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1.
Artigo em Inglês | MEDLINE | ID: mdl-35133261

RESUMO

Three Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile strains (C130915_07T, C150915_16 and C150915_17) were isolated from lymph nodes of Algerian cows. On the basis of 16S rRNA gene and whole genome similarities, the isolates were almost identical and clearly grouped in the genus Pseudochrobactrum. This allocation was confirmed by the analysis of fatty acids (C19:cyclo, C18 : 1, C18 : 0, C16 : 1 and C16 : 0) and of polar lipids (major components: phosphatidylethanolamine, ornithine-lipids, phosphatidylglycerol, cardiolipin and phosphatidylcholine, plus moderate amounts of phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine and other aminolipids). Genomic, physiological and biochemical data differentiated these isolates from previously described Pseudochrobactrum species in DNA relatedness, carbon assimilation pattern and growth temperature range. Thus, these organisms represent a novel species of the genus Pseudochrobactrum, for which the name Pseudochrobactrum algeriensis sp. nov. is proposed (type strain C130915_07T=CECT30232T=LMG 32378T).


Assuntos
Brucellaceae/classificação , Bovinos/microbiologia , Linfonodos , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Brucellaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Linfonodos/microbiologia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
2.
Ecotoxicol Environ Saf ; 217: 112244, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933891

RESUMO

Nickel is widely spread by different anthropogenic activities and shows toxicity for plant growth and development. Whether rhizobia symbiotically fix nitrogen can eliminate or reduce nickel toxic effect on plant or not is still unknown. This study was aimed to investigate the effect of different rhizobia genus inoculation on growth, nitrogen fixing ability, metal accumulation and enzymatic antioxidative balance of Pongamia pinnnaa. Inoculation with Rhizobium pisi and Ochrobacterium pseudogrignonense increased the all the growth parameters both in 0 and 40 mg/kg nickel as comparison with control. Only shoot length increased in presence of nitrogen as compared with no supply of nitrogen. Nitrogen content also increased both in rhizobia inoculation as compared to no nitrogen supply and non-inoculation control, respectively. Nickel uptake was higher in shoots and leaves but lower in roots in case of inoculation as compared to non-inoculation control. Rhizobia inoculation improved the plant antioxidant capacity by increasing the activity of enzymatic scavengers catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and ascorbate (GR). However, 40 mg/kg of nickel adding showed mostly effect on the activity CAT, SOD, POD in leaves. All the enzymatic activity showed a significant increase in absence of nitrogen supply as compared nitrogen supply. Our results suggested that rhizobia inoculation effectively mediated nickel stress for legume plants by increasing nitrogen supplement and inducing antioxidant capacity.


Assuntos
Brucellaceae/fisiologia , Millettia/fisiologia , Níquel/metabolismo , Rhizobium/fisiologia , Antioxidantes , Ácido Ascórbico , Catalase/metabolismo , Millettia/metabolismo , Nitrogênio , Oxirredução , Raízes de Plantas/metabolismo , Superóxido Dismutase/metabolismo , Simbiose
3.
Int Microbiol ; 23(2): 189-200, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31297626

RESUMO

Black chicken feathers generated in large amount from poultry and slaughter houses are highly recalcitrant to microbial degradation due to their tough structural nature. A novel keratinolytic bacterium that possessed high affinity for black feather was isolated from chicken manure and identified as Pseudochrobactrum sp. IY-BUK1. Keratinase and feather soluble protein were effectively produced by the free living cells of the bacterium in media containing only black feathers and a mixture of equal amount of black-, brown- and white-coloured feathers. Complete degradation of 5 g/L of black feathers was completed in 3 days following optimisation of physico-chemical conditions. However, the bacterium selectively completed the degradation of black feather in a medium containing mixture of feathers in 144 h leaving behind approximately 33% and 45% of brown and white feathers in the medium respectively. Gellan gum-immobilised cells of strain IY-BUK1 enhanced the keratinase production by about 150% and were used repeatedly for ten cycles to degrade 5 g/L of black feather in a semi continuous fermentation of 18 h per cycle with enhanced and stable production of soluble protein. The study demonstrated the potential use of Pseudochrobactrum sp. IY-BUK1 not only in biodegradation of highly recalcitrant black feathers, but also in producing keratinase enzymes and valuable soluble proteins for possible industrial usage.


Assuntos
Biodegradação Ambiental , Brucellaceae/isolamento & purificação , Plumas/metabolismo , Hidrolisados de Proteína/biossíntese , Animais , Brucellaceae/metabolismo , Galinhas , Fezes/microbiologia , Peptídeo Hidrolases/biossíntese , Polissacarídeos Bacterianos/metabolismo
4.
Ecotoxicol Environ Saf ; 184: 109636, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31536849

RESUMO

Bioremediation of chromium (Cr(Ⅵ)) contaminations has been widely reported, but the research on its removal mechanism is still scarce. Studies on Cr(Ⅵ) removal by strains affiliated to genus Pseudochobactrum revealed the Cr(Ⅵ) efficiency removal through the reduction of Cr(Ⅵ) to Cr(Ⅲ). However, the location of Cr(Ⅵ) reduction reaction and exact mechanism are still unspecified. In this work, a Gram-positive bacterial strain, Pseudochrobactrum saccharolyticum W1 (P. saccharolyticum W1) was isolated and tested to remove approximately 53.7% of Cr(Ⅵ) (initial concentration was 200 mg L-1) from the MSM medium. Analysis of SEM-EDS and TEM-EDS indicated that chromium-containing particles precipitated both on the cell surface and in the cytoplasm. Batch experiments indicated that the heat-treated bacterial cells almost had no ability to remove Cr(Ⅵ) from solution, while the resting cells could remove 62.0% of Cr(Ⅵ) at the initial concentration of 10 mg L-1. Additionally, at this concentration, 64.8% and 70.8% of Cr(Ⅵ) was reduced by cell envelope components and intracellular soluble substances after 6 h, respectively. These results suggested that the removal of Cr(Ⅵ) by P. saccharolyticum W1 was through direct reduction, which occurred on both cell envelop and cytoplasm. The results also showed that cytoplasm was the main site for Cr(Ⅵ) reduction compared to the cell envelop. Further analysis of FTIR and XPS verified that C-H, C-C, CO, C-OH and C-O-C groups of cells involved in correlation with chromium during Cr(Ⅵ) reduction. The study offered an insight into the Cr(VI) reduction mechanism of P. saccharolyticum W1.


Assuntos
Brucellaceae/metabolismo , Cromo/análise , Modelos Teóricos , Biodegradação Ambiental , Brucellaceae/ultraestrutura , Membrana Celular/metabolismo , Cromo/metabolismo , Citoplasma/metabolismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução
5.
Int J Syst Evol Microbiol ; 69(3): 778-782, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30652966

RESUMO

A non-spore-forming, motile, Gram-stain-negative, short rod-shaped strain, designated HN4T, was isolated from a paddy soil sample collected in Shanghai, China. A comparative analysis o-f 16S rRNA gene sequences showed that strain HN4T fell within the genus Falsochrobactrum, forming a clear cluster with the type strain of Falsochrobactrum ovis, with which it exhibited a 16S rRNA gene sequence similarity value of 98.2 %. Strain HN4T grew optimally at pH 7.0, 30-35 °C and in the presence of 1 % (w/v) NaCl. It was positive for oxidase activity. Chemotaxonomic analysis showed that strain HN4T contained ubiquinone-10 as the predominant respiratory quinone and possessed summed feature 8(C18 : 1ω7c and/or C18 : 1ω6c) and C19 : 0cyclo ω8c as predominant fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G+C content was 56.9 mol%. Strain HN4T exhibited a DNA-DNA relatedness level of 18±1 % with Falsochrobactrum ovis CCM 8460T. Based on the data obtained in this study, strain HN4T represents a novel species of the genus Falsochrobactrum, for which the name Falsochrobactrumshanghaiense sp. nov. is proposed. The type strain is HN4T (=JCM 32785T=CCTCC AB 2018063T).


Assuntos
Brucellaceae/classificação , Oryza/microbiologia , Filogenia , Microbiologia do Solo , Ubiquinona/química , Técnicas de Tipagem Bacteriana , Composição de Bases , Brucellaceae/isolamento & purificação , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
J Hazard Mater ; 351: 240-249, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29550558

RESUMO

Although bioaugmentation of pollutant-contaminated sites is a great concern, there are few reports on the relationships among indigenous microbial consortia, exogenous inocula, and pollutants in a bioaugmentation process. In this study, bioaugmentation with Pseudochrobactrum sp. BSQ1 and Massilia sp. BLM18, which can hydrolytically and reductively dehalogenate chlorothalonil (TPN), respectively, was studied for its ability to remove TPN from soil; the alteration of the soil microbial community during the bioaugmentation process was investigated. The results showed that TPN (50 mg/kg) was completely removed in both bioaugmentation treatments within 35 days with half-lives of 6.8 and 9.8 days for strains BSQ1 and BLM18 respectively. In high concentration of TPN-treated soils (100 mg/kg), the bioaugmentation with strains BSQ1 and BLM18 respectively reduced 76.7% and 62.0% of TPN within 35 days. The TPN treatment significantly decreased bacterial richness and diversity and improved the growth of bacteria related to the elimination of chlorinated organic pollutants. However, little influence on soil microbial community was observed for each inoculation treatment (without TPN treatment), showing that TPN treatment is the main force for the shift in indigenous consortia. This study provides insights into the effects of halogenated fungicide application and bioaugmentation on indigenous soil microbiomes.


Assuntos
Brucellaceae/metabolismo , Fungicidas Industriais/metabolismo , Nitrilas/metabolismo , Oxalobacteraceae/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Hidrólise , Oxirredução
7.
PLoS One ; 12(5): e0178213, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542471

RESUMO

A stable bacterial consortium (LV-1) capable of degrading di-n-butyl phthalate (DBP) was enriched from river sludge. Community analysis revealed that the main families of LV-1 are Brucellaceae (62.78%) and Sinobacteraceae (14.83%), and the main genera of LV-1 are Brucella spp. (62.78%) and Sinobacter spp. (14.83%). The optimal pH and temperature for LV-1 to degrade DBP were pH 6.0 and 30°C, respectively. Inoculum size influenced the degradation ratio when the incubation time was < 24 h. The initial concentration of DBP also influenced the degradation rates of DBP by LV-1, and the degradation rates ranged from 69.0-775.0 mg/l/d in the first 24 h. Degradation of DBP was best fitted by first-order kinetics when the initial concentration was < 300 mg/l. In addition, Cd2+, Cr6+, and Zn2+ inhibited DBP degradation by LV-1 at all considered concentrations, but low concentrations of Pb2+, Cu2+, and Mn2+ enhanced DBP degradation. The main intermediates (mono-ethyl phthalate [MEP], mono-butyl phthalate [MBP], and phthalic acid [PA]) were identified in the DBP degradation process, thus a new biochemical pathway of DBP degradation is proposed. Furthermore, LV-1 also degraded other phthalates with shorter ester chains (DMP, DEP, and PA).


Assuntos
Biodegradação Ambiental , Dibutilftalato/metabolismo , Poluentes Ambientais/metabolismo , Esgotos/química , Brucellaceae/metabolismo , Sedimentos Geológicos/microbiologia , Esgotos/microbiologia , Microbiologia do Solo
8.
Sci Rep ; 7: 44420, 2017 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28300153

RESUMO

Twenty-one small Gram-negative motile coccobacilli were isolated from 15 systemically diseased African bullfrogs (Pyxicephalus edulis), and were initially identified as Ochrobactrum anthropi by standard microbiological identification systems. Phylogenetic reconstructions using combined molecular analyses and comparative whole genome analysis of the most diverse of the bullfrog strains verified affiliation with the genus Brucella and placed the isolates in a cluster containing B. inopinata and the other non-classical Brucella species but also revealed significant genetic differences within the group. Four representative but molecularly and phenotypically diverse strains were used for in vitro and in vivo infection experiments. All readily multiplied in macrophage-like murine J774-cells, and their overall intramacrophagic growth rate was comparable to that of B. inopinata BO1 and slightly higher than that of B. microti CCM 4915. In the BALB/c murine model of infection these strains replicated in both spleen and liver, but were less efficient than B. suis 1330. Some strains survived in the mammalian host for up to 12 weeks. The heterogeneity of these novel strains hampers a single species description but their phenotypic and genetic features suggest that they represent an evolutionary link between a soil-associated ancestor and the mammalian host-adapted pathogenic Brucella species.


Assuntos
Proteínas de Bactérias/genética , Brucellaceae/genética , Regulação Bacteriana da Expressão Gênica , Infecções por Bactérias Gram-Negativas/veterinária , Interações Hospedeiro-Patógeno , Filogenia , Animais , Animais de Zoológico , Anuros , Proteínas de Bactérias/metabolismo , Evolução Biológica , Brucellaceae/classificação , Brucellaceae/crescimento & desenvolvimento , Brucellaceae/metabolismo , Linhagem Celular , Flagelos/genética , Flagelos/metabolismo , Flagelos/ultraestrutura , Heterogeneidade Genética , Alemanha , Infecções por Bactérias Gram-Negativas/microbiologia , Fígado/microbiologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Tipagem de Sequências Multilocus , Baço/microbiologia , Tanzânia
9.
Biochemistry ; 54(30): 4692-703, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26200446

RESUMO

Polyamines are essential aliphatic polycations that bind to nucleic acids and accordingly are involved in a variety of cellular processes. Polyamine function can be regulated by acetylation and deacetylation, just as histone function can be regulated by lysine acetylation and deacetylation. Acetylpolyamine amidohydrolase (APAH) from Mycoplana ramosa is a zinc-dependent polyamine deacetylase that shares approximately 20% amino acid sequence identity with human histone deacetylases. We now report the X-ray crystal structures of APAH-inhibitor complexes in a new and superior crystal form that diffracts to very high resolution (1.1-1.4 Å). Inhibitors include previously synthesized analogues of N(8)-acetylspermidine bearing trifluoromethylketone, thiol, and hydroxamate zinc-binding groups [Decroos, C., Bowman, C. M., and Christianson, D. W. (2013) Bioorg. Med. Chem. 21, 4530], and newly synthesized hydroxamate analogues of shorter, monoacetylated diamines, the most potent of which is the hydroxamate analogue of N-acetylcadaverine (IC50 = 68 nM). The high-resolution crystal structures of APAH-inhibitor complexes provide key inferences about the inhibition and catalytic mechanism of zinc-dependent deacetylases. For example, the trifluoromethylketone analogue of N(8)-acetylspermidine binds as a tetrahedral gem-diol that mimics the tetrahedral intermediate and its flanking transition states in catalysis. Surprisingly, this compound is also a potent inhibitor of human histone deacetylase 8 with an IC50 of 260 nM. Crystal structures of APAH-inhibitor complexes are determined at the highest resolution of any currently existing zinc deacetylase structure and thus represent the most accurate reference points for understanding structure-mechanism and structure-inhibition relationships in this critically important enzyme family.


Assuntos
Aminoidrolases/química , Proteínas de Bactérias/química , Brucellaceae/enzimologia , Inibidores Enzimáticos/química , Zinco/química , Aminoidrolases/antagonistas & inibidores , Proteínas de Bactérias/antagonistas & inibidores , Cristalografia por Raios X , Humanos , Estrutura Terciária de Proteína
10.
Am J Physiol Lung Cell Mol Physiol ; 309(1): L76-83, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25957290

RESUMO

Acute lung injury (ALI) and the more severe acute respiratory distress syndrome are common responses to a variety of infectious and noninfectious insults. We used a mouse model of ALI induced by intratracheal administration of sterile bacterial wall lipopolysaccharide (LPS) to investigate the changes in innate lung microbiota and study microbial community reaction to lung inflammation and barrier dysfunction induced by endotoxin insult. One group of C57BL/6J mice received LPS via intratracheal injection (n = 6), and another received sterile water (n = 7). Bronchoalveolar lavage (BAL) was performed at 72 h after treatment. Bacterial DNA was extracted and used for qPCR and 16S rRNA gene-tag (V3-V4) sequencing (Illumina). The bacterial load in BAL from ALI mice was increased fivefold (P = 0.03). The community complexity remained unchanged (Simpson index, P = 0.7); the Shannon diversity index indicated the increase of community evenness in response to ALI (P = 0.07). Principal coordinate analysis and analysis of similarity (ANOSIM) test (P = 0.005) revealed a significant difference between microbiota of control and ALI groups. Bacteria from families Xanthomonadaceae and Brucellaceae increased their abundance in the ALI group as determined by Metastats test (P < 0.02). In concordance with the 16s-tag data, Stenotrohomonas maltophilia (Xanthomonadaceae) and Ochrobactrum anthropi (Brucellaceae) were isolated from lungs of mice from both groups. Metabolic profiling of BAL detected the presence of bacterial substrates suitable for both isolates. Additionally, microbiota from LPS-treated mice intensified IL-6-induced lung inflammation in naive mice. We conclude that the morbid transformation of ALI microbiota was attributed to the set of inborn opportunistic pathogens thriving in the environment of inflamed lung, rather than the external infectious agents.


Assuntos
Lesão Pulmonar/microbiologia , Pulmão/microbiologia , Microbiota/efeitos dos fármacos , Síndrome do Desconforto Respiratório/microbiologia , Animais , Sequência de Bases , Líquido da Lavagem Broncoalveolar/microbiologia , Brucellaceae/genética , Brucellaceae/isolamento & purificação , DNA Bacteriano/genética , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Xanthomonadaceae/genética , Xanthomonadaceae/isolamento & purificação
11.
Int J Mol Sci ; 16(4): 7320-33, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25837630

RESUMO

The phenol-degrading efficiency of Pseudochrobactrum sp. was enhanced by ultraviolet (UV) irradiation. First, a bacterial strain, Pseudochrobactrum sp. XF1, was isolated from the activated sludge in a coking plant. It was subjected to mutation by UV radiation for 120 s and a mutant strain with higher phenol-degrading efficiency, Pseudochrobactrum sp. XF1-UV, was selected. The mutant strain XF1-UV was capable of degrading 1800 mg/L phenol completely within 48 h and had higher tolerance to hydrogen ion concentration and temperature variation than the wild type. Haldane's kinetic model was used to fit the exponential growth data and the following kinetic parameters were obtained: µmax = 0.092 h-1, Ks = 22.517 mg/L, and Ki = 1126.725 mg/L for XF1, whereas µmax = 0.110 h-1, Ks = 23.934 mg/L, and Ki = 1579.134 mg/L for XF1-UV. Both XF1 and XF1-UV degraded phenol through the ortho-pathway; but the phenol hydroxylase activity of XF1-UV1 was higher than that of XF1, therefore, the mutant strain biodegraded phenol faster. Taken together, our results suggest that Pseudochrobactrum sp. XF1-UV could be a promising candidate for bioremediation of phenol-containing wastewaters.


Assuntos
Brucellaceae/genética , Brucellaceae/metabolismo , Mutação/genética , Fenol/metabolismo , Esgotos/microbiologia , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Temperatura , Raios Ultravioleta , Águas Residuárias/microbiologia
12.
Int J Syst Evol Microbiol ; 64(Pt 5): 1724-1728, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554640

RESUMO

A Gram-stain-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (strain 280(T)) isolated from a chicken was studied for its taxonomic allocation. 16S rRNA gene sequence analyses clearly allocated the isolate in the genus Paenochrobactrum group with a 16S rRNA gene sequence similarity of 98.8% to the currently recognized species, Paenochrobactrum gallinarii and Paenochrobactrum glaciei. This allocation was confirmed by the fatty acid data (major fatty acids: C18:1ω7c and C19:0 cyclo ω8c) and a polyamine pattern with the major compound putrescine and relatively high amounts of spermidine. Also, the polar lipid profile with phosphatidylethanolamine, phosphatiylmonomethylethanolamine, phosphatidylglycerol, phosphatidylcholine and the genus-specific 'stretched aminolipid' was well in line with the description of the genus Paenochrobactrum. The quinone system consisted predominantly of ubiquinone Q-10 with traces of Q-9 and Q-11. DNA-DNA hybridization of strain 280T with Paenochrobactrum gallinarii Sa25T and Paenochrobactrum glaciei KMM 3858T showed relatedness values of 38.8% (reciprocal 20.2%) and 30.2% (reciprocal 29.8%), respectively. These results in combination with differentiating physiological and biochemical data clearly showed that strain 280T merits species status. We propose the name Paenochrobactrum pullorum sp. nov. to accommodate this strain with the type strain 280T (=LMG 28095T=CIP 110700T).


Assuntos
Brucellaceae/classificação , Galinhas/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Brucellaceae/genética , Brucellaceae/isolamento & purificação , Galinhas/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Alemanha , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Putrescina/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/química , Ubiquinona/química
13.
J Bacteriol ; 196(5): 920-30, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24336939

RESUMO

Brucella species include important zoonotic pathogens that have a substantial impact on both agriculture and human health throughout the world. Brucellae are thought of as "stealth pathogens" that escape recognition by the host innate immune response, modulate the acquired immune response, and evade intracellular destruction. We analyzed the genome sequences of members of the family Brucellaceae to assess its evolutionary history from likely free-living soil-based progenitors into highly successful intracellular pathogens. Phylogenetic analysis split the genus into two groups: recently identified and early-dividing "atypical" strains and a highly conserved "classical" core clade containing the major pathogenic species. Lateral gene transfer events brought unique genomic regions into Brucella that differentiated them from Ochrobactrum and allowed the stepwise acquisition of virulence factors that include a type IV secretion system, a perosamine-based O antigen, and systems for sequestering metal ions that are absent in progenitors. Subsequent radiation within the core Brucella resulted in lineages that appear to have evolved within their preferred mammalian hosts, restricting their virulence to become stealth pathogens capable of causing long-term chronic infections.


Assuntos
Evolução Biológica , Brucellaceae/genética , Brucellaceae/patogenicidade , Genoma Bacteriano , Genômica/métodos , Filogenia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Virulência
14.
Environ Sci Pollut Res Int ; 21(4): 2592-602, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24091525

RESUMO

This study investigated the effectiveness of successive bioaugmentation, conventional bioaugmentation, and biostimulation of biodegradation of B10 in soil. In addition, the structure of the soil microbial community was assessed by polymerase chain reaction-denaturing gradient gel electrophoresis. The consortium was inoculated on the initial and the 11th day of incubation for successive bioaugmentation and only on the initial day for bioaugmentation and conventional bioaugmentation. The experiment was conducted for 32 days. The microbial consortium was identified based on sequencing of 16S rRNA gene and consisted as Pseudomonas aeruginosa, Achromobacter xylosoxidans, and Ochrobactrum intermedium. Nutrient introduction (biostimulation) promoted a positive effect on microbial populations. The results indicate that the edaphic community structure and dynamics were different according to the treatments employed. CO2 evolution demonstrated no significant difference in soil microbial activity between biostimulation and bioaugmentation treatments. The total petroleum hydrocarbon (TPH) analysis indicated a biodegradation level of 35.7 and 32.2 % for the biostimulation and successive bioaugmentation treatments, respectively. Successive bioaugmentation displayed positive effects on biodegradation, with a substantial reduction in TPH levels.


Assuntos
Achromobacter denitrificans/fisiologia , Biocombustíveis , Brucellaceae/fisiologia , Gasolina , Hidrocarbonetos/metabolismo , Pseudomonas aeruginosa/fisiologia , Poluentes do Solo/metabolismo , Achromobacter denitrificans/isolamento & purificação , Biodegradação Ambiental , Brucellaceae/isolamento & purificação , Dióxido de Carbono/metabolismo , DNA Bacteriano/genética , Eletroforese em Gel de Gradiente Desnaturante , Consórcios Microbianos/fisiologia , Reação em Cadeia da Polimerase , Pseudomonas aeruginosa/isolamento & purificação , RNA Ribossômico 16S/genética , Microbiologia do Solo
15.
J Microbiol Biotechnol ; 23(8): 1123-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23727810

RESUMO

The removal of toxic Cr(VI) by microorganisms is a promising approach for Cr(VI) pollution remediation. In the present study, four indigenous bacteria, named LY1, LY2, LY6, and LY7, were isolated from Cr(VI)-contaminated soil. Among the four Cr(VI)-resistant isolates, strain LY6 displayed the highest Cr(VI)-removing ability, with 100 mg/l Cr(VI) being completely removed within 144 h. It could effectively remove Cr(VI) over a wide pH range from 5.5 to 9.5, with the optimal pH of 8.5. The amount of Cr(VI) removed increased with initial Cr(VI) concentration. Data from the time-course analysis of Cr(VI) removal by strain LY6 followed first-order kinetics. Based on the 16S rRNA gene sequence, strain LY6 was identified as Pseudochrobactrum asaccharolyticum, a species that had never been reported for Cr(VI) removal before. Transmission electron microscopy and energy dispersive X-ray spectroscopy analysis further confirmed that strain LY6 could accumulate chromium within the cell while conducting Cr(VI) removal. The results suggested that the indigenous bacterial strain LY6 would be a new candidate for potential application in Cr(VI) pollution bioremediation.


Assuntos
Brucellaceae/metabolismo , Cromo/metabolismo , Cromo/toxicidade , Farmacorresistência Bacteriana , Microbiologia do Solo , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Brucellaceae/classificação , Brucellaceae/genética , Brucellaceae/isolamento & purificação , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria por Raios X
16.
J Environ Manage ; 126: 7-12, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23644665

RESUMO

Two marine bacterial strains, B5 and H24, were isolated from long-term Cr(VI) contaminated seawater and identified as Pseudochrobactrum and Proteus, respectively, based on 16S rRNA gene sequence analyses. Both strains were examined for their tolerance to Cr(VI) and other metal salts and their abilities to reduce Cr(VI) to trivalent chromium [Cr(III)]. Growing cells of Pseudochrobactrum sp. B5 and Proteus sp. H24 could tolerate Cr(VI) at a concentration of 2000 and 1500 mg/l and completely reduce 1000 mg/l Cr(VI) in LB medium within 96 and 144 h, respectively. Resting cells of the two strains were able to reduce 200mg/l Cr(VI) in Tris-HCl buffer within 16 and 24h, respectively. Furthermore, resting cells of both strains were able to reduce Cr(VI) in industrial wastewaters three times consecutively. Overall, this study provides evidence of the potential for application of chromate-reducing bacteria to direct Cr(VI) decontamination of industrial effluents.


Assuntos
Brucellaceae/metabolismo , Cromatos/isolamento & purificação , Cromatos/metabolismo , Proteus/metabolismo , Águas Residuárias/microbiologia , Biodegradação Ambiental , Brucellaceae/efeitos dos fármacos , Brucellaceae/genética , Cromatos/farmacologia , Concentração de Íons de Hidrogênio , Resíduos Industriais , Dados de Sequência Molecular , Oxirredução , Proteus/efeitos dos fármacos , Proteus/genética , RNA Ribossômico 16S , Água do Mar/microbiologia , Temperatura , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo
17.
J Hazard Mater ; 256-257: 24-32, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23669787

RESUMO

A novel Cr(VI)-reducing strain, Pseudochrobactrum saccharolyticum LY10, was isolated and characterized for its high Cr(VI)-reducing ability. Strain LY10 had typical characteristics of alkali-tolerance and halotolerance. Kinetic analysis indicated that the maximum reduction rate was achieved under optimum conditions with initial pH 8.3, 20gL(-1) NaCl, 55mgL(-1) Cr(VI), and 1.47×10(9)cellsmL(-1) of cell concentration. Further mechanism studies verified that the removal of Cr(VI) was mainly achieved by a metabolism-dependent bioreduction process. Strain LY10 accumulated chromium both in and around the cells, with cell walls acting as the major binding sites for chromium. X-ray absorption near-edge structure (XANES) analysis further confirmed that the chromium immobilized by the cells was in the Cr(III) state. In the present study, Pseudochrobactrum saccharolyticum was, for the first time, reported to be a Cr(VI)-reducing bacteria. Results from this research would provide a potential candidate for bioremediation of Cr(VI)-contaminated environments, especially alkaline and saline milieus with Cr(VI) at low-to-mid concentrations.


Assuntos
Brucellaceae/metabolismo , Cromo/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Brucellaceae/ultraestrutura , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Oxirredução , Salinidade
18.
Int J Syst Evol Microbiol ; 60(Pt 7): 1493-1498, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19684318

RESUMO

A Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (Sa25(T)) was isolated from air of a duck barn. 16S rRNA gene and recA sequence analyses clearly placed the isolate in the vicinity of the Brucella-Ochrobactrum-Pseudochrobactrum group, with the closest relative being Pseudochrobactrum glaciei KMM 3858(T). This allocation was confirmed by analyses of the quinone system (ubiquinone Q-10), fatty acid data (major fatty acids C(18 : 1)omega7c and C(19 : 0) cyclo omega8c) and polar lipid profile (major components diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and unknown aminolipid AL1; moderate amounts of three unknown polar lipids, L1-L3, an unknown aminolipid and an unknown aminophospholipid APL2). The polyamine pattern of Sa25(T) exhibited the major compound putrescine and moderate amounts of spermidine; a similar polyamine pattern with the major compound putrescine was also detected in Pseudochrobactrum glaciei KMM 3858(T). DNA-DNA hybridization of strain Sa25(T) with Pseudochrobactrum glaciei KMM 3858(T) and the type strains of the other Pseudochrobactrum species showed values ranging from 50.3 to 24.8 %, and physiological and biochemical data clearly differentiated this isolate from the described Pseudochrobactrum species. Since Sa25(T) and Pseudochrobactrum glaciei KMM 3858(T) form a distinct lineage in the 16S rRNA gene sequence-based phylogenetic tree, and this separate position is supported by unique characteristics of their polyamine patterns and polar lipid profiles, we propose the novel genus Paenochrobactrum gen. nov., with the type species Paenochrobactrum gallinarii sp. nov. (type strain Sa25(T) =CCUG 57736(T) =CCM 7656(T)) and the reclassification of Pseudochrobactrum glaciei as Paenochrobactrum glaciei comb. nov. (type strain Pi26(T) =KMM 3858(T) =NRIC 0733(T) =JCM 15115(T)).


Assuntos
Microbiologia do Ar , Brucellaceae/classificação , Agricultura , Animais , Sequência de Bases , Brucellaceae/genética , Brucellaceae/isolamento & purificação , Brucellaceae/fisiologia , Patos , Ácidos Graxos/análise , Dados de Sequência Molecular , Ochrobactrum/classificação , Filogenia , RNA Ribossômico 16S/genética
19.
Int J Syst Evol Microbiol ; 59(Pt 12): 3155-60, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19643873

RESUMO

A Gram-negative, motile and rod-shaped bacterial strain, BIO-TAS2-2(T), of the class Alphaproteobacteria, was isolated from a soil in Korea and studied using a polyphasic taxonomic approach. Strain BIO-TAS2-2(T) grew optimally at pH 7.5-8.5 and 30 degrees C and in the presence of 0-1.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain BIO-TAS2-2(T) fell within the clade comprising species of the genus Brevundimonas, forming a coherent cluster with Brevundimonas terrae KSL-145(T) and Brevundimonas diminuta LMG 2089(T). It exhibited 16S rRNA gene sequence similarity values of 96.0-98.7 % to members of the genus Brevundimonas and Mycoplana bullata IAM 13153(T). Strain BIO-TAS2-2(T) contained Q-10 as the predominant ubiquinone and cyclo-C(18 : 1)omega7c and C(16 : 0) as the major fatty acids. The DNA G+C content was 67.0 mol%. Strain BIO-TAS2-2(T) exhibited DNA-DNA relatedness levels of 12-19 % with the type strains of phylogenetically related Brevundimonas species and M. bullata. The novel strain could be differentiated from Brevundimonas species and M. bullata by differences in phenotypic characteristics. On the basis of phenotypic, phylogenetic and genetic data, strain BIO-TAS2-2(T) is considered to represent a novel species of the genus Brevundimonas, for which the name Brevundimonas naejangsanensis sp. nov. is proposed. The type strain is BIO-TAS2-2(T) (=KCTC 22631(T)=CCUG 57609(T)). In this study, it is also proposed that Mycoplana bullata be transferred to the genus Brevundimonas as Brevundimonas bullata comb. nov. (type strain TK0051(T)=ATCC 4278(T)=DSM 7126(T)=JCM 20846(T)=LMG 17157(T)).


Assuntos
Brucellaceae/classificação , Caulobacteraceae/classificação , Caulobacteraceae/isolamento & purificação , Brucellaceae/genética , Brucellaceae/isolamento & purificação , Brucellaceae/metabolismo , Caulobacteraceae/genética , Caulobacteraceae/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do Solo
20.
Int J Syst Evol Microbiol ; 59(Pt 10): 2464-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19622660

RESUMO

A Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (KSS 7.8(T)) was isolated from a water-mixed metal-working fluid. On the basis of 16S rRNA gene and recA sequence similarities, the isolate was clearly grouped in the genus Pseudochrobactrum. This allocation was confirmed by fatty acid data (major fatty acids: C(18 : 2)omega7c and C(19 : 0) cyclo omega8c), polar lipid profile (major components: phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine, plus moderate amounts of phosphatidylmonomethylethanolamine and unknown aminolipid AL1), quinone system (ubiquinone Q-10) and polyamine pattern (spermidine and putrescine predominant). DNA-DNA pairing with the most closely related Pseudochrobactrum species showed values ranging from 24.2 to 45.7 %, and physiological and biochemical data clearly differentiated this isolate from described Pseudochrobactrum species. This organism represents a novel species of the genus Pseudochrobactrum, for which the name Pseudochrobactrum lubricantis sp. nov. is proposed, with the type strain KSS 7.8(T) (=CCUG 56963(T)=CCM 7581(T)).


Assuntos
Brucellaceae/isolamento & purificação , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Brucellaceae/classificação , Brucellaceae/genética , Brucellaceae/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
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