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1.
J Basic Microbiol ; 61(8): 757-768, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34101885

RESUMO

The purpose of this study was to isolate lignin-degrading bacteria from buffalo rumen and to explore their interactions further. Using lignin as the carbon source, three bacteria, B-04 (Ochrobactrum pseudintermedium), B-11 (Klebsiella pneumoniae), and B-45 (Bacillus sonorensis), which have shown lignin degradation potential, were successfully isolated and identified from the rumen fluid of buffalo by colony morphology, 16S ribosomal RNA gene sequencing, and biochemical and physiological analyses. The degradation rates of lignin were determined, and the maximum values were 4.86%, 11.1%, and 7.68% for B-04, B-11, and B-45, respectively. The maximum laccase activities were 0.65, 0.93, and 1.15 U/ml, while the maximum lignin peroxidase activities were 5.72, 8.29, and 18.69 U/ml, respectively. Pairwise interaction studies showed inhibitory interaction between B-04 and B-45, inhibitory interaction between B-04 and B-11, and symbiotic interaction between B-11 and B-45. This is the first report on the lignin degradation ability of bacteria isolated from the buffalo's rumen, which provides a new understanding for revealing the mechanism of roughage tolerance of buffalo.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Búfalos/microbiologia , Lignina/metabolismo , Rúmen/microbiologia , Animais , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bactérias/classificação , Bactérias/genética , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/metabolismo , Interações Microbianas , Ochrobactrum/isolamento & purificação , Ochrobactrum/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Alinhamento de Sequência
2.
Ticks Tick Borne Dis ; 12(1): 101588, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33075731

RESUMO

Ticks are common vectors of human and animal diseases. Ochrobactrum spp. belong to the Brucellaceae family and have recently been recognized as emerging human pathogens. The ability of Haemaphysalis longicornis ticks to carry Ochrobactrum spp. remains uncertain. During June and July 2018, 686 ticks were collected from 11 sites in Pingdingshan Henan province in central China. We extracted 169 DNA samples for Brucellaceae 16S rRNA nested PCR and sequenced them in order to identify Ochrobactrum spp. The data sequences were aligned with NCBI BLAST program and phylogenetic tree was constructed using Mega 5.0. Twenty samples were sequenced successfully out of a total forty-one positive for Brucellaceae. Thirteen DNA samples were identical to O. intermedium (99.85 %-100.00 %) and 3 were identical to O. cicer (99.85 %-100.00 %) (15 collected from host and one from vegetation). Four DNA samples (3 collected from host and one from vegetation) had 99.83-100 % B. melitensis identity. This study adds to the growing body of evidence that shows Ochrobactrum spp. are present in H. longicornis. Ochrobactrum spp. and Brucella spp. are phenotypically and genetically closely related pathogens. Our finding highlights the importance of gene sequencing and phylogenetic analysis to differentiate between Ochrobactrum spp. and Brucella spp. in the research and potentially clinical setting. Future work is required to investigate the transmission potential of Ochrobactrum spp. by H. longicornis.


Assuntos
Brucella/isolamento & purificação , Ixodidae/microbiologia , Ochrobactrum/isolamento & purificação , Animais , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Filogenia , Reação em Cadeia da Polimerase , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
3.
Acta Diabetol ; 58(2): 191-195, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32940798

RESUMO

INTRODUCTION: The higher frequency of infections in diabetic patients is caused by a hyperglycemic environment, which promotes immune dysfunction. People with diabetes are more prone to skin infections. A continuous glucose monitoring (CGM) system provides information on changes in blood glucose (BG) levels throughout the day. Its use facilitates optimal therapeutic decisions for a diabetic patient. One of the factors limiting the use of CGM is inflammation at the insertion site. AIM OF THE STUDY: The aim of the study was the microbiological identification of the bacterial strains which are found on CGM sensor electrodes. MATERIAL AND METHODS: We performed microbiological tests on patients' CGM Enlite Medtronic electrodes, which were removed after 6 days of usage according to the manufacturer's instructions. 31 sensors were examined from 31 children (14 girls) aged from 0.5 to 14.6 years. The microbiological analysis was routinely performed at the Department of Children's Diabetology Medical University of Silesia in Katowice, Poland. RESULTS: 12 (39%) of the electrodes were colonized. In 11 (92%) cases the electrodes were colonized by one bacteria strain. 7 times methicillin-sensitive coagulase negative staphylococcus (MSCNS) was detected. We also found one case of Klebsiella pneumoniae, Ochrobactrum tritici, Bacillus sonorensis and methicillin-resistant coagulase-negative Staphylococci (MRCNS) colonization. One electrode was colonized by the mixed flora Enterococcus faecalis, methicillin-susceptible coagulase-negative Staphylococci (MSCNS), Pseudomonas stutzeri, methicillin-susceptible Staphylococcus aureus (MSSA). The median HbA1c in the group with colonization of electrodes was 6, 85% (6, 3-7, 6%) versus 6, 3% (5, 8-7, 5%) in the group without colonization. The median BMI in the group with colonization of the electrodes was 17.10 kg/m2 (16.28-18.62 kg/m2) versus 15.98 kg/m2 (15.14-17.96 kg/m2) in the group without colonization. Statistically, significantly more frequently electrodes are colonized in older children (median age in the group with colonization of electrodes 11.43 years (6.52-12.27 years), without colonization 8.42 years. (3.098-9.375 years); (p = 0.033). CONCLUSIONS: It seems that older children are more likely to have their sensor electrode colonized by bacterial strains.


Assuntos
Bactérias/isolamento & purificação , Glicemia/análise , Diabetes Mellitus Tipo 1/sangue , Contaminação de Equipamentos/estatística & dados numéricos , Equipamentos e Provisões/microbiologia , Adolescente , Bacillus/isolamento & purificação , Bactérias/classificação , Automonitorização da Glicemia/instrumentação , Automonitorização da Glicemia/estatística & dados numéricos , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/microbiologia , Eletrodos/efeitos adversos , Eletrodos/microbiologia , Eletrodos/estatística & dados numéricos , Equipamentos e Provisões/efeitos adversos , Equipamentos e Provisões/normas , Equipamentos e Provisões/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Ochrobactrum/isolamento & purificação , Polônia/epidemiologia , Dermatopatias Bacterianas/complicações , Dermatopatias Bacterianas/epidemiologia , Dermatopatias Bacterianas/microbiologia , Staphylococcus/isolamento & purificação
4.
Biomolecules ; 10(6)2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32580482

RESUMO

Manganese-oxidizing bacteria have been widely investigated for bioremediation of Mn-contaminated water sources and for production of biogenic Mn oxides that have extensive applications in environmental remediation. In this study, a total of 5 Mn-resistant bacteria were isolated from river water and investigated for Mn removal. Among them, Ochrobactrum sp. NDMn-6 exhibited the highest Mn removal efficiency (99.1%). The final precipitates produced by this strain were defined as a mixture of Mn2O3, MnO2, and MnCO3. Optimal Mn-removal performance by strain NDMn-6 was obtained at a temperature range of 25-30 °C and the salinity of 0.1-0.5%. More interestingly, strain NDMn-6 could be resistant to salinities of up to 5%, revealing that this strain could be possibly applied for Mn remediation of high salinity regions or industrial saline wastewaters. This study also revealed the potential of self-detoxification mechanisms, wherein river water contaminated with Mn could be cleaned by indigenous bacteria through an appropriate biostimulation scheme.


Assuntos
Compostos de Manganês/isolamento & purificação , Ochrobactrum/isolamento & purificação , Rios/química , Poluentes Químicos da Água/isolamento & purificação , Compostos de Manganês/química , Compostos de Manganês/metabolismo , Ochrobactrum/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
5.
Genomics ; 112(5): 3003-3012, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32428556

RESUMO

Ochrobactrum genus is comprised of soil-dwelling Gram-negative bacteria mainly reported for bioremediation of toxic compounds. Since last few years, mainly two species of this genus, O. intermedium and O. anthropi were documented for causing infections mostly in the immunocompromised patients. Despite such ubiquitous presence, study of adaptation in various niches is still lacking. Thus, to gain insights into the niche adaptation strategies, pan-genome analysis was carried out by comparing 67 genome sequences belonging to Ochrobactrum species. Pan-genome analysis revealed it is an open pan-genome indicative of the continuously evolving nature of the genus. The presence/absence of gene clusters also illustrated the unique presence of antibiotic efflux transporter genes and type IV secretion system genes in the clinical strains while the genes of solvent resistance and exporter pumps in the environmental strains. A phylogenomic investigation based on 75 core genes depicted better and robust phylogenetic resolution and topology than the 16S rRNA gene. To support the pan-genome analysis, individual genomes were also investigated for the mobile genetic elements (MGE), antibiotic resistance genes (ARG), metal resistance genes (MRG) and virulence factors (VF). The analysis revealed the presence of MGE, ARG, and MRG in all the strains which play an important role in the species evolution which is in agreement with the pan-genome analysis. The average nucleotide identity (ANI) based on the genetic relatedness between the Ochrobactrum species indicated a distinction between individual species. Interestingly, the ANI tool was able to classify the Ochrobactrum genomes to the species level which were assigned till the genus level on the NCBI database.


Assuntos
Genoma Bacteriano , Ochrobactrum/genética , Farmacorresistência Bacteriana/genética , Microbiologia Ambiental , Genes Bacterianos , Genômica , Humanos , Sequências Repetitivas Dispersas , Anotação de Sequência Molecular , Ochrobactrum/classificação , Ochrobactrum/isolamento & purificação , Ochrobactrum/patogenicidade , Filogenia , Fatores de Virulência
6.
Int J Syst Evol Microbiol ; 70(4): 2217-2225, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32100690

RESUMO

A Gram-stain-negative, non-spore-forming, motile, aerobic, rod-shaped bacteria strain, designated LCB8T, was isolated from the insect Teleogryllus occipitalis captured from a deserted cropland in Shuangliu district, Chengdu, PR China. Phylogenetic analysis on the basis of 16S rRNA gene sequence indicated that the strain represented a member of the genus Ochrobactrum, family Brucellaceae, class Alphaproteobacteria. Ochrobactrum pecoris CCUG 60088T (97.9 %) and Ochrobactrum haematophilum CCUG 38531T (98.8 %) were identified as the most closely related phylogenetic neighbours of strain LCB8T. The novel strain was able to grow at salt concentrations of 0-4.5 % (w/v), pH 5-9 and temperatures of 20-42 °C. The major quinone system was ubiquinone Q-10, the major fatty acids were C18 : 1ω7c, C16 : 0 and C18 : 0. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylmonomethylethanolamine, diphosphatidylglycerol and four undefined aminolipids. The major polyamines were putrescine and spermidine. Genome sequencing revealed a genome size of 4.76 Mbp and a DNA G+C content of 57.1 mol%. These phenotypic, genotypic and chemotaxonomic traits excellently supported the affiliation of LCB8T to the genus Ochrobactrum. Pairwise determined whole-genome average nucleotide identity (ANI) values indicated that strain LCB8T represents a novel species, for which we propose the name Ochrobactrum teleogrylli sp. nov. with the type strain LCB8T (=KCTC 72031T=CGMCC 1.13984T).


Assuntos
Gryllidae/microbiologia , Ochrobactrum/classificação , Filogenia , Agricultura , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Ochrobactrum/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
8.
Can J Microbiol ; 66(2): 144-160, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31714812

RESUMO

Growth and productivity of rice are negatively affected by soil salinity. However, some salt-tolerant rhizosphere-inhabiting bacteria can improve salt resistance of plants, thereby augmenting plant growth and production. Here, we isolated a total of 53 plant-growth-promoting rhizobacteria (PGPR) from saline and non-saline areas in Bangladesh where electrical conductivity was measured as >7.45 and <1.80 dS/m, respectively. Bacteria isolated from saline areas were able to grow in a salt concentration of up to 2.60 mol/L, contrary to the isolates collected from non-saline areas that did not survive beyond 854 mmol/L. Among the salt-tolerant isolates, Bacillus aryabhattai, Achromobacter denitrificans, and Ochrobactrum intermedium, identified by comparing respective sequences of 16S rRNA using the NCBI GenBank, exhibited a higher amount of atmospheric nitrogen fixation, phosphate solubilization, and indoleacetic acid production at 200 mmol/L salt stress. Salt-tolerant isolates exhibited greater resistance to heavy metals and antibiotics, which could be due to the production of an exopolysaccharide layer outside the cell surface. Oryza sativa L. fertilized with B. aryabhattai MS3 and grown under 200 mmol/L salt stress was found to be favoured by enhanced expression of a set of at least four salt-responsive plant genes: BZ8, SOS1, GIG, and NHX1. Fertilization of rice with osmoprotectant-producing PGPR, therefore, could be a climate-change-preparedness strategy for coastal agriculture.


Assuntos
Achromobacter denitrificans/fisiologia , Bacillus/fisiologia , Ácidos Indolacéticos/metabolismo , Ochrobactrum/fisiologia , Oryza/microbiologia , Achromobacter denitrificans/genética , Achromobacter denitrificans/isolamento & purificação , Bacillus/genética , Bacillus/isolamento & purificação , Bangladesh , Fixação de Nitrogênio , Ochrobactrum/genética , Ochrobactrum/isolamento & purificação , Oryza/fisiologia , Fosfatos/metabolismo , RNA Ribossômico 16S/genética , Rizosfera , Salinidade , Estresse Salino , Tolerância ao Sal , Solo/química , Microbiologia do Solo
9.
J Environ Sci Health B ; 54(6): 505-513, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30909840

RESUMO

A dominant strain named Ochrobactrum sp. was isolated from soils contaminated with coal tar. The batch experiments were carried out to study the co-metabolic degradation of pyrene by Ochrobactrum MB-2 with naphthalene as the main substrate and the effects of several significant parameters such as naphthalene concentration, pH and temperature on removal efficiency were explored. The results showed that Ochrobactrum MB-2 effectively degraded naphthalene and that the addition of naphthalene favored the degradation of pyrene. The maximum elimination efficiency of naphthalene (10 mg L-1) and pyrene (1 mg L-1) was achieved at pH 7 and 25 °C, and the corresponding values were 99 and 41%, respectively. A competitive inhibition model based on the Michaelis-Menten equation was used to characterize the inhibitory effect of pyrene on naphthalene degradation. The values of the half-saturation coefficient for naphthalene (KS) and dissociation constant of enzyme-inhibitor complex (KC) were determined to be 4.93 and 1.38 mg L-1, respectively.


Assuntos
Naftalenos/metabolismo , Ochrobactrum/metabolismo , Pirenos/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Ochrobactrum/isolamento & purificação , Microbiologia do Solo , Temperatura
10.
World J Microbiol Biotechnol ; 35(4): 55, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30900049

RESUMO

Bacteria in natural associations with agricultural crops are promising for use in the improvement of clonal micropropagation of plants. We clarified the taxonomic position of Ochrobactrum cytisi strain IPA7.2 and investigated its tolerance for salinity, high temperature, and glyphosate pollution. We also tested the strain's potential to promote the growth of potato (Solanum tuberosum L.) microplants. Using the IPA7.2 draft genome (no. NZ_MOEC00000000), we searched for housekeeping genes and also for the target genes encoding glyphosate tolerance and plant-growth-promoting ability. A multilocus sequence analysis of the gap, rpoB, dnaK, trpE, aroC, and recA housekeeping genes led us to identify isolate IPA7.2 as O. cytisi. The strain tolerated temperatures up to 50 °C and NaCl concentrations up to 3-4%, and it produced 8 µg ml-1 of indole-3-acetic acid. It also tolerated 6 mM glyphosate owing to the presence of type II 5-enolpyruvylshikimate-3-phosphate synthase. Finally, it was able to colonize the roots and tissues of potato microplants, an ability preserved by several generations after subculturing. We identified the development phase of potato microplants that was optimal for inoculation with O. cytisi IPA7.2. Inoculation of in vitro-grown 15-day-old microplants increased the mitotic index of root meristem cells (by 50%), the length of shoots (by 34%), the number of leaves (by 7%), and the number of roots (by 16%). Under ex vitro conditions, the inoculated plants had a greater leaf area (by 77%) and greater shoot and root dry weight (by 84 and 61%, respectively) than did the control plants. We recommend O. cytisi IPA 7.2 for use in the growing of potato microplants to improve the production of elite seed material.


Assuntos
Ochrobactrum/fisiologia , Desenvolvimento Vegetal , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/microbiologia , Estresse Fisiológico , Genes Bacterianos/genética , Genes Essenciais/genética , Glicina/efeitos adversos , Glicina/análogos & derivados , Ácidos Indolacéticos/metabolismo , Tipagem de Sequências Multilocus , Ochrobactrum/classificação , Ochrobactrum/genética , Ochrobactrum/isolamento & purificação , Filogenia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , RNA Ribossômico 16S/genética , Salinidade , Tolerância ao Sal , Cloreto de Sódio , Microbiologia do Solo , Termotolerância
11.
Int. microbiol ; 22(1): 29-39, mar. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184811

RESUMO

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


No disponible


Assuntos
Animais , Bacillus/isolamento & purificação , Celulose/metabolismo , Intestinos/microbiologia , Isópteros/microbiologia , Lignina/metabolismo , Ochrobactrum/isolamento & purificação , Ochrobactrum/metabolismo , Polissacarídeos/metabolismo , Ração Animal , Bacillus/metabolismo , Glucose/metabolismo , Hidrólise , Madeira , Xilanos/metabolismo , Xilose/metabolismo
12.
Int Microbiol ; 22(1): 29-39, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30810928

RESUMO

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


Assuntos
Bacillus/isolamento & purificação , Celulose/metabolismo , Intestinos/microbiologia , Isópteros/microbiologia , Lignina/metabolismo , Ochrobactrum/isolamento & purificação , Polissacarídeos/metabolismo , Ração Animal , Animais , Bacillus/metabolismo , Glucose/metabolismo , Hidrólise , Ochrobactrum/metabolismo , Madeira , Xilanos/metabolismo , Xilose/metabolismo
13.
Bioresour Technol ; 272: 442-450, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30388582

RESUMO

Nitrogen contaminants are widespread presence in municipal wastewater, heterotrophic nitrification and aerobic denitrification (HN-AD) bacteria have advantages of dealing with multiple nitrogen. Strain LJ81 was isolated from domestic sludge, identified as Ochrobactrum anthropic, which was oxygen-dependent and could survive in a wide range of pH values. Results showed that strain LJ81 could achieve simultaneous nitrification and denitrification (SND) under aerobic condition, whilst more than 80% of initial nitrogen was converted into gaseous nitrogen. The removal rates of ammonia increased from 3.75 to 3.85 and 5.70 mg-N L-1 h-1 by adding nitrite and nitrate, respectively, while the nitrate denitrification was the rate-limiting step of SND process. Moreover, adding chlorate could inhibit not only the cell growth slightly but also denitrification of nitrate. All results indicated that O. anthropic strain LJ81 exhibited excellent performance on nitrogen removal without nitrite accumulation under aerobic condition.


Assuntos
Ochrobactrum/metabolismo , Aerobiose , Amônia/metabolismo , Desnitrificação , Processos Heterotróficos , Nitratos/metabolismo , Nitrificação , Nitritos/metabolismo , Nitrogênio/metabolismo , Ochrobactrum/isolamento & purificação , Oxigênio/metabolismo , Esgotos/microbiologia
14.
J Microbiol Biotechnol ; 28(7): 1122-1132, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-29913551

RESUMO

In this study, we attempted to find new and efficient microbial enzymes for producing rare sugars. A ribose-5-phosphate isomerase B (OsRpiB) was cloned, overexpressed, and preliminarily purified successfully from a newly screened Ochrobactrum sp. CSL1, which could catalyze the isomerization reaction of rare sugars. A study of its substrate specificity showed that the cloned isomerase (OsRpiB) could effectively catalyze the conversion of L-rhamnose to L-rhamnulose, which was unconventional for RpiB. The optimal reaction conditions (50°C, pH 8.0, and 1 mM Ca2+) were obtained to maximize the potential of OsRpiB in preparing L-rhamnulose. The catalytic properties of OsRpiB, including Km, kcat, and catalytic efficiency (kcat/Km), were determined as 43.47 mM, 129.4 sec-1, and 2.98 mM/sec. The highest conversion rate of L-rhamnose under the optimized conditions by OsRpiB could reach 26% after 4.5 h. To the best of our knowledge, this is the first successful attempt of the novel biotransformation of L-rhamnose to L-rhamnulose by OsRpiB biocatalysis.


Assuntos
Aldose-Cetose Isomerases/química , Aldose-Cetose Isomerases/metabolismo , Ochrobactrum/enzimologia , Ramnose/metabolismo , Aldose-Cetose Isomerases/genética , Sequência de Aminoácidos , Domínio Catalítico , Clonagem Molecular , DNA Bacteriano/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Cinética , Ochrobactrum/isolamento & purificação , Conformação Proteica , Proteínas Recombinantes , Ramnose/química , Alinhamento de Sequência , Análise de Sequência de Proteína , Especificidade por Substrato
15.
Environ Sci Pollut Res Int ; 25(14): 14171-14181, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29524172

RESUMO

Bacterial systems have drawn an increasing amount of attention on lignin valorization due to their rapid growth and powerful environmental adaptability. In this study, Klebsiella pneumoniae NX-1, Pseudomonas putida NX-1, and Ochrobactrum tritici NX-1 with ligninolytic potential were isolated from leaf mold samples. Their ligninolytic capabilities were determined by measuring (1) the cell growth on kraft lignin as the sole carbon source, (2) the decolorization of kraft lignin and lignin-mimicking dyes, (3) the micro-morphology changes and transformations of chemical groups in kraft lignin, and (4) the ligninolytic enzyme activities of these three isolates. To the best of our knowledge, this is the first report that Ochrobactrum tritici species can depolymerize and metabolize lignin. Moreover, laccase, lignin peroxidase, and Mn-peroxidase showed high activities in P. putida NX-1. Due to their excellent ligninolytic capabilities, these three bacteria are important supplements to ligninolytic bacteria library and could be valuable in lignin valorization.


Assuntos
Poluentes Ambientais/análise , Klebsiella pneumoniae/isolamento & purificação , Lignina/análise , Ochrobactrum/isolamento & purificação , Pseudomonas putida/isolamento & purificação , Biodegradação Ambiental , Klebsiella pneumoniae/metabolismo , Lacase/metabolismo , Ochrobactrum/metabolismo , Peroxidases/metabolismo , Folhas de Planta/microbiologia , Pseudomonas putida/metabolismo
16.
N Biotechnol ; 43: 37-43, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28720419

RESUMO

Piracetam (2-oxo-1-pyrrolidine acetamide) is a popular cognitive enhancer, which has recently been detected in waste and drinking water. Nootropic drugs are designed to affect human metabolism and act on the nervous system, but their environmental effects have yet to be the subject of detailed studies. In this report, we present the efficient biodegradation of the cognitive enhancer, piracetam. Two bacterial strains capable of using this compound as the sole carbon source were isolated and later identified as Ochrobactrum anthropi strain MW6 and Ochrobactrum intermedium strain MW7. The compound's mineralization and the cleavage of the heterocyclic ring were shown in the experiments with 14C-labeled piracetam. This is also the first report of a pharmaceutical's degradation by the Ochrobactrum genus. This study presents model microorganisms that can be used in further investigation of piracetam's degradation pathways as well as enzymes and genes involved in the process.


Assuntos
Nootrópicos/metabolismo , Ochrobactrum/metabolismo , Piracetam/metabolismo , Cromatografia Líquida de Alta Pressão , Ochrobactrum/crescimento & desenvolvimento , Ochrobactrum/isolamento & purificação , Piracetam/análise
17.
Microb Cell Fact ; 16(1): 215, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29183326

RESUMO

BACKGROUND: Bacteria have developed different mechanisms for the transformation of metalloid oxyanions to non-toxic chemical forms. A number of bacterial isolates so far obtained in axenic culture has shown the ability to bioreduce selenite and tellurite to the elemental state in different conditions along with the formation of nanoparticles-both inside and outside the cells-characterized by a variety of morphological features. This reductive process can be considered of major importance for two reasons: firstly, toxic and soluble (i.e. bioavailable) compounds such as selenite and tellurite are converted to a less toxic chemical forms (i.e. zero valent state); secondly, chalcogen nanoparticles have attracted great interest due to their photoelectric and semiconducting properties. In addition, their exploitation as antimicrobial agents is currently becoming an area of intensive research in medical sciences. RESULTS: In the present study, the bacterial strain Ochrobactrum sp. MPV1, isolated from a dump of roasted arsenopyrites as residues of a formerly sulfuric acid production near Scarlino (Tuscany, Italy) was analyzed for its capability of efficaciously bioreducing the chalcogen oxyanions selenite (SeO32-) and tellurite (TeO32-) to their respective elemental forms (Se0 and Te0) in aerobic conditions, with generation of Se- and Te-nanoparticles (Se- and TeNPs). The isolate could bioconvert 2 mM SeO32- and 0.5 mM TeO32- to the corresponding Se0 and Te0 in 48 and 120 h, respectively. The intracellular accumulation of nanomaterials was demonstrated through electron microscopy. Moreover, several analyses were performed to shed light on the mechanisms involved in SeO32- and TeO32- bioreduction to their elemental states. Results obtained suggested that these oxyanions are bioconverted through two different mechanisms in Ochrobactrum sp. MPV1. Glutathione (GSH) seemed to play a key role in SeO32- bioreduction, while TeO32- bioconversion could be ascribed to the catalytic activity of intracellular NADH-dependent oxidoreductases. The organic coating surrounding biogenic Se- and TeNPs was also characterized through Fourier-transform infrared spectroscopy. This analysis revealed interesting differences among the NPs produced by Ochrobactrum sp. MPV1 and suggested a possible different role of phospholipids and proteins in both biosynthesis and stabilization of such chalcogen-NPs. CONCLUSIONS: In conclusion, Ochrobactrum sp. MPV1 has demonstrated to be an ideal candidate for the bioconversion of toxic oxyanions such as selenite and tellurite to their respective elemental forms, producing intracellular Se- and TeNPs possibly exploitable in biomedical and industrial applications.


Assuntos
Arsenicais/metabolismo , Compostos de Ferro/metabolismo , Nanopartículas Metálicas/química , Minerais/metabolismo , Ochrobactrum/metabolismo , Ácido Selenioso/metabolismo , Sulfetos/metabolismo , Telúrio/metabolismo , Aerobiose , Cultura Axênica/métodos , Catálise , Itália , Microscopia Eletrônica , Ochrobactrum/química , Ochrobactrum/isolamento & purificação , Ochrobactrum/ultraestrutura , Selênio/química , Selênio/metabolismo , Telúrio/química
18.
J Glob Antimicrob Resist ; 11: 133-137, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29111479

RESUMO

OBJECTIVES: Bacteria belonging to the genera Ochrobactrum and Achromobacter are bacteria considered opportunistic, causing infections mainly in immunocompromised patients. ß-lactamases are the main cause of resistance to ß-lactam antibiotics. This study aimed to investigate the antimicrobial resistance profile and the presence of ß-lactamases encoding genes in Ochrobactrum sp. and Achromobacter sp. isolated from Brazilian soils. METHODS: Soil samples from the five regions of Brazil were collected for the isolation of bacteria, which were identified molecularly and then, the minimum inhibitory concentration and detection of ß-lactamases encoding genes were performed. RESULTS: High-level of resistance to ß-lactam antibiotics and different ß-lactamases encoding genes were found (blaCTX-M-Gp1, blaSHV, blaOXA-1-like and blaKPC), including the first report of the presence of blaKPC in bacteria belonging to the genera Ochrobactrum and Achromobacter. CONCLUSION: The results showed that the bacteria from this study, belonging to genera Ochrobactrum and Achromobacter isolated from soil, harbor different ß-lactamases encoding genes and can act as a reservoir of these genes.


Assuntos
Achromobacter/isolamento & purificação , Ochrobactrum/isolamento & purificação , beta-Lactamases/genética , beta-Lactamas/farmacologia , Achromobacter/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Brasil , Testes de Sensibilidade Microbiana , Ochrobactrum/genética , Microbiologia do Solo , Resistência beta-Lactâmica
19.
Lipids Health Dis ; 16(1): 177, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28923075

RESUMO

BACKGROUND: Alkaline thermostable lipase and biosurfactant producing bacteria are very interested at detergent applications, not only because of their eco-friendly characterize, but alsoproduction lipase and biosurfactant by using cheap materials. Ochrobactrum intermedium strain MZV101 was isolated as washing powder resistant, alkaline thermostable lipase and biosurfactant producing bacterium in order to use at detergent applications. METHODS: O. intermedium strain MZV101 produces was lipase and biosurfactant in the same media with pH 10 and temperature of 60 °C. Washing test and some detergent compatibility character of lipase enzyme and biosurfactant were assayed. The antimicrobial activity evaluated against various bacteria and fungi. RESULTS: Lipase and biosurfactant produced by O. intermedium strain MZV101 exhibited high stability at pH 10-13 and temperature of 70-90 °C, biosurfactant exhibits good stability at pH 9-13 and thermostability in all range. Both lipase and biosurfactant were found to be stable in the presence of different metal ions, detergents and organic solvents. The lipase enzyme extracted using isopropanol with yield of 69.2% and biosurfactant with ethanol emulsification index value of 70.99% and yield of 9.32 (g/l). The single band protein after through from G-50 Sephadex column on SDS-PAGE was calculated to be 99.42 kDa. Biosurfactant O. intermedium strain MZV101 exhibited good antimicrobial activity against Gram-negative bacteria and against various bacterial pathogens. Based upon washing test biosurfactant and lipase O. intermedium strain MZV101considered being strong oil removal. CONCLUSION: The results of this study indicate that isolated lipase and biosurfactant with strong oil removal, antimicrobial activity and good stability could be useful for detergent applications.


Assuntos
Proteínas de Bactérias/metabolismo , Detergentes/química , Lipase/metabolismo , Ochrobactrum/metabolismo , Tensoativos/metabolismo , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/isolamento & purificação , Concentração de Íons de Hidrogênio , Lipase/isolamento & purificação , Ochrobactrum/enzimologia , Ochrobactrum/genética , Ochrobactrum/isolamento & purificação , Reação em Cadeia da Polimerase , Solventes/química , Tensoativos/farmacologia , Temperatura
20.
Artigo em Inglês | MEDLINE | ID: mdl-28463567

RESUMO

This study employed the use of 16S rRNA gene sequence analysis to identify three of four native bacterial strains isolated from crude oil-contaminated site in Poza Rica, Veracruz, Mexico. The identified bacteria were Ochrobactrum intermedium, Pandoraea pnomenusa and Ochrobactrum sp., but SA2-09 strain was not identified. The ability of the isolates to degrade polycyclic aromatic hydrocarbons (PAHs) was evaluated at 31.61 and 54.52 mg/kg PAHs in soil, when used as crude oil in soil microcosm during 80 days of incubation at 30°C. The results demonstrated that O. intermedium biodegraded many PAHs, including the high molecular weight (HMW) PAHs fluoranthene (100% equivalent 0.24 mg/kg), benzo [b] fluoranthene (81.8% equal 0.18 mg/kg), Benzo[a]pyrene (87.0%, 0.20 mg/kg) and Benzo[g,h,i]perylene (52.7%, 0.39 mg/kg). P. pnomenusa had a degradation profile of HMW PAHs, which was similar to O. intermedium, while Ochrobactrum sp. and the strain SA-09 exhibited lower degradation rates of HMW.


Assuntos
Burkholderia/isolamento & purificação , Ochrobactrum/isolamento & purificação , Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Biodegradação Ambiental , México , Filogenia , RNA Ribossômico 16S/genética
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