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1.
Braz. arch. biol. technol ; 64: e21190020, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153295

ABSTRACT

HIGHLIGHTS Screening extremophile Bacillus strains from various Hot Springs Characterization Of Bacillus Strains Producing Highly Thermostable Amylase Genetic identification of the best strains


Abstract Currently thermostable Amylase represents a broad biotechnological interest and desired by a various industries. In this study, forty-six bacterial strains belonging to the genus Bacillus were isolated from various hot springs in the North West of Algeria based on their ability to degrade starch and produce amylase in Starch Agar medium. The majority of isolates showed a positive amylolytic activity. In order to select the most thermostables amylase the effect of temperature on enzymes was estimated, therefore the study of amylase thermostability was culminated by the selection of Four Strains having an interesting optimum of activity and range of stability, reaching 75 °C for the strains HBH1-2, HBH1-3, HBH3-1and 85 °C for the strain HC-2, This indicates that the Enzyme produced by retained strains have optimum activity at high temperature. The identity of the selected strains was established on the basis of the morphological, biochemical characteristics and phylogenetic position as determined by 16S Ribosomal DNA gene sequencing. The whole strains belonged to the genus Bacillus and their phylogeny were also reported in this study.


Subject(s)
Bacillus/isolation & purification , Bacillus/classification , Hot Springs/microbiology , Amylases , Phylogeny , Bacillus/genetics , RNA, Ribosomal, 16S , Algeria , Hot Temperature
2.
Braz. j. microbiol ; 49(1): 54-59, Jan.-Mar. 2018. tab
Article in English | LILACS | ID: biblio-889195

ABSTRACT

ABSTRACT Plant Growth Promoting Rhizobacteria (PGPR) have different mechanisms of action in the development of plants, such as growth promotion, production of phytohormones and antibiotic substances and changes in root exudates. These help to control plant diseases. In order to evaluate the potential of microorganisms in the control of Meloidogyne javanica and Ditylenchus spp., five rhizobacteria isolated from rhizosphere of garlic cultivated in the Curitibanos (SC) region were tested. Hatching chambers were set on Petri dishes, in which were added 10 mL of bacterial suspension and 1 mL of M. javanica eggs suspension, at the rate of 4500, on the filter paper of each chamber. The same procedure was performed with 300 juvenile Ditylenchus spp. The experimental design was completely randomized, with four replications. The evaluations were performed every 72 h for nine days. The antagonized population of nematodes was determined in Peters counting chamber, determining the percentage hatching (for M. javanica) and motility (for Ditylenchus spp). Isolates CBSAL02 and CBSAL05 significantly reduced the hatching of M. javanica eggs (74% and 54.77%, respectively) and the motility of Ditylenchus spp. (55.19% and 53.53%, respectively) in vitro. Isolates were identified as belonging to the genera Pseudomonas (CBSAL05) and Bacillus (CBSAL02).


Subject(s)
Animals , Bacillus/physiology , Plant Diseases/prevention & control , Pseudomonas/physiology , Tylenchoidea/microbiology , Bacillus/genetics , Bacillus/isolation & purification , Pest Control, Biological , Plant Diseases/parasitology , Pseudomonas/genetics , Pseudomonas/isolation & purification , Tylenchoidea/physiology
3.
Braz. j. microbiol ; 49(supl.1): 40-46, 2018. tab
Article in English | LILACS | ID: biblio-974339

ABSTRACT

Abstract Bacterial endophytes are considered to have a beneficial effect on host plants, improving their growth by different mechanisms. The objective of this study was to investigate the capacity of four endophytic Bacillus strains to solubilize iron phosphate (Fe-P), produce siderophores and indole-acetic acid (IAA) in vitro, and to evaluate their plant growth promotion ability in greenhouse conditions by inoculation into pearl millet cultivated in a P-deficient soils without P fertilization, with Araxá rock phosphate or soluble triple superphosphate. All strains solubilized Fe-P and three of them produced carboxylate-type siderophores and high levels of IAA in the presence of tryptophan. Positive effect of inoculation of some of these strains on shoot and root dry weight and the N P K content of plants cultivated in soil with no P fertilization might result from the synergistic combination of multiple plant growth promoting (PGP) traits. Specifically, while B1923 enhanced shoot and root dry weight and root N P content of plants cultivated with no P added, B2084 and B2088 strains showed positive performance on biomass production and accumulation of N P K in the shoot, indicating that they have higher potential to be microbial biofertilizer candidates for commercial applications in the absence of fertilization.


Subject(s)
Bacillus/metabolism , Food/metabolism , Pennisetum/growth & development , Pennisetum/microbiology , Endophytes/metabolism , Indoleacetic Acids/metabolism , Phosphates/analysis , Phosphates/metabolism , Bacillus/genetics , Siderophores/metabolism , Plant Roots/growth & development , Plant Roots/metabolism , Plant Roots/microbiology , Pennisetum/metabolism , Endophytes/genetics , Iron/metabolism
4.
Braz. j. microbiol ; 48(4): 656-670, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-889178

ABSTRACT

ABSTRACT This study aimed to explore the effects of two siderophore-producing bacterial strains on iron absorption and plant growth of peanut in calcareous soil. Two siderophore-producing bacterial strains, namely, YZ29 and DZ13, isolated from the rhizosphere soil of peanut, were identified as Paenibacillus illinoisensis and Bacillus sp., respectively. In potted experiments, YZ29 and DZ13 enhanced root activity, chlorophyll and active iron content in leaves, total nitrogen, phosphorus and potassium accumulation of plants and increased the quality of peanut kernels and plant biomass over control. In the field trial, the inoculated treatments performed better than the controls, and the pod yields of the three treatments inoculated with YZ29, DZ13, and YZ29 + DZ13 (1:1) increased by 37.05%, 13.80% and 13.57%, respectively, compared with the control. Based on terminal restriction fragment length polymorphism analysis, YZ29 and DZ13 improved the bacterial community richness and species diversity of soil surrounding the peanut roots. Therefore, YZ29 and DZ13 can be used as candidate bacterial strains to relieve chlorosis of peanut and promote peanut growth. The present study is the first to explore the effect of siderophores produced by P. illinoisensis on iron absorption.


Subject(s)
Arachis/growth & development , Arachis/microbiology , Bacillus/metabolism , Paenibacillus/metabolism , Iron/metabolism , Arachis/metabolism , Arachis/chemistry , Seeds/growth & development , Seeds/metabolism , Seeds/microbiology , Seeds/chemistry , Soil/chemistry , Soil Microbiology , Bacillus/isolation & purification , Bacillus/classification , Bacillus/genetics , Biological Transport , Siderophores/metabolism , Plant Roots/microbiology , Paenibacillus/isolation & purification , Paenibacillus/classification , Paenibacillus/genetics , Rhizosphere , Agricultural Inoculants/metabolism
5.
Braz. j. microbiol ; 48(3): 451-460, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-889134

ABSTRACT

Abstract This study was focused on the polyhydroxybutyrate (PHB) accumulation property of Bacillus aryabhattai isolated from environment. Twenty-four polyhydroxyalkanoate (PHA) producers were screened out from sixty-two environmental bacterial isolates based on Sudan Black B colony staining. Based on their PHA accumulation property, six promising isolates were further screened out. The most productive isolate PHB10 was identified as B. aryabhattai PHB10. The polymer production maxima were 3.264 g/L, 2.181 g/L, 1.47 g/L, 1.742 g/L and 1.786 g/L in glucose, fructose, maltose, starch and glycerol respectively. The bacterial culture reached its stationary and declining phases at 18 h and 21 h respectively and indicated growth-associated PHB production. Nuclear Magnetic Resonance (NMR) spectra confirmed the material as PHB. The material has thermal stability between 30 and 140 °C, melting point at 170 °C and maximum thermal degradation at 287 °C. The molecular weight and poly dispersion index of the polymer were found as 199.7 kDa and 2.67 respectively. The bacterium B. aryabhattai accumulating PHB up to 75% of cell dry mass utilizing various carbon sources is a potential candidate for large scale production of bacterial polyhydroxybutyrate.


Subject(s)
Bacillus/metabolism , Polyhydroxyalkanoates/biosynthesis , Starch/metabolism , Bacillus/isolation & purification , Bacillus/growth & development , Bacillus/genetics , Culture Media/metabolism , Culture Media/chemistry , Environmental Microbiology , Polyhydroxyalkanoates/chemistry , Glycerol/metabolism
6.
Braz. j. microbiol ; 47(4): 931-940, Oct.-Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-828205

ABSTRACT

Abstract Twelve bacterial strains isolated from shrimp farming ponds were screened for their growth activity on chitin as the sole carbon source. The highly chitinolytic bacterial strain was detected by qualitative cup plate assay and tentatively identified to be Cohnella sp. A01 based on 16S rDNA sequencing and by matching the key morphological, physiological, and biochemical characteristics. The cultivation of Cohnella sp. A01 in the suitable liquid medium resulted in the production of high levels of enzyme. The colloidal chitin, peptone, and K2HPO4 represented the best carbon, nitrogen, and phosphorus sources, respectively. Enzyme production by Cohnella sp. A01 was optimized by the Taguchi method. Our results demonstrated that inoculation amount and temperature of incubation were the most significant factors influencing chitinase production. From the tested values, the best pH/temperature was obtained at pH 5 and 70 °C, with Km and V max values of chitinase to be 5.6 mg/mL and 0.87 µmol/min, respectively. Ag+, Co2+, iodoacetamide, and iodoacetic acid inhibited the enzyme activity, whereas Mn2+, Cu2+, Tweens (20 and 80), Triton X-100, and EDTA increased the same. In addition, the study of the morphological alteration of chitin treated by enzyme by SEM revealed cracks and pores on the chitin surface, indicating a potential application of this enzyme in several industries.


Subject(s)
Bacillus/metabolism , Chitinases/metabolism , Phosphorus/metabolism , Temperature , Bacillus/isolation & purification , Bacillus/genetics , Bacillus/ultrastructure , Enzyme Stability/drug effects , Carbon/metabolism , RNA, Ribosomal, 16S/genetics , Kinetics , Chitinases/chemistry , Sequence Analysis, DNA , Enzyme Activation , Hydrogen-Ion Concentration , Ions , Metals , Nitrogen/metabolism
7.
Braz. j. microbiol ; 46(4): 977-989, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769669

ABSTRACT

Abstract A total of 48 endophytic bacteria were isolated from surface-sterilized tissues of the medicinal plant Lonicera japonica, which is grown in eastern China; six strains were selected for further study based on their potential ability to promote plant growth in vitro (siderophore and indoleacetic acid production). The bacteria were characterized by phylogenetically analyzing their 16S rRNA gene similarity, by examining their effect on the mycelial development of pathogenic fungi, by testing their potential plant growth-promoting characteristics, and by measuring wheat growth parameters after inoculation. Results showed that the number of endophytic bacteria in L. japonica varied among different tissues, but it remained relatively stable in the same tissues from four different plantation locations. Among the three endophytic strains, strains 122 and 124 both had high siderophore production, with the latter showing the highest phosphate solubilization activity (45.6 mg/L) and aminocyclopropane-1-carboxylic acid deaminase activity (47.3 nmol/mg/h). Strain 170 had the highest indoleacetic acid (IAA) production (49.2 mg/L) and cellulase and pectinase activities. After inoculation, most of the six selected isolates showed a strong capacity to promote wheat growth. Compared with the controls, the increase in the shoot length, root length, fresh weight, dry weight, and chlorophyll content was most remarkable in wheat seedlings inoculated with strain 130. The positive correlation between enzyme (cellulose and pectinase) activity and inhibition rate on Fusarium oxysporum, the IAA production, and the root length of wheat seedlings inoculated with each tested endophytic strain was significant in regression analysis. Deformity of pathogenic fungal mycelia was observed under a microscope after the interaction with the endophytic isolates. Such deformity may be directly related to the production of hydrolytic bacterial enzymes (cellulose and pectinase). The six endophytic bacterial strains were identified to be Paenibacillus and Bacillus strains based on the results of 16S rRNA gene sequencing analysis and their physiological and biochemical characteristics. Results indicate the promising application of endophytic bacteria to the biological control of pathogenic fungi and the improvement of wheat crop growth.


Subject(s)
Bacillus/classification , Bacillus/genetics , Bacillus/growth & development , Bacillus/isolation & purification , Bacillus/metabolism , Bacillus/microbiology , China/classification , China/genetics , China/growth & development , China/isolation & purification , China/metabolism , China/microbiology , Endophytes/classification , Endophytes/genetics , Endophytes/growth & development , Endophytes/isolation & purification , Endophytes/metabolism , Endophytes/microbiology , Indoleacetic Acids/classification , Indoleacetic Acids/genetics , Indoleacetic Acids/growth & development , Indoleacetic Acids/isolation & purification , Indoleacetic Acids/metabolism , Indoleacetic Acids/microbiology , Lonicera/classification , Lonicera/genetics , Lonicera/growth & development , Lonicera/isolation & purification , Lonicera/metabolism , Lonicera/microbiology , Molecular Sequence Data/classification , Molecular Sequence Data/genetics , Molecular Sequence Data/growth & development , Molecular Sequence Data/isolation & purification , Molecular Sequence Data/metabolism , Molecular Sequence Data/microbiology , Paenibacillus/classification , Paenibacillus/genetics , Paenibacillus/growth & development , Paenibacillus/isolation & purification , Paenibacillus/metabolism , Paenibacillus/microbiology , Phylogeny/classification , Phylogeny/genetics , Phylogeny/growth & development , Phylogeny/isolation & purification , Phylogeny/metabolism , Phylogeny/microbiology , Plant Roots/classification , Plant Roots/genetics , Plant Roots/growth & development , Plant Roots/isolation & purification , Plant Roots/metabolism , Plant Roots/microbiology , Siderophores/classification , Siderophores/genetics , Siderophores/growth & development , Siderophores/isolation & purification , Siderophores/metabolism , Siderophores/microbiology , Triticum/classification , Triticum/genetics , Triticum/growth & development , Triticum/isolation & purification , Triticum/metabolism , Triticum/microbiology
8.
Braz. j. microbiol ; 46(4): 1065-1076, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769637

ABSTRACT

Abstract Thermophilic 32 isolates and 20 reference bacilli were subjected to Rep-PCR and ITS-PCR fingerprinting for determination of their genotypic diversity, before screening lipase activities. By these methods, all the isolates and references could easily be differentiated up to subspecies level from each other. In screening assay, 11 isolates and 7 references were found to be lipase producing. Their extracellular lipase activities were measured quantitatively by incubating in both tributyrin and olive oil broths at 60 °C and pH 7.0. During the 24, 48 and 72-h period of incubation, the changes in the lipase activities, culture absorbance, wet weight of biomass and pH were all measured. The activity was determined by using pNPB in 50 mM phosphate buffer at pH 7.0 at 60 °C. The lipase production of the isolates in olive oil broths varied between 0.008 and 0.052, whereas these values were found to be 0.002-0.019 (U/mL) in the case of tyributyrin. For comparison, an index was established by dividing the lipase activities to cell biomass (U/mg). The maximum thermostable lipase production was achieved by the isolates F84a, F84b, and G. thermodenitrificans DSM 465T (0.009, 0.008 and 0.008 U/mg) within olive oil broth, whereas G. stearothermophilus A113 displayed the highest lipase activity than its type strain in tyributyrin. Therefore, as some of these isolates displayed higher activities in comparison to references, new lipase producing bacilli were determined by presenting their genotypic diversity with DNA fingerprinting techniques.


Subject(s)
Bacillus/chemistry , Bacillus/classification , Bacillus/enzymology , Bacillus/genetics , Bacillus/growth & development , Bacillus/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/classification , Bacterial Proteins/enzymology , Bacterial Proteins/genetics , Bacterial Proteins/growth & development , Bacterial Proteins/metabolism , Enzyme Stability/chemistry , Enzyme Stability/classification , Enzyme Stability/enzymology , Enzyme Stability/genetics , Enzyme Stability/growth & development , Enzyme Stability/metabolism , Genetic Variation/chemistry , Genetic Variation/classification , Genetic Variation/enzymology , Genetic Variation/genetics , Genetic Variation/growth & development , Genetic Variation/metabolism , Genotype/chemistry , Genotype/classification , Genotype/enzymology , Genotype/genetics , Genotype/growth & development , Genotype/metabolism , Hot Temperature/chemistry , Hot Temperature/classification , Hot Temperature/enzymology , Hot Temperature/genetics , Hot Temperature/growth & development , Hot Temperature/metabolism , Hydrogen-Ion Concentration/chemistry , Hydrogen-Ion Concentration/classification , Hydrogen-Ion Concentration/enzymology , Hydrogen-Ion Concentration/genetics , Hydrogen-Ion Concentration/growth & development , Hydrogen-Ion Concentration/metabolism , Lipase/chemistry , Lipase/classification , Lipase/enzymology , Lipase/genetics , Lipase/growth & development , Lipase/metabolism , Phylogeny/chemistry , Phylogeny/classification , Phylogeny/enzymology , Phylogeny/genetics , Phylogeny/growth & development , Phylogeny/metabolism
9.
Braz. j. microbiol ; 46(4): 1111-1118, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769642

ABSTRACT

Abstract In the present work, twelve bacilli were isolated from four different regions of human skin from Bela population of Nagpur district, India. The isolated bacilli were identified by their morphological, cultural and biochemical characteristics. Seven isolates were Gram negative rods, out of which five were belong to genus Pseudomonas. Three among the five Gram positive isolates were identified as Dermabactor and the remaining two Bacillus. Their antimicrobial susceptibility profile was determined by Kirby-Bauer disc diffusion method. The isolates showed resistance to several currently used broad-spectrum antibiotics. The Dermabactor genus was resistant to vancomycin, although it was earlier reported to be susceptible. Imipenem was found to be the most effective antibiotic for Pseudomonas while nalidixic acid, ampicillin and tetracycline were ineffective. Isolates of Bacillus displayed resistance to the extended spectrum antibiotics cephalosporin and ceftazidime. Imipenem, carbenicillin and ticarcillin were found to be the most effective antibiotics as all the investigated isolates were susceptible to them. Antibiotic resistance may be due to the overuse or misuse of antibiotics during the treatment, or following constant exposure to antibiotic-containing cosmetic formulations.


Subject(s)
Adolescent/classification , Adolescent/drug effects , Adolescent/genetics , Adolescent/isolation & purification , Adolescent/microbiology , Adolescent/pharmacology , Adult/classification , Adult/drug effects , Adult/genetics , Adult/isolation & purification , Adult/microbiology , Adult/pharmacology , Anti-Bacterial Agents/classification , Anti-Bacterial Agents/drug effects , Anti-Bacterial Agents/genetics , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/microbiology , Anti-Bacterial Agents/pharmacology , Bacillus/classification , Bacillus/drug effects , Bacillus/genetics , Bacillus/isolation & purification , Bacillus/microbiology , Bacillus/pharmacology , Female/classification , Female/drug effects , Female/genetics , Female/isolation & purification , Female/microbiology , Female/pharmacology , Healthy Volunteers/classification , Healthy Volunteers/drug effects , Healthy Volunteers/genetics , Healthy Volunteers/isolation & purification , Healthy Volunteers/microbiology , Healthy Volunteers/pharmacology , Humans/classification , Humans/drug effects , Humans/genetics , Humans/isolation & purification , Humans/microbiology , Humans/pharmacology , Male/classification , Male/drug effects , Male/genetics , Male/isolation & purification , Male/microbiology , Male/pharmacology , Microbial Sensitivity Tests/classification , Microbial Sensitivity Tests/drug effects , Microbial Sensitivity Tests/genetics , Microbial Sensitivity Tests/isolation & purification , Microbial Sensitivity Tests/microbiology , Microbial Sensitivity Tests/pharmacology , Middle Aged/classification , Middle Aged/drug effects , Middle Aged/genetics , Middle Aged/isolation & purification , Middle Aged/microbiology , Middle Aged/pharmacology , Skin/classification , Skin/drug effects , Skin/genetics , Skin/isolation & purification , Skin/microbiology , Skin/pharmacology , Young Adult/classification , Young Adult/drug effects , Young Adult/genetics , Young Adult/isolation & purification , Young Adult/microbiology , Young Adult/pharmacology
10.
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
11.
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
12.
Indian J Exp Biol ; 2014 Jul; 52(7): 739-747
Article in English | IMSEAR | ID: sea-153754

ABSTRACT

Mosquitocidal bacteria are environmentally friendly alternatives to chemical insecticides for controlling mosquitoes and therefore, there have been tremendous world-wide efforts to identify novel mosquitocidal bacteria from natural environment. In the present study, excreta from arid-birds were analyzed for identifying mosquitocidal bacteria. The selection of sample for bacterial screening is significant, because, arid-birds are the unique living species and gathering the foods from variety of sources from environment. Out of 1000 samples examined, twelve bacterial strains were identified as mosquitocidal and the 16S rRNA gene sequence alignment depicted that these isolates belonged to Bacillus species (Bacillus thuringiensis, B.sphaericus and B.cereus). Toxicity assay against mosquito vectors have shown that these isolates are potential. The B. sphaericus VCRC-B547 (NCBI: JN377789) has shown a higher toxicity against Cx. quinquefasciatus, An. stephensi, and Aed. aegypti. Result from SDS-PAGE has shown that there was considerable difference in the protein profiles among the new bacterial isolates. Phylogenetic tree with branch length 0.05 revealed three distinct groups with homology among the closely related Bacillus strains. This study therefore throws considerable interest on the diversity of microbial organisms from arid birds and its application in mosquito control.


Subject(s)
Animals , Bacillus/classification , Bacillus/genetics , Bacillus/isolation & purification , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Toxins/toxicity , Birds/parasitology , Culicidae/drug effects , Culicidae/parasitology , DNA, Bacterial/genetics , Electrophoresis, Polyacrylamide Gel , Feces/parasitology , Larva/parasitology , Mosquito Control/methods , Phylogeny , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics
13.
Braz. j. microbiol ; 45(2): 389-393, Apr.-June 2014. ilus
Article in English | LILACS | ID: lil-723093

ABSTRACT

Proteolysis-resistant lipases can be well exploited by industrial processes which employ both lipase and protease as biocatalysts. A proteolysis resistant lipase from Bacillus pumilus SG2 was isolated, purified and characterized earlier. The lipase was resistant to native and commercial proteases. In the present work, we have characterized the lip gene which encodes the proteolysis-resistant lipase from Bacillus pumilus SG2. The parameters and structural details of lipase were analysed. The lip gene consisted of 650 bp. The experimental molecular weight of SG2 lipase was nearly double that of its theoretical molecular weight, thus suggesting the existence of the functional lipase as a covalent dimer. The proteolytic cleavage sites of the lipase would have been made inaccessible by dimerisation, thus rendering the lipase resistant to protease.


Subject(s)
Bacillus/enzymology , Bacillus/genetics , Lipase/genetics , Lipase/metabolism , Amino Acid Sequence , Base Sequence , Lipase/chemistry , Molecular Sequence Data , Molecular Weight , Phylogeny , Protein Multimerization , Proteolysis , Peptide Hydrolases/metabolism , Sequence Homology
14.
Braz. j. microbiol ; 45(2): 621-625, Apr.-June 2014. ilus, tab
Article in English | LILACS | ID: lil-723126

ABSTRACT

Eight endophytic isolates assigned to Pseudomonas, Azospirillum, and Bacillus genera according to pheno-genotypic features were retrieved from barley seeds under selective pressure for nitrogen-fixers. Genetic relationships among related isolates were investigated through RAPD. Six isolates displayed nitrogen-fixing ability, while all could biosynthesize indolacetic acid in vitro and showed no antibiosis effects against Azospirillum brasilense Az39, a recognized PGPR.


Subject(s)
Azospirillum brasilense/isolation & purification , Bacillus/isolation & purification , Endophytes/isolation & purification , Hordeum/microbiology , Nitrogen Fixation , Pseudomonas/isolation & purification , Seeds/microbiology , Antibiosis , Azospirillum brasilense/classification , Azospirillum brasilense/genetics , Azospirillum brasilense/metabolism , Bacillus/classification , Bacillus/genetics , Bacillus/metabolism , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Endophytes/classification , Endophytes/genetics , Endophytes/metabolism , Indoleacetic Acids/metabolism , Molecular Typing , Pseudomonas/classification , Pseudomonas/genetics , Pseudomonas/metabolism , Random Amplified Polymorphic DNA Technique , /genetics , Sequence Analysis, DNA
15.
Braz. j. microbiol ; 43(2): 606-617, Apr.-June 2012. graf, tab
Article in English | LILACS | ID: lil-644477

ABSTRACT

Pyrene, a high molecular weight polycyclic aromatic hydrocarbon (PAH), is a priority pollutant present in soil contaminated with crude oil, coal-tar and complex PAHs. Bacterial consortium CON-3 developed from crude oil contaminated soil of Patiala, Punjab (India) cometabolized 50 µg ml-1 pyrene in the presence of glucose (0.5 %; w/v) at 30 °C, as determined by reverse-phase high performance liquid chromatography (HPLC). Bacillus sp. PK-12, Bacillus sp. PK-13 and Bacillus sp. PK-14 from CON-3, identified by 16S rRNA gene sequence analysis, were able to cometabolize 64 %, 55 % and 53 % of pyrene in 35 days, respectively. With the increase in glucose concentration to 1.0 % (w/v) in growth medium isolates PK-12, PK-13 and PK-14 showed 19 - 46 % uptake of 50 µg ml-1 pyrene in 4 days, respectively. Uptake of pyrene was correlated with growth and biosurfactant activity, which is suggestive of the potential role of members of Bacillus genera in pyrene mobilization and its uptake.


Subject(s)
Bacillus/genetics , Bacillus/isolation & purification , Environmental Pollution , In Vitro Techniques , Petroleum/analysis , Pyrenes/analysis , Pyrenes/isolation & purification , Sequence Analysis, DNA , Chromatography, High Pressure Liquid , Methods , Soil
16.
Article in English | WPRIM | ID: wpr-89103

ABSTRACT

BACKGROUND: The aims of this study were to compare several DNA extraction methods and 16S rDNA primers and to evaluate the clinical utility of broad-range PCR in continuous ambulatory peritoneal dialysis (CAPD) culture fluids. METHODS: Six type strains were used as model organisms in dilutions from 10(8) to 100 colony-forming units (CFU)/mL for the evaluation of 5 DNA extraction methods and 5 PCR primer pairs. Broad-range PCR was applied to 100 CAPD culture fluids, and the results were compared with conventional culture results. RESULTS: There were some differences between the various DNA extraction methods and primer sets with regard to the detection limits. The InstaGene Matrix (Bio-Rad Laboratories, USA) and Exgene Clinic SV kits (GeneAll Biotechnology Co. Ltd, Korea) seem to have higher sensitivities than the others. The results of broad-range PCR were concordant with the results from culture in 97% of all cases (97/100). Two culture-positive cases that were broad-range PCR-negative were identified as Candida albicans, and 1 PCR-positive but culture-negative sample was identified as Bacillus circulans by sequencing. Two samples among 54 broad-range PCR-positive products could not be sequenced. CONCLUSIONS: There were differences in the analytical sensitivity of various DNA extraction methods and primers for broad-range PCR. The broad-range PCR assay can be used to detect bacterial pathogens in CAPD culture fluid as a supplement to culture methods.


Subject(s)
Bacillus/genetics , Bacteria/genetics , Candida albicans/genetics , DNA Primers/genetics , DNA, Bacterial/analysis , Genetic Techniques/standards , Humans , Peritoneal Dialysis, Continuous Ambulatory , Peritonitis/microbiology , Polymerase Chain Reaction , Reagent Kits, Diagnostic , Sequence Analysis, DNA
17.
Braz. j. microbiol ; 42(1): 66-74, Jan.-Mar. 2011. ilus, tab
Article in English | LILACS | ID: lil-571376

ABSTRACT

Vineyard soils are frequently polluted with high concentrations of copper due application of copper sulfate in order to control fungal diseases. Bioremediation is an efficient process for the treatment of contaminated sites. Efficient copper sorption bacteria can be used for bioremoval of copper from contaminated sites. In this study, a total of 106 copper resistant bacteria were examined for resistance to copper toxicity and biosorption of copper. Eighty isolates (45 from vineyard Mollisol, 35 from Inceptisol) were obtained from EMBRAPA (Empresa Brasileira de Pesquisa Agropecuária) experimental station, Bento Gonçalves, RS, Brazil (29º09'53.92''S and 51º31'39.40''W) and 26 were obtained from copper mining waste from Caçapava do Sul, RS, Brazil (30º29'43.48''S and 53'32'37.87W). Based on resistance to copper toxicity and biosorption, 15 isolates were identified by 16S rRNA gene sequencing. Maximal copper resistance and biosorption at high copper concentration were observed with isolate N2 which removed 80 mg L-1 in 24 h. Contrarily isolate N11 (Bacillus pumilus) displayed the highest specific copper biosorption (121.82 mg/L/OD unit in 24 h). GenBank MEGABLAST analysis revealed that isolate N2 is 99 percent similar to Staphylococcus pasteuri. Results indicate that several of our isolates have potential use for bioremediation treatment of vineyards soils and mining waste contaminated with high copper concentration.


Subject(s)
Mining Acid Water/analysis , Base Sequence , Bacillus/genetics , Bacillus/isolation & purification , Copper/analysis , Copper/toxicity , Garbage , Soil Microbiology , Water Pollution , Water Purification , Biodegradation, Environmental , Methods , Soil , Methods , Toxicity
18.
Pakistan Journal of Pharmaceutical Sciences. 2011; 24 (3): 269-275
in English | IMEMR | ID: emr-129852

ABSTRACT

During screening for antibiotic producing microorganisms from environmental soil samples, the supernatant of a bacterial isolate was found to have antibacterial and antifungal activity on the standard indicator species. The standard cylinder-plate method was used to determine the inhibitory effect of the crude supernatant of each isolate on 6 bacterial and 3 fungal standard strains by measuring the diameter of inhibition zone. The highest inhibition zone on Aspergillus niger belonged to culture broth of isolate FASi by 25 mm, and this isolate was the most efficient microorganism to inhibit standard bacterial and fungal species. Based on morphological and biochemical properties as well as 16S rDNA gene analysis, the selected isolate [isolate FASi] belonged to Bacillus gems. Investigation on the ability of different culture media for antibiotic production led to select Luria-Bertani media for further studies. Treatment of the culture broth of the isolate FAS[1] using typical protease did't decease the antimicrobial activity of the supernatant. After extracting of culture broth of the selected isolate by ethyl acetate as an organic solvent, the inhibitory effect was mainly increased. More investigation was done by bioautography method where the ethyl acetate fraction of the broth culture was separated on TLC by chloroformimethanol, 60:40 as mobile phase and R[f] were calculated for inhibition spots


Subject(s)
Soil Microbiology , Anti-Infective Agents/isolation & purification , Anti-Infective Agents/pharmacology , Culture Media/isolation & purification , Acetates/chemistry , Microbial Sensitivity Tests/methods , RNA, Ribosomal, 16S/genetics , Bacillus/chemistry , Bacillus/genetics
19.
Mem. Inst. Oswaldo Cruz ; 102(8): 919-924, Dec. 2007. ilus
Article in English | LILACS | ID: lil-471856

ABSTRACT

We show for the first time that the ventral diverticulum of the mosquito gut (impermeable sugar storage organ) harbors microorganisms. The gut diverticulum from newly emerged and non-fed Aedes aegypti was dissected under aseptic conditions, homogenized and plated on BHI medium. Microbial isolates were identified by sequencing of 16S rDNA for bacteria and 28S rDNA for yeast. A direct DNA extraction from Ae. aegypti gut diverticulum was also performed. The bacterial isolates were: Bacillus sp., Bacillus subtilis and Serratia sp. The latter was the predominant bacteria found in our isolations. The yeast species identified was Pichia caribbica.


Subject(s)
Animals , Aedes/microbiology , Bacillus/isolation & purification , Gastrointestinal Tract/microbiology , Pichia/isolation & purification , Serratia/isolation & purification , Bacillus/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Pichia/genetics , /genetics , /genetics , Serratia/genetics
20.
Article in English | IMSEAR | ID: sea-24101

ABSTRACT

The role of growth and sporulation in the production of mosquito larvicidal factors in B. sphaericus H-5a5b strains was investigated using 6 strains that differed in their larvicidal activity. Among these, strain B64 produced maximum biomass (15.5 g/l by 29th h) while B45 and B85 yielded the least (12.8 g/l by 41st and 37th h respectively). Strains B43 and B42 reached the peak of viable cell count (4-6 x 10(10) cells/ml) 4 h earlier than B64 and 12 h earlier than the rest of the strains. Strains B42 and B43 produced higher number of heat resistant spores (4 x 10(8) spores/ml), while strains B45 and B57 produced the lowest numbers (2-4 x 10(5) spores/ml). Mosquitocidal toxin synthesis was noticed as early as the 5th and 9th h in the cultures of the strains B42 and B64 respectively while in those of other strains it was detected by the 13th h or later. The results indicated that generally the highly and moderately toxic strains grew faster and sporulated better than the poorly toxic ones.


Subject(s)
Animals , Bacillus/genetics , Culicidae/growth & development , Larva/physiology , Species Specificity , Spores/physiology , Toxins, Biological/metabolism
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