by bacterial inoculation; Mn was accumulated in the root of P. acinosa Roxb. plant. The bacteria oxidized the Mn on root surface, which formed a Mn plaque to serve as a barrier or a containment to prevent metal toxicity. In this process, pH condition was an important factor on the effects of microbial-assisted heavy metal phytoremediation. Our finding suggests that A. echigonensis MN1405 assisted P. acinosa to achieve high remediation efficiency of Mn removal and accumulation in Mn contamination area.


Assuntos
Arthrobacter/fisiologia , Biodegradação Ambiental , Manganês/metabolismo , Phytolacca/fisiologia , Poluentes do Solo/metabolismo , Phytolacca/crescimento & desenvolvimento , Phytolacca/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Simbiose
13.
Int J Phytoremediation ; 18(11): 1113-21, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27196364

RESUMO

Salt-induced soil degradation is common in farmlands and limits the growth and development of numerous crop plants in the world. In this study, we isolated salt-tolerant bacteria from the rhizosphere of Tamarix chinensis, Suaeda salsa and Zoysia sinica, which are common wild plants grown on a saline-alkaline land, to test these bacteria's efficiency in alleviating salt stress in tomato plants. We screened out seven strains (TF1-7) that are efficient in reducing salt stress in tomato seedlings. The sequence data of 16S rRNA genes showed that these strains belong to Arthrobacter and Bacillus megaterium. All strains could hydrolyze casein and solubilize phosphate, and showed at least one plant growth promotion (PGP)-related gene, indicating their potential in promoting plant growth. The Arthrobacter strains TF1 and TF7 and the Bacillus megaterium strain TF2 and TF3 could produce indole acetic acid under salt stress, further demonstrating their PGP potential. Tomato seed germination, seedling length, vigor index, and plant fresh and dry weight were enhanced by inoculation of Arthrobacter and B. megaterium strains under salt stress. Our results demonstrated that salt-tolerant bacteria isolated from the rhizosphere of wild plants grown on saline-alkaline lands could be used for alleviating salt stress in crop plants.


Assuntos
Arthrobacter/fisiologia , Bacillus megaterium/fisiologia , Rizosfera , Microbiologia do Solo , Solanum lycopersicum/microbiologia , Solanum lycopersicum/fisiologia , Chenopodiaceae/microbiologia , Poaceae/microbiologia , Salinidade , Plântula/microbiologia , Plântula/fisiologia , Solo/química , Estresse Fisiológico , Tamaricaceae/microbiologia
14.
J Biotechnol ; 222: 23-4, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-26854946

RESUMO

Arthrobacter strain A3, a psychotrophic bacterium isolated from the Tian Shan Mountain of China, can degrade the cellulose and synthesis the long-chain hydrocarbons efficiently in low temperature. Here we report the complete genome sequence of this bacterium. The complete genome sequence of Arthrobacter strain A3, consisting of a cycle chromosome with a size of 4.26 Mbp and a cycle plasmid with a size of 194kbp. In this genome, a hydrocarbon biosynthesis gene cluster (oleA, oleB/oleC and oleD) was identified. To resistant the extreme environment, this strain contains a unique mycothiol-biosynthetic pathway (mshA-D), which has not been found in other Arthrobacter species before. The availability of this genome sequence allows us to investigate the genetic basis of adaptation to growth in a nutrient-poor permafrost environment and to evaluate of the biofuel-synthetic potential of this species.


Assuntos
Arthrobacter , Genoma Bacteriano/genética , Hidrocarbonetos/metabolismo , Arthrobacter/genética , Arthrobacter/metabolismo , Arthrobacter/fisiologia , Família Multigênica/genética
15.
Rev Argent Microbiol ; 47(3): 219-28, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26350556

RESUMO

The kingdom Fungi is represented by a large number of organisms, including pathogens that deteriorate the main structural components of wood, such as cellulose, hemicellulose and lignin. The aim of our work was to characterize the antifungal activity in Arthrobacter agilis UMCV2 and diverse amines against wood-decaying fungi. Four fungal organisms (designated as UMTM) were isolated from decaying wood samples obtained from a forest in Cuanajo-Michoacán, México. Two of them showed a clear enzymatic activity of cellulases, xylanases and oxido-reducing enzymes and were identified as Hypocrea (UMTM3 isolate) and Fusarium (UMTM13 isolate). In vitro, the amines showed inhibitory effect against UMTM growth and one of the amines, dimethylhexadecylamine (DMA16), exhibited strong potential as wood preventive treatment, against the attack of decaying fungi.


Assuntos
Aminas/farmacologia , Antibiose , Arthrobacter/fisiologia , Fusarium/crescimento & desenvolvimento , Hypocrea/crescimento & desenvolvimento , Madeira/microbiologia , Proteínas Fúngicas/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , Fusarium/efeitos dos fármacos , Fusarium/enzimologia , Fusarium/isolamento & purificação , Hypocrea/efeitos dos fármacos , Hypocrea/enzimologia , Hypocrea/isolamento & purificação , México , Micélio/enzimologia , Técnicas de Tipagem Micológica , Pinus/microbiologia
16.
J Biotechnol ; 214: 139-40, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26415659

RESUMO

We report the complete genome sequence of Arthrobacter sp. ERGS1:01, a novel bacterium which produces industrial enzymes at low temperature. East Rathong glacier in Sikkim Himalayas is untouched and unexplored for microbial diversity though it has a rich source of glaciers, alpine and meadows. Genome sequence has provided the basis for understanding its adaptation under harsh condition of Himalayan glacier, its ability to produce cold active industrial enzymes and has unlocked opportunities for microbial bioprospection from East Rathong glacier.


Assuntos
Arthrobacter/enzimologia , Arthrobacter/genética , Genoma Bacteriano/genética , Arthrobacter/fisiologia , Temperatura Baixa , Camada de Gelo/microbiologia , Índia , Microbiologia Industrial
17.
Appl Environ Microbiol ; 81(19): 6915-25, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26209676

RESUMO

The mucosal surfaces of wild and farmed aquatic vertebrates face the threat of many aquatic pathogens, including fungi. These surfaces are colonized by diverse symbiotic bacterial communities that may contribute to fight infection. Whereas the gut microbiome of teleosts has been extensively studied using pyrosequencing, this tool has rarely been employed to study the compositions of the bacterial communities present on other teleost mucosal surfaces. Here we provide a topographical map of the mucosal microbiome of an aquatic vertebrate, the rainbow trout (Oncorhynchus mykiss). Using 16S rRNA pyrosequencing, we revealed novel bacterial diversity at each of the five body sites sampled and showed that body site is a strong predictor of community composition. The skin exhibited the highest diversity, followed by the olfactory organ, gills, and gut. Flectobacillus was highly represented within skin and gill communities. Principal coordinate analysis and plots revealed clustering of external sites apart from internal sites. A highly diverse community was present within the epithelium, as demonstrated by confocal microscopy and pyrosequencing. Using in vitro assays, we demonstrated that two Arthrobacter sp. skin isolates, a Psychrobacter sp. strain, and a combined skin aerobic bacterial sample inhibit the growth of Saprolegnia australis and Mucor hiemalis, two important aquatic fungal pathogens. These results underscore the importance of symbiotic bacterial communities of fish and their potential role for the control of aquatic fungal diseases.


Assuntos
Antibiose , Arthrobacter/fisiologia , Microbiota , Mucor/crescimento & desenvolvimento , Oncorhynchus mykiss/microbiologia , Saprolegnia/crescimento & desenvolvimento , Pele/imunologia , Pele/microbiologia , Animais , Arthrobacter/classificação , Arthrobacter/genética , Arthrobacter/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Doenças dos Peixes/microbiologia , Brânquias/microbiologia , Mucor/fisiologia , Saprolegnia/fisiologia
18.
J Biosci Bioeng ; 119(3): 267-74, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25266375

RESUMO

An exo-inulinase gene was cloned from Arthrobacter sp. MN8, a cold-adapted bacterium isolated from lead-zinc-rich soil. The gene was expressed in Escherichia coli BL21(DE3). The resultant 505-residue polypeptide (InuAMN8) showed the highest identity (81.1%) with the putative levanase from Arthrobacter phenanthrenivorans Sphe3 (ADX73279) and shared 57.8% identity with the exo-inulinase from Bacillus sp. snu-7 (AAK00768). The purified recombinant InuAMN8 (rInuAMN8) showed an apparently optimal activity at 35°C, and 75.3%, 39.4%, and 15.8% of its maximum activity at 20°C, 10°C, and 0°C, respectively. After pre-incubation for 60 min at 50°C and 55°C, the rInuAMN8 exhibited 69.8% and 17.7% of its initial activity, respectively. The apparent Km values of rInuAMN8 towards inulin were 2.8, 1.5, 1.2, 5.3, and 8.2 mM at 0°C, 10°C, 20°C, 30°C, and 35°C, respectively. Inulin and Jerusalem artichoke tubers were effectively hydrolyzed to release fructose by rInuAMN8 at 0°C, 10°C, and 35°C. Compared with its hyperthermophilic and thermophilic counterparts, the exo-inulinase had less aromatic amino acid F and more hydrophobic amino acid A. In addition, the purified rInuAMN8 retained 127.9%-88.4% inulinase activity at 3.5%-15.0% (w/v) NaCl concentrations. Zn(2+) and Pb(2+) at 10 mM exhibited little or no effect on the enzyme activity. This paper is the first to report a cold-active and/or NaCl-tolerant exo-inulinase from the genus Arthrobacter. The exo-inulinase rInuAMN8 shows a potential for use in the production of fructose at low temperatures.


Assuntos
Aclimatação , Arthrobacter/enzimologia , Temperatura Baixa , Frutose/biossíntese , Glicosídeo Hidrolases/metabolismo , Cloreto de Sódio/farmacologia , Sequência de Aminoácidos , Arthrobacter/classificação , Arthrobacter/fisiologia , Bacillus/enzimologia , Clonagem Molecular , Escherichia coli/genética , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Hidrólise , Inulina/metabolismo , Dados de Sequência Molecular
19.
Plant Biol (Stuttg) ; 17(1): 288-93, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24750405

RESUMO

Salt-tolerant plant growth-promoting rhizobacteria (ST-PGPR) significantly influence the growth and yield of wheat crops in saline soil. Wheat growth improved in pots with inoculation of all nine ST-PGPR (ECe = 4.3 dS·m(-1) ; greenhouse experiment), while maximum growth and dry biomass was observed in isolate SU18 Arthrobacter sp.; simultaneously, all ST-PGPR improved soil health in treated pot soil over controls. In the field experiment, maximum wheat root dry weight and shoot biomass was observed after inoculation with SU44 B. aquimaris, and SU8 B. aquimaris, respectively, after 60 and 90 days. Isolate SU8 B. aquimaris, induced significantly higher proline and total soluble sugar accumulation in wheat, while isolate SU44 B. aquimaris, resulted in higher accumulation of reducing sugars after 60 days. Percentage nitrogen (N), potassium (K) and phosphorus (P) in leaves of wheat increased significantly after inoculation with ST-PGPR, as compared to un-inoculated plants. Isolate SU47 B. subtilis showed maximum reduction of sodium (Na) content in wheat leaves of about 23% at both 60 and 90 days after sowing, and produced the best yield of around 17.8% more than the control.


Assuntos
Rhizobium/fisiologia , Cloreto de Sódio/farmacologia , Triticum/microbiologia , Arthrobacter/fisiologia , Biomassa , Nitrogênio/metabolismo , Fósforo/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Folhas de Planta/fisiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Potássio/metabolismo , Salinidade , Plantas Tolerantes a Sal , Solo/química , Triticum/efeitos dos fármacos , Triticum/fisiologia
20.
Arch Microbiol ; 196(12): 863-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25150449

RESUMO

A Gram-staining-positive, catalase-positive, oxidase-negative, non-motile, non-flagellate and rod-shaped bacterium, was designated as DCY81(T), and isolated from soil of a ginseng field in Pocheon province, Republic of Korea. The 16S rRNA gene sequence analysis revealed that strain DCY81(T) belonged to the genus Arthrobacter. Major fatty acid was anteiso-C15:0, while major polar lipids were diphosphatidyglycerol, phatidyglycerol, phosphatidylinositol, monogalactosyldiacylglycerol (GL1), and dimannosyldiacylglycerol (GL2). The dominant quinone was MK-9(H2). The peptidoglycan type was A3α with an L-Lys-L-Ala-L-Thr-L-Ala interpeptide bridge. The DNA-DNA hybridization relatedness between strain DCY81(T) and Arthrobacter siccitolerans LMG 27359(T) (98.2 %), Arthrobacter sulfonivorans JCM 13520(T) (97.81 %), Arthrobacter scleromae DSM 17756(T) (97.59 %), Arthrobacter oxydans KCTC 3383(T) (97.3 %) was 39.1 ± 0.2, 62.2 ± 1.6, 36.8 ± 1.1 and 48.3 ± 1.6 %, respectively which show that the genotypic separation of strain DCY81(T) from the closest reference strain of the genus Arthrobacter. The DNA G+C content was 65.2 mol%. The genotypic analysis, physiological, and chemotaxonomic results indicate that strain DCY81(T) represents a novel species of the genus Arthrobacter. Therefore, Arthrobacter ginsengisoli sp. nov., is proposed as the type strain (=KCTC 29225(T) = JCM 19357(T)).


Assuntos
Arthrobacter/isolamento & purificação , Panax , Microbiologia do Solo , Arthrobacter/classificação , Arthrobacter/genética , Arthrobacter/fisiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Genes de RNAr , Lipídeos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/química , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
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