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1.
Braz. j. microbiol ; 49(2): 269-278, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-889232

ABSTRACT

Abstract A total of 276 endophytic bacteria were isolated from the root nodules of soybean (Glycine max L.) grown in 14 sites in Henan Province, China. The inhibitory activity of these bacteria against pathogenic fungus Phytophthora sojae 01 was screened in vitro. Six strains with more than 63% inhibitory activities were further characterized through optical epifluorescence microscopic observation, sequencing, and phylogenetic analysis of 16S rRNA gene, potential plant growth-promoting properties analysis, and plant inoculation assay. On the basis of the phylogeny of 16S rRNA genes, the six endophytic antagonists were identified as belonging to five genera: Enterobacter, Acinetobacter, Pseudomonas, Ochrobactrum, and Bacillus. The strain Acinetobacter calcoaceticus DD161 had the strongest inhibitory activity (71.14%) against the P. sojae 01, which caused morphological abnormal changes of fungal mycelia; such changes include fracture, lysis, formation of a protoplast ball at the end of hyphae, and split ends. Except for Ochrobactrum haematophilum DD234, other antagonistic strains showed the capacity to produce siderophore, indole acetic acid, and nitrogen fixation activity. Regression analysis suggested a significant positive correlation between siderophore production and inhibition ratio against P. sojae 01. This study demonstrated that nodule endophytic bacteria are important resources for searching for inhibitors specific to the fungi and for promoting effects for soybean seedlings.


Subject(s)
Plant Growth Regulators/metabolism , Soybeans/growth & development , Soybeans/microbiology , Bacteria/isolation & purification , Root Nodules, Plant/microbiology , Endophytes/isolation & purification , Antibiosis , Phylogeny , Phytophthora/cytology , Phytophthora/growth & development , Phytophthora/drug effects , Bacteria/classification , Bacteria/metabolism , DNA, Ribosomal/genetics , DNA, Ribosomal/chemistry , RNA, Ribosomal, 16S/genetics , Cluster Analysis , China , Sequence Analysis, DNA , Endophytes/classification , Endophytes/metabolism
2.
Braz. j. microbiol ; 49(2): 248-257, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-889237

ABSTRACT

Abstract In this study for the first-time microbial communities in the caves located in the mountain range of Hindu Kush were evaluated. The samples were analyzed using culture-independent (16S rRNA gene amplicon sequencing) and culture-dependent methods. The amplicon sequencing results revealed a broad taxonomic diversity, including 21 phyla and 20 candidate phyla. Proteobacteria were dominant in both caves, followed by Bacteroidetes, Actinobacteria, Firmicutes, Verrucomicrobia, Planctomycetes, and the archaeal phylum Euryarchaeota. Representative operational taxonomic units from Koat Maqbari Ghaar and Smasse-Rawo Ghaar were grouped into 235 and 445 different genera, respectively. Comparative analysis of the cultured bacterial isolates revealed distinct bacterial taxonomic profiles in the studied caves dominated by Proteobacteria in Koat Maqbari Ghaar and Firmicutes in Smasse-Rawo Ghaar. Majority of those isolates were associated with the genera Pseudomonas and Bacillus. Thirty strains among the identified isolates from both caves showed antimicrobial activity. Overall, the present study gave insight into the great bacterial taxonomic diversity and antimicrobial potential of the isolates from the previously uncharacterized caves located in the world's highest mountains range in the Indian sub-continent.


Subject(s)
Bacteria/isolation & purification , Bacteria/classification , Environmental Microbiology , Biota , Antibiosis , Pakistan , Phylogeny , Bacteria/growth & development , Bacteria/genetics , DNA, Bacterial/genetics , DNA, Bacterial/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal/chemistry , RNA, Ribosomal, 16S/genetics , Cluster Analysis , Sequence Analysis, DNA , Euryarchaeota/isolation & purification , Euryarchaeota/classification , Euryarchaeota/growth & development , Euryarchaeota/genetics , DNA, Archaeal/genetics , DNA, Archaeal/chemistry , Metagenomics
3.
Braz. j. microbiol ; 48(2): 305-313, April.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-839385

ABSTRACT

Abstract The aerobic degradation of aromatic compounds by bacteria is performed by dioxygenases. To show some characteristic patterns of the dioxygenase genotype and its degradation specificities, twenty-nine gram-negative bacterial cultures were obtained from sediment contaminated with phenolic compounds in Wuhan, China. The isolates were phylogenetically diverse and belonged to 10 genera. All 29 gram-negative bacteria were able to utilize phenol, m-dihydroxybenzene and 2-hydroxybenzoic acid as the sole carbon sources, and members of the three primary genera Pseudomonas, Acinetobacter and Alcaligenes were able to grow in the presence of multiple monoaromatic compounds. PCR and DNA sequence analysis were used to detect dioxygenase genes coding for catechol 1,2-dioxygenase, catechol 2,3-dioxygenase and protocatechuate 3,4-dioxygenase. The results showed that there are 4 genotypes; most strains are either PNP (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is positive) or PNN (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is negative). The strains with two dioxygenase genes can usually grow on many more aromatic compounds than strains with one dioxygenase gene. Degradation experiments using a mixed culture representing four bacterial genotypes resulted in the rapid degradation of phenol. Determinations of substrate utilization and phenol degradation revealed their affiliations through dioxygenase genotype data.


Subject(s)
Phenol/metabolism , Dioxygenases/genetics , Dioxygenases/metabolism , Gram-Negative Bacteria/enzymology , Gram-Negative Bacteria/metabolism , Phylogeny , Pseudomonas , Soil Pollutants/metabolism , Acinetobacter , DNA, Bacterial/genetics , DNA, Bacterial/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal/chemistry , Carbon/metabolism , RNA, Ribosomal, 16S/genetics , Biotransformation , Cluster Analysis , China , Polymerase Chain Reaction , Sequence Analysis, DNA , Geologic Sediments/microbiology , Alcaligenes , Environmental Pollution , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/genetics
4.
Braz. j. microbiol ; 47(1): 18-24, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775112

ABSTRACT

Abstract Phenol and phenolic compounds are environmental pollutants present in industrial wastewaters such as coal tar, oil refineries and petrochemical plants. Phenol removal from industrial effluents is extremely important for the protection of environment. Usually, phenol degradation is carried out by physicochemical methods that are costly and produce hazardous metabolites. Recently, phenol biodegradation has been considered. Yeasts are the most important phenol biodegraders. In this study, the phenol-degrading yeast from environmental samples (soil and wastewater) was isolated from the coking plant of Zarand, Kerman. Then total heterotrophic yeasts were counted. The soil samples had higher rates of yeast degrader, in comparison to wastewater samples. After three passages, four yeasts (K1, K2, K7 and K11) that had the highest growth rate were selected for further study. Also, these yeasts were able to remove phenol measured by Gibbs reagent. The effect of four different concentrations of phenol (50, 125, 200 and 275) mg L−1 was measured and three degradation patterns in these yeasts were observed. The hydrophobicity and emulsification activity were measured in all eleven yeasts. Finally, strong yeasts in phenol degrading yeasts were identified by molecular method using amplification of 18S rRNA gene region. The sequencing results showed that these isolated yeasts belonged to Candida tropicalis strain K1, Pichia guilliermondii strain K2, Meyerozyma guilliermondii strain K7 and C. tropicalis strain K11.


Subject(s)
Industrial Waste , Phenol/metabolism , Waste Water/microbiology , Water Pollutants, Chemical/metabolism , Yeasts/classification , Yeasts/metabolism , Biotransformation , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Iran , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Soil Microbiology , Yeasts/genetics , Yeasts/isolation & purification
5.
Braz. j. microbiol ; 47(1): 85-95, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775117

ABSTRACT

Abstract The main objective of the present study was to isolate and characterize actinomycetes for their plant growth-promotion in chickpea. A total of 89 actinomycetes were screened for their antagonism against fungal pathogens of chickpea by dual culture and metabolite production assays. Four most promising actinomycetes were evaluated for their physiological and plant growth-promotion properties under in vitro and in vivo conditions. All the isolates exhibited good growth at temperatures from 20 °C to 40 °C, pH range of 7–11 and NaCl concentrations up to 8%. These were also found highly tolerant to Bavistin, slightly tolerant to Thiram and Captan (except VAI-7 and VAI-40) but susceptible to Benlate and Ridomil at field application levels and were found to produce siderophore, cellulase, lipase, protease, chitinase (except VAI-40), hydrocyanic acid (except VAI-7 and VAI-40), indole acetic acid and β-1,3-glucanase. When the four actinomycetes were evaluated for their plant growth-promotion properties under field conditions on chickpea, all exhibited increase in nodule number, shoot weight and yield. The actinomycetes treated plots enhanced total N, available P and organic C over the un-inoculated control. The scanning electron microscope studies exhibited extensive colonization by actinomycetes on the root surface of chickpea. The expression profiles for indole acetic acid, siderophore and β-1,3-glucanase genes exhibited up-regulation for all three traits and in all four isolates. The actinomycetes were identified as Streptomyces but different species in the 16S rDNA analysis. It was concluded that the selected actinomycetes have good plant growth-promotion and biocontrol potentials on chickpea.


Subject(s)
Actinobacteria/growth & development , Cicer/growth & development , Soil Microbiology , Actinobacteria/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Molecular Sequence Data , Phylogeny , Plant Growth Regulators/metabolism , Rhizosphere , /genetics , Sequence Analysis, DNA , Soil , Sodium Chloride/metabolism , Temperature
6.
Braz. j. microbiol ; 47(1): 1-9, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775132

ABSTRACT

Abstract This study was conducted to isolate an acid-producing, alkaliphilic bacterium to reduce the alkalinity of cement industry waste (cement kiln dust). Gram-positive isolate KG1 grew well at pH values of 6–12, temperatures of 28–50 °C, and NaCl concentrations of 0–16% and thus was further screened for its potential to reduce the pH of an alkaline medium. Phenotypic characteristics of the KG1 isolate were consistent with those of the genus Bacillus, and the highest level of 16S rRNA gene sequence similarity was found with Bacillus halodurans strain DSM 497 (94.7%). On the basis of its phenotypic characteristics and genotypic distinctiveness from other phylogenetic neighbors belonging to alkaliphilic Bacillus species, the isolated strain was designated B. halodurans strain KG1, with GenBank accession number JQ307184 (= NCIM 5439). Isolate KG1 reduced the alkalinity (by 83.64%) and the chloride content (by 86.96%) of cement kiln dust and showed a potential to be used in the cement industry for a variety of applications.


Subject(s)
Bacillus/growth & development , Bacillus/metabolism , Biotechnology/methods , Industrial Waste , Waste Management/methods , Bacterial Typing Techniques , Bacillus/classification , Bacillus/isolation & purification , Cluster Analysis , Construction Materials , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , Temperature
7.
Braz. j. microbiol ; 46(4): 1183-1191, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769666

ABSTRACT

Abstract Adhirasam is a cereal based, doughnut shaped, deep fried dessert consumed in the southern regions of India. The dough used to prepare adhirasam is fermented and contains rice flour and jaggery. The aim of the present study was to characterize the cultivable bacteria associated with this fermented dough and to identify a suitable starter culture for the production of quality adhirasam. In total, one hundred and seventy bacterial isolates were recovered from de Man Rogosa Sharp (MRS) agar, nutrient agar, lysogeny agar and tryptic soy agar media. Out of the 170 bacterial isolates, sixteen isolates were selected based on their ability to tolerate glucose and sucrose. All the bacterial isolates tolerated 15% glucose and 30% sucrose. Analyses of 16S rDNA gene sequences of the bacterial isolates showed that the dominant cultivable bacteria were members of the genus Bacillus. These strains were further used as starters and tested for their ability to ferment rice flour with jaggery to produce adhirasam dough. Organoleptic evaluation was carried out to choose the best starter strain. Adhirasam prepared from Bacillus subtilis isolates S4-P11, S2-G2-A1 and S1-G15, Bacillus tequilensis isolates S2-H16, S3-P9, S3-G10 and Bacillus siamensis isolate S2-G13 were highly acceptable to consumers. Adhirasam prepared using these starter cultures had superior product characteristics such as softness in texture, flavor and enhanced aroma and sweet taste.


Subject(s)
Humans , Bacillus/growth & development , Bacillus/metabolism , Food Microbiology , Bacterial Typing Techniques , Bacillus/classification , Bacillus/isolation & purification , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , India , Oryza/metabolism , /genetics , Sequence Analysis, DNA
8.
Braz. j. microbiol ; 46(4): 1147-1154, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769668

ABSTRACT

Abstract Pseudomonas aeruginosa, in spite of being a ubiquitous organism (as it is found in soil, water, and humans), is also an opportunistic pathogen. In order to maintain its diversity in the community, it produces various toxic proteins, known as, bacteriocins. In the present study, pyocin SA189, which is a bacteriocin produced by P. aeruginosa SA189 (isolated from a clinical sample) was characterized. P. aeruginosa SA189, as identified by the conventional and 16S rRNA gene amplification, produced pyocin SA189 of molecular weight of 66 k Da. The pyocin showed antimicrobial activity against several clinically relevant Gram-positive and Gram-negative bacteria and was substantially stable for wide ranges of temperature and pH. Furthermore, the pyocin also retained its biological activity upon treatment with metal ions, organic solvents, and various proteolytic and lipolytic enzymes. The data from the growth kinetics indicated that the maximum bacteriocin production occurred in the late log phase. Overall, our results signify the potential of pyocin SA189 as a bio-control agent.


Subject(s)
Pseudomonas aeruginosa/metabolism , Pyocins/isolation & purification , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Host Specificity , Hydrogen-Ion Concentration , Molecular Weight , Pseudomonas aeruginosa/genetics , Pyocins/chemistry , /genetics , Sequence Analysis, DNA , Temperature
9.
Braz. j. microbiol ; 46(2): 443-453, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749707

ABSTRACT

The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240) thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5%) represented by B. licheniformis (119), B. aerius (44), B. sonorensis (33), B. subtilis (subsp. spizizenii (2) and subsp. inaquosurum (6)), B. amyloliquefaciens (subsp. amyloliquefaciens (4) and subsp. plantarum (4)), B. tequilensis (3), B. pumilus (3) and Bacillus sp. (19). Only six isolates (2.5%) belonged to the genus Aeribacillus represented by A. pallidus (4) and Aeribacillus sp. (2). In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.


Subject(s)
Bacillaceae/classification , Bacillaceae/isolation & purification , Gram-Positive Rods/classification , Gram-Positive Rods/isolation & purification , Hot Springs/microbiology , Soil Microbiology , Water Microbiology , Biodiversity , Bacillaceae/genetics , Bacillaceae/radiation effects , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Gram-Positive Rods/genetics , Gram-Positive Rods/radiation effects , Molecular Sequence Data , Morocco , Phylogeny , /genetics , Sequence Analysis, DNA , Spores, Bacterial/cytology
10.
Braz. j. microbiol ; 46(2): 631-637, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749708

ABSTRACT

This work addresses the production of prodigiosin from ram horn peptone (RHP) using MO-1, a local isolate in submerged culture. First, a novel gram-negative and rod-shaped bacterial strain, MO-1, was isolated from the body of the grasshopper (Poecilemon tauricola Ramme 1951), which was collected from pesticide-contaminated fields. Sequence analysis of 16S rDNA classified the microbe as Serratia marcescens. The substrate utilization potential (BIOLOG) and fatty acid methyl ester profile (FAME) of S. marcescens were also determined. The effect of RHP on the production of prodigiosin by S. marcescens MO-1 was investigated, and the results showed that RHP supplementation promoted the growth of MO-1 and increased the production of prodigiosin. A concentration of 0.4% (w/v) RHP resulted in the greatest yield of prodigiosin (277.74 mg/L) after 48 h when mannitol was used as the sole source of carbon. The pigment yield was also influenced by the types of carbon sources and peptones. As a result, RHP was demonstrated to be a suitable substrate for prodigiosin production. These results revealed that prodigiosin could be produced efficiently by S. marcescens using RHP.


Subject(s)
Animals , Culture Media/chemistry , Peptones/metabolism , Prodigiosin/metabolism , Serratia marcescens/growth & development , Serratia marcescens/metabolism , Bacterial Typing Techniques , Cluster Analysis , Cytosol/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fatty Acids/analysis , Grasshoppers/microbiology , Molecular Sequence Data , Phylogeny , Pigments, Biological/metabolism , /genetics , Sequence Analysis, DNA , Serratia marcescens/classification , Serratia marcescens/isolation & purification
11.
Braz. j. microbiol ; 46(2): 425-432, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749712

ABSTRACT

The strain JPL-2, capable of degrading fenoxaprop-P-ethyl (FE), was isolated from the soil of a wheat field and identified as Rhodococcus ruber. This strain could utilize FE as its sole carbon source and degrade 94.6% of 100 mg L−1 FE in 54 h. Strain JPL-2 could also degrade other aryloxyphenoxy propanoate (AOPP) herbicides. The initial step of the degradation pathway is to hydrolyze the carboxylic acid ester bond. A novel esterase gene feh, encoding the FE-hydrolyzing carboxylesterase (FeH) responsible for this initial step, was cloned from strain JPL-2. Its molecular mass was approximately 39 kDa, and the catalytic efficiency of FeH followed the order of FE > quizalofop-P-ethyl > clodinafop-propargyl > cyhalofop-butyl > fluazifop-P-butyl > haloxyfop-P-methyl > diclofop-methy, which indicated that the chain length of the alcohol moiety strongly affected the hydrolysis activity of the FeH toward AOPP herbicides.


Subject(s)
Carboxylesterase/genetics , Carboxylesterase/metabolism , Herbicides/metabolism , Oxazoles/metabolism , Propionates/metabolism , Rhodococcus/isolation & purification , Rhodococcus/metabolism , Biotransformation , Cloning, Molecular , Cluster Analysis , Carboxylesterase/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , Molecular Weight , Phylogeny , /genetics , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Rhodococcus/enzymology , Rhodococcus/genetics , Sequence Analysis, DNA , Soil Microbiology , Substrate Specificity , Triticum/growth & development
12.
Braz. j. microbiol ; 46(2): 433-441, Apr-Jun/2015. graf
Article in English | LILACS | ID: lil-749723

ABSTRACT

An indigenous bacterial strain capable of utilizing 2,4-dichlorophenoxyacetic acid as the sole carbon and energy source was isolated from a soil used for grown wheat with a long-term history of herbicide use in Beijing, China. The strain BJ71 was identified as Cupriavidus campinensis based on its 16S rRNA sequence analysis and morphological, physiological, and biochemical characteristics. The degradation characteristics of strain BJ71 were evaluated. The optimal conditions for 2,4-D degradation were as follows: pH 7.0, 30 °C, 3% (v/v) inoculum size, and an initial 2,4-D concentration of 350 mg L−1. Up to 99.57% of the 2,4-D was degraded under optimal conditions after 6 days of incubation. Strain BJ71 was also able to degrade quizalofop and fluroxypyr. This is the first report of a 2,4-D-degrader containing tfdA gene that can utilize these two herbicides. In a biodegradation experiment, 87.13% and 42.53% of 2,4-D (initial concentration, 350 mg kg−1) was degraded in non-sterile and sterilized soil inoculated with BJ71, respectively, after 14 days. The 2,4-D degradation was more rapid in a soil microcosm including BJ71 than in a soil microcosm without BJ71. These results indicate that strain BJ71 is a potential candidate for the bioremediation of soil contaminated with the herbicide 2,4-D.


Subject(s)
Cupriavidus/isolation & purification , Cupriavidus/metabolism , Herbicides/metabolism , /metabolism , Acetates/metabolism , Bacteriological Techniques , Biotransformation , China , Cluster Analysis , Cupriavidus/genetics , Cupriavidus/physiology , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Molecular Sequence Data , Phylogeny , Propionates/metabolism , Pyridines/metabolism , Quinoxalines/metabolism , /genetics , Sequence Analysis, DNA , Temperature , Time Factors , Triticum
13.
Braz. j. microbiol ; 46(2): 377-387, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749728

ABSTRACT

Three bacterial isolates identified as Alcanivorax borkumensis SK2, Rhodococcus erythropolis HS4 and Pseudomonas stutzeri SDM, based on 16S rRNA gene sequences, were isolated from crude oil enrichments of natural seawater. Single strains and four bacterial consortia designed by mixing the single bacterial cultures respectively in the following ratios: (Alcanivorax: Pseudomonas, 1:1), (Alcanivorax: Rhodococcus, 1:1), (Pseudomonas: Rhodococcus, 1:1), and (Alcanivorax: Pseudomonas: Rhodococcus, 1:1:1), were analyzed in order to evaluate their oil degrading capability. All experiments were carried out in microcosms systems containing seawater (with and without addition of inorganic nutrients) and crude oil (unique carbon source). Measures of total and live bacterial abundance, Card-FISH and quali-, quantitative analysis of hydrocarbons (GC-FID) were carried out in order to elucidate the co-operative action of mixed microbial populations in the process of biodegradation of crude oil. All data obtained confirmed the fundamental role of bacteria belonging to Alcanivorax genus in the degradation of linear hydrocarbons in oil polluted environments.


Subject(s)
Alcanivoraceae/metabolism , Petroleum/metabolism , Pseudomonas stutzeri/metabolism , Rhodococcus/metabolism , Alcanivoraceae/classification , Alcanivoraceae/genetics , Alcanivoraceae/isolation & purification , Biotransformation , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Microbial Consortia , Molecular Sequence Data , Phylogeny , Pseudomonas stutzeri/classification , Pseudomonas stutzeri/genetics , Pseudomonas stutzeri/isolation & purification , /genetics , Rhodococcus/classification , Rhodococcus/genetics , Rhodococcus/isolation & purification , Sequence Analysis, DNA , Seawater/microbiology
14.
Braz. j. microbiol ; 46(2): 347-354, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749729

ABSTRACT

Halophilic microorganisms are able to grow in the presence of salt and are also excellent source of enzymes and biotechnological products, such as exopolysaccharides (EPSs) and polyhydroxyalkanoates (PHAs). Salt-tolerant bacteria were screened in the Organic Composting Production Unit (OCPU) of São Paulo Zoological Park Foundation, which processes 4 ton/day of organic residues including plant matter from the Atlantic Rain Forest, animal manure and carcasses and mud from water treatment. Among the screened microorganisms, eight halotolerant bacteria grew at NaCl concentrations up to 4 M. These cultures were classified based on phylogenetic characteristics and comparative partial 16S rRNA gene sequence analysis as belonging to the genera Staphylococcus, Bacillus and Brevibacterium. The results of this study describe the ability of these halotolerant bacteria to produce some classes of hydrolases, namely, lipases, proteases, amylases and cellulases, and biopolymers. The strain characterized as of Brevibacterium avium presented cellulase and amylase activities up to 4 M NaCl and also produced EPSs and PHAs. These results indicate the biotechnological potential of certain microorganisms recovered from the composting process, including halotolerant species, which have the ability to produce enzymes and biopolymers, offering new perspectives for environmental and industrial applications.


Subject(s)
Bacillus/isolation & purification , Biological Products/analysis , Brevibacterium/isolation & purification , Hydrolases/analysis , Soil Microbiology , Sodium Chloride/metabolism , Staphylococcus/isolation & purification , Brazil , Bacillus/classification , Bacillus/genetics , Bacillus/metabolism , Brevibacterium/classification , Brevibacterium/genetics , Brevibacterium/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Soil , Staphylococcus/classification , Staphylococcus/genetics , Staphylococcus/metabolism
15.
Braz. j. microbiol ; 46(2): 397-406, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749738

ABSTRACT

Penicillum janthinellum SDX7 was isolated from aged petroleum hydrocarbon-affected soil at the site of Anand, Gujarat, India, and was tested for different pH, temperature, agitation and concentrations for optimal growth of the isolate that was capable of degrading upto 95%, 63% and 58% of 1%, 3% and 5% kerosene, respectively, after a period of 16 days, at optimal growth conditions of pH 6.0, 30 °C and 180 rpm agitation. The GC/MS chromatograms revealed that then-alkane fractions are easily degraded; however, the rate might be lower for branched alkanes, n-alkylaromatics, cyclic alkanes and polynuclear aromatics. The test doses caused a concentration-dependent depletion of carbohydrates of P. janthinellum SDX7 by 3% to 80%, proteins by 4% to 81% and amino acids by 8% to 95% upto 16 days of treatment. The optimal concentration of 3% kerosene resulted in the least reduction of the metabolites of P. janthinellum such as carbohydrates, proteins and amino acids with optimal growth compared to 5% and 1% (v/v) kerosene doses on the 12th and 16th day of exposure. Phenols were found to be mounted by 43% to 66% at lower and higher concentrations during the experimental period. Fungal isolate P. janthinellum SDX7 was also tested for growth on various xenobiotic compounds.


Subject(s)
Kerosene , Penicillium/growth & development , Penicillium/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Xenobiotics/metabolism , Base Composition , Biotransformation , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Gas Chromatography-Mass Spectrometry , Genes, rRNA , Hydrogen-Ion Concentration , India , Molecular Sequence Data , Penicillium/genetics , Penicillium/isolation & purification , RNA, Fungal/genetics , /genetics , Sequence Analysis, DNA , Temperature
16.
Braz. j. microbiol ; 46(2): 455-464, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749744

ABSTRACT

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10−4 mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.


Subject(s)
Bacillus/isolation & purification , Calcium Carbonate/metabolism , Caulobacteraceae/isolation & purification , Geologic Sediments/microbiology , Sporosarcina/isolation & purification , Ammonium Compounds/metabolism , Bacillus/classification , Bacillus/genetics , Bacillus/metabolism , Cluster Analysis , Caulobacteraceae/classification , Caulobacteraceae/genetics , Caulobacteraceae/metabolism , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Sporosarcina/classification , Sporosarcina/genetics , Sporosarcina/metabolism , Urea/metabolism , X-Ray Diffraction
17.
Braz. j. microbiol ; 46(1): 29-39, 05/2015. tab, graf
Article in English | LILACS | ID: lil-748236

ABSTRACT

Awareness on antioxidants and its significance in human healthcare has increased many folds in recent time. Increased demand requisite on welcoming newer and alternative resources for natural antioxidants. Seaweed associated pigmented bacteria screened for its antioxidant potentials reveals 55.5% of the organisms were able to synthesize antioxidant compounds. DPPH assay showed 20% of the organisms to reach a antioxidant zone of 1 cm and 8.3% of the strains more than 3 cm. Pseudomonas koreensis (JX915782) a Sargassum associated yellowish brown pigmented bacteria have better activity than known commercial antioxidant butylated hydroxytoluene (BHT) against DPPH scavenging. Serratia rubidaea (JX915783), an associate of Ulva sp. and Pseudomonas argentinensis (JX915781) an epiphyte of Chaetomorpha media, were also contributed significantly towards ABTS (7.2% ± 0.03 to 15.2 ± 0.09%; 1.8% ± 0.01 to 15.7 ± 0.22%) and FRAP (1.81 ± 0.01 to 9.35 ± 0.98; 7.97 ± 0.12 to 18.70 ± 1.84 μg/mL of AsA Eq.) respectively. 16S rRNA gene sequence analysis revealed bacteria that have higher antioxidant activity belongs to a bacterial class Gammaproteobacteria. Statistical analysis of phenolic contents in relation with other parameters like DPPH, ABTS, reducing power and FRAP are well correlated (p < 0.05). Results obtained from the current study inferred that the seaweed associated pigmented bacteria have enormous potential on antioxidant compounds and need to be extracted in a larger way for clinical applications.


Subject(s)
Antioxidants/metabolism , Aquatic Organisms/classification , Aquatic Organisms/metabolism , Gammaproteobacteria/classification , Gammaproteobacteria/metabolism , Seaweed/microbiology , Aquatic Organisms/genetics , Aquatic Organisms/isolation & purification , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Gammaproteobacteria/genetics , Gammaproteobacteria/isolation & purification , Molecular Sequence Data , Pigments, Biological/metabolism , /genetics , Sequence Analysis, DNA
18.
Article in English | WPRIM | ID: wpr-212739

ABSTRACT

Blastocystis sp. is a common zoonotic intestinal protozoa which has been classified into 17 subtypes (STs). A cross-sectional study was conducted to determine the prevalence and subtype distribution of Blastocystis in villagers living on the Thai-Myanmar border, where the risk of parasitic infection is high. A total of 207 stool samples were collected and DNA was extracted. PCR and sequencing using primers targeting small-subunit ribosomal RNA (SSU rRNA) gene were performed. The prevalence of Blastocystis infection was 37.2% (77/207). ST3 (19.8%; 41/207) was the predominant subtype, followed by ST1 (11.6%; 24/207), ST2 (5.3%; 11/207), and ST4 (0.5%; 1/207). A phylogenetic tree was reconstructed using the maximum likelihood (ML) method based on the Hasegawa-Kishino-Yano + G + I model. The percentage of bootstrapped trees in which the associated taxa clustered together was relatively high. Some sequences of Blastocystis positive samples (TK18, 39, 46, 71, and 90) were closely related to animals (pig and cattle) indicating zoonotic risks. Therefore, proper health education in parasitic prevention for the villagers should be promoted to improve their personal hygiene. Further longitudinal studies are required to monitor the prevalence of parasitic infections after providing health education and to investigate Blastocystis ST in animals living in these villages.


Subject(s)
Adult , Aged , Animals , Blastocystis/classification , Blastocystis Infections/parasitology , Cluster Analysis , Cross-Sectional Studies , DNA, Protozoan/chemistry , DNA, Ribosomal/chemistry , Female , Humans , Male , Middle Aged , Myanmar , Phylogeny , RNA, Ribosomal, 18S/genetics , Rural Population , Sequence Analysis, DNA , Seroepidemiologic Studies , Serogroup , Thailand , Young Adult
19.
Article in English | WPRIM | ID: wpr-180021

ABSTRACT

The objective of this study was to investigate the prevalence of tick-borne pathogens in the Korean water deer (Hydropotes inermis argyropus). Pathogens were identified using PCR which included Anaplasma, Ehrlichia, Rickettsia, and Theileria. Rickettsia was not detected, whereas Anaplasma, Ehrlichia, and Theileria infections were detected in 4, 2, and 8 animals, respectively. The most prevalent pathogen was Theileria. Of the 8 Theileria-positive animals, 2 were mixed-infected with 3 pathogens (Anaplasma, Ehrlichia, and Theileria) and another 2 animals showed mixed-infection with 2 pathogens (Anaplasma and Theileria). Sequencing analysis was used to verify the PCR results. The pathogens found in this study were identified as Anaplasma phagocytophilum, Ehrlichia canis, and Theileria sp. To the best of our knowledge, this is the first report identifying these 3 pathogens in the Korean water deer. Our results suggest that the Korean water deer may serve as a major reservoir for these tick-borne pathogens, leading to spread of tick-borne diseases to domestic animals, livestock, and humans. Further studies are needed to investigate their roles in this respect.


Subject(s)
Anaplasma/isolation & purification , Animals , Bacterial Infections/epidemiology , Cluster Analysis , Coinfection/epidemiology , DNA, Bacterial/chemistry , DNA, Ribosomal/chemistry , Ehrlichia/isolation & purification , Korea/epidemiology , Molecular Sequence Data , Phylogeny , Prevalence , RNA, Ribosomal, 16S/genetics , Rickettsia/isolation & purification , Ruminants/microbiology , Sequence Analysis, DNA , Theileria/isolation & purification
20.
Article in English | WPRIM | ID: wpr-130558

ABSTRACT

Strongyloides stercoralis can cause systemic infection, termed strongyloidiasis, and gastrointestinal ulcer disease in immunocompromised patients. However, to our knowledge, there are no reported cases of comorbid gastric adenocarcinoma and S. stercoralis infection. Here, we report a case of an 81-year-old Korean man who presented with S. stercoralis infection coexisting with early gastric adenocarcinoma (T1aN0M0). S. stercoralis eggs, rhabditiform larvae, and adult females were observed in normal gastric and duodenal crypts. They were also observed in atypical glands representative of adenocarcinoma and adenoma. Preliminary laboratory tests revealed mild neutrophilic and eosinophilic leukocytosis. A routine stool test failed to detect rhabditiform larvae in the patient's fecal sample; however, S. stercoralis was identified by PCR amplification and 18S rRNA sequencing using genomic DNA extracted from formalin-fixed paraffin-embedded tissues. Postoperatively, the patient had a persistent fever and was treated with albendazole for 7 days, which alleviated the fever. The patient was followed-up by monitoring and laboratory testing for 4 months postoperatively, and no abnormalities were observed thus far. The fact that S. stercoralis infection may be fatal in immunocompromised patients should be kept in mind when assessing high-risk patients.


Subject(s)
Adenocarcinoma/complications , Aged, 80 and over , Albendazole/therapeutic use , Animals , Anthelmintics/therapeutic use , DNA, Helminth/chemistry , DNA, Ribosomal/chemistry , Endoscopy, Digestive System , Female , Histocytochemistry , Humans , Korea , Male , RNA, Ribosomal, 18S/genetics , Sequence Analysis, DNA , Stomach Neoplasms/complications , Strongyloides stercoralis/isolation & purification , Strongyloidiasis/complications , Treatment Outcome
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