Soil enrichment for the isolation of sporangial subgroup II Bacillus species, and observations concerning a coil-forming member of this group

1972 ◽  
Vol 18 (7) ◽  
pp. 1031-1038
Author(s):  
R. T. Wood ◽  
L. E. Casida Jr.
Keyword(s):  
Ph Value ◽  
Enrichment Culture ◽  
Divalent Cations ◽  
Soil Extract ◽  
Bacillus Species ◽  
Biochemical Tests ◽  
Soil Medium ◽  
Soil Enrichment ◽  
Subgroup Ii ◽  
Characteristic Features

Enrichment culture procedures are described which allow recovery from soil of mainly sporangial subgroup II Bacillus species, subgroup I plus subgroup II, or the latter plus a coil-forming member of subgroup II. After isolation, the coil-forming type grew normally and sporulated extensively only on agarized soil medium. Growth was normal on soil extract agar but sporulation was less extensive. Limited sporulation occurred when divalent cations were added to more conventional media. Normal vegetative growth occurred on other media investigated only when the pH value was held within relatively narrow limits. The presence of carbohydrate in agar media caused partial growth inhibition, a lack of catalase activity, and the formation of very long coiled cells plus pleomorphic cells, whereas overt cell lysis occurred in vigorously shaken broth cultures. These responses possibly reflect an unbalanced growth condition caused by growth at pH extremes, and not by carbohydrate per se. The characteristic features that set the coil-forming bacilli apart from other subgroup II Bacillus species were shown to be (1) their inability to grow at pH values below 6.5, (2) their inability to ferment carbohydrates, (3) their high oxygen requirement for growth, and (4) their ability to reduce thiosulfate to H2S. In addition, these bacilli can be distinguished from closely related established species by other biochemical tests.

Evaluarea impactului ecositemelor urbane asupra mediului în regiunea de dezvoltare economica Centru

2019 ◽  
Author(s):  
Constantin Bulimaga ◽  
◽  
Corina Certan ◽  
Keyword(s):  
Water Pollution ◽  
Surface Water ◽  
Anthropogenic Impact ◽  
Ph Value ◽  
Urban Ecosystems ◽  
Soil Extract ◽  
Specific Character ◽  
Surface Water Pollution

Regardless of the fact that both urban ecosystems studied – Orhei and Telenești – have purification stations, they are still an essential source of surface water pollution. The aqueous soil extract (Telenești) has a pH value of 8 up to 9.8 due to the high content of calcium and potassium in the soil, due to the fact that the area under investigation has a specific character caused by the spread of solonetz-type soils, solonized chernozems, and salinated soils. The anthropogenic impact in urban ecosystems produces an imbalance in the ratio of spontaneous species and ruderal and ruderal-segetal species. The number of spontaneous species is the indicator of the degree of anthropization in urban ecosystems. Urban ecosystems have a major impact on the environment.

Metabolism of carbaryl and carbofuran by soil-enrichment and bacterial cultures

1984 ◽  
Vol 30 (12) ◽  
pp. 1458-1466 ◽  
Author(s):  
B. S. Rajagopal ◽  
V. R. Rao ◽  
G. Nagendrappa ◽  
N. Sethunathan
Keyword(s):  
Enrichment Culture ◽  
Side Chain ◽  
Bacillus Sp ◽  
Mineral Salts ◽  
Prolonged Incubation ◽  
Soil Enrichment ◽  
Enrichment Cultures ◽  
Hydrolysis Products ◽  
Carbamate Insecticides ◽  
Major Route

Metabolism of side chain and ring 14C-labelled carbaryl and carbofuran in a mineral salts medium by soil-enrichment cultures and a Bacillus sp. was studied. A change in the substrate of the medium from carbaryl to carbofuran led to a marked shift in the dominant bacterium from Bacillus sp. to Arthrobacter sp. although carbaryl-enrichment culture was the primary inoculum in both media. Hydrolysis was the major route of microbial degradation of both carbamate insecticides. During carbaryl degradation by enrichment cultures and Bacillus sp., 1-naphthol and 1,4-naphthoquinone accumulated in the medium. Of the three metabolites formed from carbofuran, 3-hydroxycarbofuran and 3-ketocarbofuran were further metabolized rapidly, while carbofuran phenol was resistant to further degradation. Evolution of 14CO2 and other gaseous 14C-labelled products from both side chain and ring labels was negligible. This and slow degradation of the hydrolysis products led to significant accumulation of 14C in the medium even after prolonged incubation.

scholarly journals The acid deoxyribonuclease of neutrophils: a possible participant in apoptosis-associated genome destruction

Blood ◽  
1995 ◽  
Vol 86 (6) ◽  
pp. 2414-2418 ◽  
Author(s):  
RA Gottlieb ◽  
HA Giesing ◽  
RL Engler ◽  
BM Babior
Keyword(s):  
Dna Cleavage ◽  
Ph Value ◽  
Divalent Cations ◽  
Ph Dependence ◽  
Human Neutrophils ◽  
Ph Optimum ◽  
Differentiated Cells ◽  
Plasmid Nicking Assay ◽  
Plasmid Nicking ◽  
Acid Deoxyribonuclease

Human neutrophils are terminally differentiated cells that spontaneously undergo apoptosis in tissue culture. Apoptosis in these cells can be delayed by culture in the presence of granulocyte colony- stimulating factor or other inflammatory mediators. Neutrophils were found to contain an acid endonuclease that appeared to be responsible for the internucleosomal DNA cleavage that accompanies apoptosis. As measured by a plasmid nicking assay, this endonuclease had a molecular weight (M(r)) of 35,000, a pH optimum of 5.5, and a threshold for activity of pH 6.6 to 6.8. It was weakly inhibited by divalent cations (Ca2+, Mg2+, and Zn2+) and more strongly inhibited by aurintricarboxylic acid and N-bromosuccinimide. DNA from neutrophils treated with nigericin in buffers of defined pH displayed nucleosomal ladders whose prominence varied with pH in a manner that paralleled the pH dependence of the plasmid cleavage assays, consistent with internucleosomal DNA cleavage by the acid endonuclease. We have previously shown that neutrophils undergo acidification to a pH value as low as 6.0 during apoptosis; we suggest that this endonuclease may be responsible for the DNA cleavage seen in apoptotic neutrophils.

scholarly journals Effects of Different Cultivation Parameters on the Production of Surfactin Variants by a Bacillus subtilis Strain

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2675 ◽  
Author(s):  
Attila Bartal ◽  
Aruna Vigneshwari ◽  
Bettina Bóka ◽  
Mónika Vörös ◽  
István Takács ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Metal Ions ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Carbon Sources ◽  
Bacillus Species ◽  
Subtilis Strain ◽  
Fatty Acid Chain ◽  
Characteristic Features ◽  
Surfactin Production

Surfactins are lipopeptide-type biosurfactants produced mainly by Bacillus species, consisting of a peptide loop of seven amino acids and a hydrophobic fatty acid chain (C12–C16). These molecules have been proven to exhibit various biological activities; thus, their therapeutic and environmental applications are considered. Within the surfactin lipopeptide family, there is a wide spectrum of different homologues and isomers; to date, more than 30 variants have been described. Since the newest members of these lipopeptides were described recently, there is no information that is available on their characteristic features, e.g., the dependence of their production from different cultivation parameters. This study examined the effects of both the different carbon sources and various metal ions on the surfactin production of a selected B. subtilis strain. Among the applied carbon sources, fructose and xylose had the highest impacts on the ratio of the different variants, regarding both the peptide sequences and the lengths of the fatty acids. Furthermore, the application of metal ions Mn2+, Cu2+ and Ni2+ in the media completely changed the surfactin variant compositions of the fermenting broths leading to the appearance of methyl esterified surfactin forms, and resulted in the appearance of novel surfactin variants with fatty acid chains containing no more than 11 carbon atoms.

scholarly journals Purification and Characterization of Two Enantioselective α-Ketoglutarate-Dependent Dioxygenases, RdpA and SdpA, from Sphingomonas herbicidovorans MH

2006 ◽  
Vol 72 (7) ◽  
pp. 4853-4861 ◽  
Author(s):  
Tina A. Müller ◽  
Thomas Fleischmann ◽  
Jan Roelof van der Meer ◽  
Hans-Peter E. Kohler
Keyword(s):  
Amino Acids ◽  
Divalent Cations ◽  
Propanoic Acid ◽  
Dichlorophenoxyacetic Acid ◽  
Purification And Characterization ◽  
Subgroup Ii ◽  
2,4 Dichlorophenoxyacetic Acid ◽  
Acid Herbicides ◽  
Growth Experiments

ABSTRACT α-Ketoglutarate-dependent (R)-dichlorprop dioxygenase (RdpA) and α-ketoglutarate-dependent (S)-dichlorprop dioxygenase (SdpA), which are involved in the degradation of phenoxyalkanoic acid herbicides in Sphingomonas herbicidovorans MH, were expressed and purified as His6-tagged fusion proteins from Escherichia coli BL21(DE3)(pLysS). RdpA and SdpA belong to subgroup II of the α-ketoglutarate-dependent dioxygenases and share the specific motif HXDX24TX131HX10R. Amino acids His-111, Asp-113, and His-270 and amino acids His-102, Asp-104, and His 257 comprise the 2-His-1-carboxylate facial triads and were predicted to be involved in iron binding in RdpA and SdpA, respectively. RdpA exclusively transformed the (R) enantiomers of mecoprop [2-(4-chloro-2-methylphenoxy)propanoic acid] and dichlorprop [2-(2,4-dichlorophenoxy)propanoic acid], whereas SdpA was specific for the (S) enantiomers. The apparent Km values were 99 μM for (R)-mecoprop, 164 μM for (R)-dichlorprop, and 3 μM for α-ketoglutarate for RdpA and 132 μM for (S)-mecoprop, 495 μM for (S)-dichlorprop, and 20 μM for α-ketoglutarate for SdpA. Both enzymes had high apparent Km values for oxygen; these values were 159 μM for SdpA and >230 μM for RdpA, whose activity was linearly dependent on oxygen at the concentration range measured. Both enzymes had narrow cosubstrate specificity; only 2-oxoadipate was able to replace α-ketoglutarate, and the rates were substantially diminished. Ferrous iron was necessary for activity of the enzymes, and other divalent cations could not replace it. Although the results of growth experiments suggest that strain MH harbors a specific 2,4-dichlorophenoxyacetic acid-converting enzyme, tfdA-, tfdAα-, or cadAB-like genes were not discovered in a screening analysis in which heterologous hybridization and PCR were used.

scholarly journals SUSCEPTIBILITY PROFILES TO ANTIBIOTICS IN STRAINS OF THE GENUS BACILLUS ISOLATED FROM EXTREME AQUATIC ENVIRONMENTS OF ECUADOR

2021 ◽  
pp. 27-34
Author(s):  
Marco González ◽  
Francisco Viteri ◽  
Luis Villacís ◽  
Jessica Escobar ◽  
Liliana Araujo ◽  
...  
Keyword(s):  
Membrane Filtration ◽  
Sample Volume ◽  
Diffusion Method ◽  
Bacillus Species ◽  
Natural Environments ◽  
Biochemical Tests ◽  
Volcanic Lake ◽  
Antibiotic Resistance Profile ◽  
High Concentrations ◽  
Susceptibility Profiles

Introduction. The water of aquatic ecosystems considered extreme, given the values of its physicochemical and chemical parameters, such as high concentrations of salts, oligotrophic environments, extreme pH, high radiation and extreme temperatures, there is a bacterial population that has adapted to these conditions and that they can be an important reservoir of natural resistomes. Objective. The objective of the present work was to know the profiles of susceptibility to various antibiotics in strains of the Bacillus genus isolated from mineromedicinal water spas and water from a volcanic crater lake in Ecuador. Materials and methods. A total of 16 mineromedicinal water samples and 32 samples of crater volcanic lake water were analyzed. The isolation of the Bacillus colonies was carried out by the membrane filtration technique, using Millipore filters of 0.45 μm pore, a sample volume of 100 mL and R2A agar. The isolated strains were identified following the schemes of MacFaddin (2004), complemented with the biochemical tests of the Microgen galleries for Bacillus. The antibiotic resistance profile was determined by the plate diffusion method of Kirby and Bauer (1966), interpreted according to the CLSI (2019). Results. 19 Bacillus strains were identified. Most of the strains were resistant and multi-resistant to the antibiotic clindamycin, erythromycin, gentamicin, oxacillin, and penicillin. Conclusions. The results indicate the presence of Bacillus species and resistomes associated with this genus in the water of extreme natural environments in Ecuador, which suggests that these environments may be an important reservoir of bacteria resistant to antibiotics.

Characterization of an anaerobic soil enrichment capable of dechlorinating high concentrations of tetrachloroethylene

1997 ◽  
Vol 36 (6-7) ◽  
pp. 117-124 ◽  
Author(s):  
Tae Ho Lee ◽  
Masaharu Yoshimi ◽  
Michihiko Ike ◽  
Masanori Fujita
Keyword(s):  
Yeast Extract ◽  
Enrichment Culture ◽  
Nutritional Requirement ◽  
Soil Enrichment ◽  
Dechlorinating Bacteria ◽  
Potential Alternative ◽  
Curved Rods ◽  
High Concentrations ◽  
Vitamin Mixture

An anaerobic soil enrichment culture could dechlorinate high concentrations of tetrachloroethylene (PCE; 150 mg/liter nominal concentration; approximately 58 mg/liter in aqueous concentration) nearly stoichiometrically to cis-1,2-dichloroethylene (cis-DCE) via trichloroethylene (TCE) at high rates; a maximum dechlorination rate was 0.4 μmol of PCE transformed/mg volatile suspended solids per hr, using citrate as an electron and carbon source and yeast extract as a nutritional requirement. This dechlorinating activity was comparable with those of the previously-reported, efficient bacterial cultures. Some substrates such as pyruvate, succinate, formate, acetate, and acetate with H2 could replace citrate but propionate could not, and yeast extract could be replaced by a vitamin mixture. However the PCE dechlorination rate decreased more than threefold by the addition of the vitamin mixture, suggesting that the vitamin mixture could not be a complete supplement for the nutritional requirement. Optimal pH and temperature of the enrichment for PCE dechlorination were 7 and 30 °C, respectively. Dechlorination of PCE was completely inhibited by the addition of NO3− and NO2− as potential alternative electron acceptors. S2O3−2 and SO3−2 delayed PCE dechlorination but SO4−2 had no significant effect on PCE reduction. 2-bromoethanesulfonic acid (BES, an inhibitor of methanogenesis) also showed no influence on PCE dechlorination, suggesting methanogens were not concerned with PCE removal in this enrichment. Further, microbial investigations on the enrichment showed that it contains four types of bacteria; cocci, large rods, curved rods, and small rods. The small rods seemed to nutritionally support the PCE dechlorinating bacteria, presumably the curved rods.

Stability of nano-sized titanium dioxide in an aqueous environment: effects of pH, dissolved organic matter and divalent cations

2013 ◽  
Vol 68 (2) ◽  
pp. 276-282 ◽  
Author(s):  
X. N. Yang ◽  
F. Y. Cui
Keyword(s):  
Particle Size ◽  
Titanium Dioxide ◽  
Organic Matter ◽  
Zeta Potential ◽  
Dissolved Organic Matter ◽  
Ph Value ◽  
Divalent Cations ◽  
Aqueous Environment ◽  
Nano Tio2 ◽  
The Stability

Nano-sized titanium dioxide in the aquatic environment has a potential impact on the environment and human health. In this study, the impact of pH value, dissolved organic matter (DOM) and divalent cations (Ca2+) on the stability of titanium dioxide nanoparticles (nano-TiO2) in an aqueous environment was investigated in batch tests. The results showed that the particle size of nano-TiO2 was not sensitive to pH value but was inversely proportional to zeta potential. The nano-TiO2 becomes more stable with surface zeta potential, accompanied by small particle size and high dispersion. In the presence of DOM, the particle size was smaller and the stability of nano-TiO2 could be enhanced. This might be a synergistic effect of the ligand exchange and electrostatic force. Particle size increased with the addition of Ca2+ and the stability decreased.

Isolation of naphthalene-degrading bacteria from tropical marine sediments

2003 ◽  
Vol 47 (1) ◽  
pp. 303-308 ◽  
Author(s):  
W.-Q. Zhuang ◽  
J.-H. Tay ◽  
A.M. Maszenan ◽  
S.T.-L. Tay
Keyword(s):  
Marine Sediments ◽  
Oil Pollution ◽  
Environmental Concern ◽  
Enrichment Culture ◽  
Ex Situ ◽  
Bacterial Cells ◽  
Biochemical Tests ◽  
Naphthalene Degradation ◽  
Degrading Bacteria ◽  
Specific Growth Rates

Oil pollution is a major environmental concern in many countries, and this has led to a concerted effort in studying the feasibility of using oil-degrading bacteria for bioremediation. Although many oil-degrading bacteria have been isolated from different environments, environmental conditions can impose a selection pressure on the types of bacteria that can reside in a particular environment. This study reports the successful isolation of two indigenous naphthalene-degrading bacteria from oil-contaminated tropical marine sediments by enrichment culture. Strains MN-005 and MN-006 were characterized using an extensive range of biochemical tests. The 16S ribosomal deoxyribonucleic acid (rDNA) sequence analysis was also performed for the two strains. Their naphthalene degradation capabilities were determined using gas chromatography and DAPI counting of bacterial cells. Strains MN-005 and MN-006 are phenotypically and phylogenetically different from each other, and belong to the genera Staphylococcus and Micrococcus, respectively. Strains MN-005 and MN-006 had maximal specific growth rates (μmax) of 0.082 ± 0.008 and 0.30 ± 0.02 per hour, respectively, and half-saturation constants (Ks) of 0.79 ± 0.10 and 2.52 ± 0.32 mg per litre, respectively. These physiological and growth studies are useful in assessing the potential of these indigenous isolates for in situ or ex situ naphthalene pollutant bioremediation in tropical marine environments.

scholarly journals Nitrilotriacetate Stimulation of Anaerobic Fe(III) Respiration by Mobilization of Humic Materials in Soil

2003 ◽  
Vol 69 (9) ◽  
pp. 5255-5262 ◽  
Author(s):  
Y. Luu ◽  
B. A. Ramsay ◽  
J. A. Ramsay
Keyword(s):  
Humic Substances ◽  
Direct Contact ◽  
Enrichment Culture ◽  
Nitrilotriacetic Acid ◽  
Soil Extract ◽  
Alginate Beads ◽  
Electron Shuttling ◽  
Humic Materials ◽  
Dialysis Membranes ◽  
Stimulation Of

ABSTRACT An enrichment culture capable of naphthalene mineralization reduced Fe(III) oxides without direct contact in anaerobic soil microcosms when the Fe(III) was placed in dialysis membranes or entrapped within alginate beads. Both techniques demonstrated that a component in soil, possibly humic materials, facilitated Fe(III) reduction when direct contact between cells and Fe(III) was not possible. The addition of the synthetic Fe(III) chelator, nitrilotriacetic acid (NTA), to soil enhanced Fe(III) reduction across the dialysis membrane and alginate beads, with the medium changing from clear to a dark brown color. An NTA-soil extract was more effective in Fe(III) reduction than the extracted soil itself. Characteristics of the NTA extract were consistent with that of humic substances. The results indicate that NTA improved Fe(III) reduction not by Fe(III) solubilization but by extraction of humic substances from soil into the aqueous medium. This is the first study in which stimulation of Fe(III) reduction through the addition of chemical chelators is shown to be due to the extraction of electron-shuttling compounds from the soil and not to solubilization of the Fe(III) and indicates that mobilization of humic materials could be an important component of anaerobic biostimulation.

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