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naturally occurring chromosomal gene transfer in thiobacillus versutus. 19852579532
the amino acid sequence of the cytochrome c-554(547) from the chemolithotrophic bacterium thiobacillus neapolitanus.an amino acid sequence is proposed for the cytochrome c-554(547) from the bacterium thiobacillus neapolitanus n.c.i.b. 8539). it consists of a polypeptide chain of 91 residues, with a pair of haem-attachment cysteine residues at positions 15 and 18. there is similarity in sequence with each of the halves of the sequence of the dihaem cytochromes c4 and with a cytochrome c-554(548) from a halophilic strain of paracoccus. detailed evidence for the amino acid sequence of the protein has been deposi ...19852988504
the major soluble cytochromes of the obligately aerobic sulfur bacterium, thiobacillus neapolitanus.four cytochromes were isolated from soluble extracts of the aerobic sulfur bacterium, thiobacillus neapolitanus. the two most abundant proteins were purified to homogeneity and thoroughly characterized. cytochrome c-554 (547) is a monomeric, small molecular weight protein which is unusual in having two well-resolved alpha peaks in uv-visible absorption spectra. the redox potential is 208 mv. native cytochrome c-549 is oligomeric, but has a subunit size of about 26,000. the yield of this protein ...19852990367
a comparative survey of several bacterial aa3-type cytochrome c oxidases.the aa3-type cytochrome c oxidases purified from nitrobacter agilis, thiobacillus novellus, nitrosomonas europaea, and pseudomonas am 1 were compared. they have haem a and copper atom as the prosthertic groups and show alpha and gamma absorption peaks at around 600 and 440 nm, respectively. each oxidase molecule is composed of two kinds of subunits. the n. agilis oxidase has 2 moles of haem a and 2 atoms of copper in the minimal structural unit composed of one molecule each of the two kinds of s ...19852991467
isolation and characterization of a blue copper protein from thiobacillus versutus.the blue copper protein induced during growth of thiobacillus versutus on methylamine was purified and characterized. it is an acidic protein (isoelectric point 4.7), contains one cu2+ ion/enzyme molecule, is a monomeric protein (molecular mass about 14 kda), has a maximum in its absorption spectrum at 596 nm (molar absorption coefficient 3.9 x 10(3) m-1 cm-1), shows an axial type-i electron paramagnetic resonance spectrum (g parallel = 2.239, g perpendicular = 2.046 and a parallel = 5.6 mt) and ...19852998794
mobilization of thiobacillus ferrooxidans plasmids among escherichia coli strains.nonconjugative thiobacillus ferrooxidans plasmids were mobilized at high frequencies among escherichia coli strains by the incp plasmid rp4 and at low frequencies by the incn plasmid r46, but not by the incw plasmid psa. the mobilization region of a nonconjugative t. ferrooxidans plasmid was located on a 5.3-kilobase t. ferrooxidans dna fragment.19853890747
microbial desulfurization of fossil fuels. 19853904605
phylogenetic analysis of the genera thiobacillus and thiomicrospira by 5s rrna sequences.5s rrna nucleotide sequences from thiobacillus neapolitanus, thiobacillus ferrooxidans, thiobacillus thiooxidans, thiobacillus intermedius, thiobacillus perometabolis, thiobacillus thioparus, thiobacillus versutus, thiobacillus novellus, thiobacillus acidophilus, thiomicrospira pelophila, thiomicrospira sp. strain l-12, and acidiphilium cryptum were determined. a phylogenetic tree, based upon comparison of these and other related 5s rrna sequences, is presented. the results place the thiobacilli ...19853924899
physiology of the thiobacilli: elucidating the sulphur oxidation pathway.bacteria of the genus thiobacillus can obtain energy from the chemolithotrophic oxidation of inorganic sulphur and its compounds (sulphide, thiosulphate and polythionates) and use this energy to support autotrophic growth on carbon dioxide. despite many decades of work on them, the precise details of the pathway(s) for sulphur oxidation are still obscure. in this article the latest state of knowledge is analysed and a likely mechanism developed that takes account of all the experimental data ava ...19853940000
cloning and expression of the thiobacillus ferrooxidans glutamine synthetase gene in escherichia coli.the glutamine synthetase (gs) gene glna of thiobacillus ferrooxidans was cloned on recombinant plasmid pmeb100 which enabled escherichia coli glna deletion mutants to utilize (nh4)2so4 as the sole source of nitrogen. high levels of gs-specific activity were obtained in the e. coli glna deletion mutants containing the t. ferrooxidans gs gene. the cloned t. ferrooxidans dna fragment containing the glna gene activated histidase activity in an e. coli glna glnl glng deletion mutant containing the kl ...19852866177
use of the respiration activity of thiobacillus ferrooxidans for the specific determination of iron(ii, iii).a method is described for the determination of fe2+ and fe3+ after its reduction to fe2+ on the basis of oxygen uptake rate as a function of fe2+ concentration. by using substrate-specific thiobacillus ferrooxidans in combination with the standard addition method a specific determination of iron(ii, iii) is possible with the determination limit of 3 mumol/l.19853996981
microbial desulfurization of coals in a slurry pipeline reactor using. thiobacillus ferrooxidans.microbial desulfurization of illinois #6 and indiana #3 bituminous coal having a total sulfur content of 2 to 8% has been investigated using acidophilic microorganism, thiobacillus ferrooxidans, in laboratory shake flash experiments and in a two-inch pipeline loop. the results indicate that about 80 to 85% pyritic sulfur removal was achieved with 10 to 25% coal/water slurry recirculated at 6-7 ft/sec at room temperature in 7 to 14 days. the experimental conditions have been optimized for maximum ...198520568162
regulation of internal ph in acidophilic and alkalophilic bacteria. 19863713537
chemostat enrichment and isolation of hyphomicrobium eg. a dimethyl-sulphide oxidizing methylotroph and reevaluation of thiobacillus ms1.a stable mixed bacterial culture was obtained by chemostat enrichment using dimethyl-sulphoxide as a carbon and energy source. this culture could not only rapidly oxidize dimethyl-sulphoxide but also dimethyl-sulphide. enzyme determinations indicated that an important part of it consisted of methylotrophs, which assimilated carbon via the serine pathway. indeed plate counts revealed the majority of the community to be a hyphomicrobium species. this organism, designated hyphomicrobium eg, is an o ...19863767349
kinetics and energetics of reduced sulfur oxidation by chemostat cultures of thiobacillus ferrooxidans.thiobacillus ferrooxidans was grown in chemostat cultures with thiosulfate and tetrathionate as the limiting substrates. the yields at steady state on both substrates at different dilution rates were calculated. in a few experiments the air supply was supplemented with 2% co2 (v/v). this resulted in a slightly increased yield. cells from the chemostat cultures were used to study the kinetics of thiosulfate, tetrathionate, sulfite and sulfide oxidation. with all substrates mentioned the ks values ...19863813523
discrimination between 34s and 32s during bacterial metabolism of inorganic sulfur compounds.sulfur isotope effects during the oxidation of thiosulfate by thiobacillus versutus were found to be negligible. this result is considered in relation to other oxidative and reductive processes to assess which reactions are most likely to control the isotopic compositions of sulfur compounds in microbial sulfureta.19863941049
purification, crystallization and preliminary x-ray investigation of quinoprotein methylamine dehydrogenase from thiobacillus versutus.the enzyme methylamine dehydrogenase or primary-amine:(acceptor) oxidoreductase (deaminating) (ec 1.4.99.3) was purified from the bacterium thiobacillus versutus to homogeneity, as judged by polyacrylamide gel electrophoresis. the native enzyme has a mr of 123 500 and contains four subunits arranged in a alpha 2 beta 2 configuration, the light and heavy subunits having a mr of 12900 and 47500 respectively. the isoelectric point is 3.9. the purified enzyme was crystallized from 37--42% saturated ...19863943535
tn5-induced mutations affecting sulfur-oxidizing ability (sox) of thiosphaera pantotropha.mutants of thiosphaera pantotropha defective in chemolithoautotrophic growth were obtained by transpositional mutagenesis with tn5 coding for kanamycin resistance. the suicide vehicle for introducing tn5 to t. pantotropha was psup5011 harbored by escherichia coli. kanamycin-resistant isolates were screened for the inability to grow with reduced sulfur compounds (sox-). four classes of sox- mutants were obtained. three were of different pleiotropic phenotypes: (i) unable to grow with formate, nit ...19863009400
sulfate-dependent iron oxidation by thiobacillus ferrooxidans: characterization of a new epr detectable electron transport component on the reducing side of rusticyanin.iron(ii) oxidation by ph 2.5 hcl-washed cells of thiobacillus ferrooxidans is known to be sulfate dependent. sulfate dependence of the autooxidation of a novel component in the electron transport pathway is demonstrated. this component exhibits an electron paramagnetic resonance (epr) signal in the oxidized state at g = 2.005 distinguishable from the g = 2.08 signal attributed to rusticyanin. the novel component is proposed to be a three-iron-sulfur cluster based upon the g value, lineshape, and ...19863010867
colonial heterogeneity of thiobacillus versutus.in acetate-limited chemostat cultures started with single-colony cultures of thiobacillus versutus, a mutant appeared after approximately 85 volume changes. the inhomogeneity of the culture was detected by the development of two different types of colonies on agar plates. when a pure culture of the mutant was grown in a chemostat, parent colonies appeared after almost the same period of time. electron micrographs of the mutant grown on butyrate showed the presence of fibrils surrounding the cell ...19863096960
[balance of macroergic compounds during the growth of thiobacillus ferrooxidans].the balance of energy-rich compounds (erc) was drawn up for the growth of thiobacillus ferrooxidans in a medium with ferrous ions as an energy source. the balance items and the phosphorylating efficiency of oxidation (p/2e-) were calculated basing on the experimental yield values using the erc balance equation. at a specific growth rate of 0.1 h-1, 55% of ferrous ions are used for the synthesis of cell biomass, 7.5% for maintainance, 4% of the ions are oxidized to reduce nad+, and 34% are used t ...19863102905
preservation of thiobacillus ferrooxidans and thiobacillus thiooxidans with activity check.cultures of thiobacillus ferrooxidans and thiobacillus thiooxidans, used in biohydrometallurgical processes of economic importance, are very difficult to preserve by conventional methods. hence, to preserve the cultures with their activity intact, various techniques were tried, after determining their respective activity in terms of iron oxidation rate (ior) and sulfur oxidation rate (sor). among the methods tested, along with the recommended method of serial transfer in a liquid medium, were me ...19863524447
microorganisms in reclamation of metals. 19863535647
identification and cloning of thiobacillus ferrooxidans structural nif genes in escherichia coli.the presence of nucleotide sequences which are homologous to the nifhdk genes of klebsiella pneumoniae was demonstrated in total dna preparations from five different iron-oxidizing thiobacillus ferrooxidans strains. a non-iron-oxidizing thiobacillus novellus strain and a heterotrophic acidiphilium strain, which occurs in close association with t. ferrooxidans, did not contain dna homologous to the nifhdk genes. the t. ferrooxidans atcc33020 nifhdk genes were cloned and their arrangement was char ...19863536666
enhancement of growth and ferrous iron oxidation rates of t. ferrooxidans by electrochemical reduction of ferric iron.thiobacillus ferrooxidans, the bacterium most widely used; in bioleaching or microbial desulfurization studies, was grown in an electrolytic bioreactor containing a synthetic, ferrous sulfate medium. passage of current through the medium reduced the bacterially generated ferric iron to the ferrous iron substrate. when used in conjunction with an inoculum that had been adapted to the electrolytic growth conditions, this technique increased the protein (cell) concentration by 3.7 times, increased ...198618555304
the adsorption of thiobacillus ferrooxidans on coal surfaces.the adsorption of thiobacillus ferrooxidans to coal surfaces has been studied. adsorption experiments were conducted on coal samples from eight different eastern coal fields. in all cases the adsorption process was at least 90% complete within the first two minutes following inoculation. the results of these experiments were used to test the validity of two proposed adsorption models. the first model assumes that bacterial adsorption follows second-order irreversible kinetics of the second kind ...198618555350
particle size effects in the microbiological leaching of sulfide concentrates by thiobacillus ferrooxidans. 198618555388
the removal of pyritic sulfur from coal employing thiobacillus ferrooxidans in a packed column reactor. 198718561139
oxidation of hydrogen sulfide by thiobacillus denitrificans: desulfurization of natural gas.it has been demonstrated that thiobacillus denitrificans may be readily cultivated anaerobically in batch reactors on h(2)s (g) under sulfide-limiting conditions. under these conditions sulfide concentrations in the culture medium were less than 1 microm, resulting in very low concentrations of h(2)s in the reactor outlet gas. the stoichiometry of the reaction was determined, and stable reactor operation was demonstrated at reactor loadings as high as 4-5 mmol h(2)s oxidized/h g biomass. maximum ...198718576383
aerobic oxidation of hydrogen sulfide by thiobacillus denitrificans.it has been demonstrated that thiobacillus denitrificans may be readily cultured aerobically in batch and continuous flow reactors on h(2)s(g) under sulfide limiting conditions. under these conditions sulfide concentrations in the culture medium were less than 1mum resulting in very low concentrations of h(2)s in the reactor outlet gas. biomass yield under aerobic conditions was much lower than previously reported for anaerobic conditions, presumably because of oxygen inhibition of growth. howev ...198718576503
oxidation of hydrogen sulfide by continuous cultures of thiobacillus denitrificans. 198718576511
oxidation of hydrogen sulfide by mixed cultures of thiobacillus denitrificans and heterotrophs. 198718576512
suppression of pyritic sulphur during flotation tests using the bacterium thiobacillus ferrooxidans.environmental concern about sulphur dioxide emissions has led to the examination of the possibility of removing pyritic sulphur from coal prior to combustion during froth flotation, a routine method for coal cleaning at the pit-head. the bacterium thiobacillus ferrooxidans was effective in leaching 80% and 63% -53 mum pyrite at 2% and 6% pulp density in shake flasks in 240 and 340 h, respectively.the natural floatability of pyrite was significantly reduced in the hallimond tube following 2.5 min ...198718576576
use of epifluorescence microscopy for characterizing the activity of thiobacillus ferrooxidans on iron pyrite.the enumeration and characterization of microorganisms attached to solid surfaces have always presented significant difficulties. this is particularly true for micro organisms that are indigenous to coal mines and mineral deposits where metal sulfides are ubiquitous. the complications that arise are the result of the variety of inorganic compounds that are present in these environments, the harsh conditions under which the microorganisms proliferate, and the low cell densities to which they grow ...198718576593
growth of free and attached thiobacillus ferrooxidans in ore suspension.the growth of thiobacillus ferrooxidans in a copper-containing ore suspension incubated in shake flasks was studied by determining the number of colony-forming units both in solution and attached to ore particles. the amounts of iron and copper released from the ore under experimental conditions were also determined. the total ferrous iron either released from the minerals or generated by reduction of the ferric iron in the minerals could account for the observed growth of bacteria in solution. ...198718581437
a combined immunofluorescence-dna-fluorescence staining technique for enumeration of thiobacillus ferrooxidans in a population of acidophilic bacteria.an antiserum raised against whole cells of thiobacillus ferrooxidans was allowed to react with a variety of acidophilic and nonacidophilic bacteria in an enzyme-linked immunosorbent assay and an indirect immunofluorescence assay. both experiments demonstrated that the antiserum was specific at the species level. this preparation was used to evaluate the role of t. ferrooxidans in the microbial desulfurization process. leaching experiments were performed, and the numbers of t. ferrooxidans cells ...198716347315
effects of cinnabar on pyrite oxidation by thiobacillus ferrooxidans and cinnabar mobilization by a mercury-resistant strain.the effect of cinnabar on pyrite oxidation by mercury-sensitive and mercury-resistant strains of thiobacillus ferrooxidans was investigated by using percolation columns. mercury-resistant strains oxidized pyrite in pyrite-cinnabar mixtures (1 and 10%, wt/wt), whereas a mercury-sensitive strain did not. elemental mercury was produced by the mercury-resistant strains growing in the pyrite-cinnabar mixtures in percolation columns and in flasks containing cinnabar only. manometric experiments showed ...198716347321
importance of hydrogen sulfide, thiosulfate, and methylmercaptan for growth of thiobacilli during simulation of concrete corrosion.biogenic sulfuric acid corrosion of concrete surfaces caused by thiobacilli was reproduced in simulation experiments. at 9 months after inoculation with thiobacilli, concrete blocks were severely corroded. the sulfur compounds hydrogen sulfide, thiosulfate, and methylmercaptan were tested for their corrosive action. with hydrogen sulfide, severe corrosion was noted. the flora was dominated by thiobacillus thiooxidans. thiosulfate led to medium corrosion and a dominance of thiobacillus neapolitan ...198716347391
growth of thiobacillus ferrooxidans on elemental sulfur.growth kinetics of thiobacillus ferrooxidans in batch cultures, containing prills of elementary sulfur as the sole energy source, were studied by measuring the incorporation of radioactive phosphorus in free and adsorbed bacteria. the data obtained indicate an initial exponential growth of the attached bacteria until saturation of the susceptible surface was reached, followed by a linear release of free bacteria due to successive replication of a constant number of adsorbed bacteria. these adsor ...198716347415
fractionation of stable carbon isotopes during chemoautotrophic growth of sulfur-oxidizing bacteria.laboratory-grown strains of chemoautotrophic thiomicrospira sp. strain l-12 and thiobacillus neapolitanus produced cell carbon that was 24.6 to 25.1 ppt (24.6 to 25.1 mg/g) lower in c isotope abundance than the ambient source of carbon dioxide and bicarbonate. this degree of c isotope depletion was comparable to that found in organic material produced in deep-sea hydrothermal-vent communities.198716347420
nucleotide sequence of the gene encoding the nitrogenase iron protein of thiobacillus ferrooxidans.the dna sequence was determined for the cloned thiobacillus ferrooxidans nifh and part of the nifd genes. a putative t. ferrooxidans nifh promoter was identified whose sequences showed perfect consensus with those of the klebsiella pneumoniae nif promoter. two putative consensus upstream activator sequences were also identified. the amino acid sequence was deduced from the dna sequence. in a comparison of nifh dna sequences from t. ferrooxidans and eight other nitrogen-fixing microbes, a rhizobi ...19873539923
structure-activity relationships of sparsomycin and its analogues. inhibition of peptide bond formation in cell-free systems and of l1210 and bacterial cell growth.the biological activity of 14 analogues of sparsomycin (1) was studied in cell-free systems of escherichia coli, saccharomyces cerevisiae, and sulfolobus solfataricus by measuring the inhibition of protein synthesis. the inhibition of l1210 colony formation in soft agar and bacterial cell growth in solid as well as in liquid medium was also examined. each analogue possesses not more than two structural modifications of the sparsomycin molecule. this enabled us to determine unambiguously several ...19873543365
phenylhydrazine as probe for cofactor identification in amine oxidoreductases. evidence for pqq as the cofactor in methylamine dehydrogenase.homogeneous methylamine dehydrogenase (primary-amine:(acceptor) oxidoreductase (deaminating), ec 1.4.99.3, madh) from the bacterium thiobacillus versutus was treated with the inhibitor phenylhydrazine (ph). derivatization of the cofactor in madh took place in a fast reaction to give compound i. a different product, compound ii, was formed in a slow reaction at high o2 concentrations. the compounds i and ii could be removed from the protein by proteolysis with pronase and purified to homogeneity. ...19873622768
purification and some properties of sulfur:ferric ion oxidoreductase from thiobacillus ferrooxidans.a sulfur:ferric ion oxidoreductase that utilizes ferric ion (fe3+) as an electron acceptor of elemental sulfur was purified from iron-grown thiobacillus ferrooxidans to an electrophoretically homogeneous state. under anaerobic conditions in the presence of fe3+, the enzyme reduced 4 mol of fe3+ with 1 mol of elemental sulfur to give 4 mol of fe2+ and 1 mol of sulfite, indicating that it corresponds to a ferric ion-reducing system (t. sugio, c. domatsu, o. munakata, t. tano, and k. imai, appl. en ...19873667519
respiratory enzymes of thiobacillus ferrooxidans. a kinetic study of electron transfer between iron and rusticyanin in sulfate media.thiobacillus ferrooxidans is a chemolithotrophic bacterium capable of fulfilling all of its energy requirements from the oxidation of soluble ferrous sulfate. rusticyanin is a soluble blue copper protein found in abundance in the periplasmic space of this bacterium. the one-electron transfer reaction between soluble iron and purified rusticyanin has been studied by stopped flow spectrophotometry in acidic solutions containing sulfate. second order rate constants for the reduction of rusticyanin ...19873667619
occurrence, identification and possible significance of ornithine lipid in thiobacillus ferrooxidans.an ornithine containing aminolipid has been found in thiobacillus ferrooxidans grown in ferrous sulfate medium, which was purified and estimated at four main phases of growth. glc analysis of ornithine lipid has revealed the existence of mainly c18:1 and c22:1 fatty acids. the infrared spectra showed the existence of both amide and ester linkages in the aminolipid. the major ester linked fatty acid was c22:1. the interaction of ornithine lipid with membrane was investigated by delipidation of th ...19873030307
two families of repeated dna sequences in thiobacillus ferrooxidans.the genome of thiobacillus ferrooxidans atcc 19859 is about 2.8 x 10(6) base pairs as determined by analysis of reassociation kinetics of sheared dna. this is 70% of the size of the genome of escherichia coli. about 6% of the genome of t. ferrooxidans consists of moderately repetitive dna sequences that are repeated an average of 20 times per genome. two distinct repeated sequences, designated family 1 and family 2, have been analyzed in more detail. both families are approximately 1 kilobase in ...19873032898
optical, epr and mössbauer spectroscopic studies on the no derivatives of cytochrome cd1 from thiobacillus denitrificans.we have used optical, epr and mössbauer spectroscopies to study the formation of heme-no complex upon the addition of nitrite to reduced cytochrome cd1 from thiobacillus denitrificans. the reduced d1 heme binds no under both alkaline and acidic conditions, but the binding of no to the reduced c heme was strongly ph-dependent. the mössbauer data showed unambiguously that at ph 7.6 the c heme does not complex no, whereas at ph 5.8 approximately half of the reduced c heme binds no. this observation ...19872826139
amino acid sequences of cytochrome c-554(548) and cytochrome c' from a halophilic denitrifying bacterium of the genus paracoccus.the amino acid sequences of the cytochromes c-554(548) and c' from the moderately halophilic bacterium paracoccus sp., i.a.m. 203 (= a.t.c.c. 12084, n.c.i.b. 8669) have been determined. cytochrome c-554(548) consists of a single polypeptide chain of 83 residues, and dimerizes strongly. the most similar protein of known sequence is the n-terminal half of the dihaem cytochrome c4, and other related proteins include the cytochrome c-554(547) of thiobacillus neapolitanus and the cytochrome c-553 of ...19872829828
nucleotide sequence of the glutamine synthetase gene and its controlling region from the acidophilic autotroph thiobacillus ferrooxidans.a 2089-bp chromosomal dna segment containing the thiobacillus ferrooxidans glna gene has been sequenced. putative glnap1-type promoter sequences, a consensus ntrc-gene-product-binding site and a catabolite-activating protein consensus recognition sequence were detected upstream of the structural gene. the glna gene was followed by a sequence resembling a rho-independent termination sequence. the complete amino acid sequence (468 residues) of the glutamine synthetase (gs) has been deduced, and co ...19872886400
purification and characterisation of glutamine synthetase from nocardia corallina.glutamine synthetase (gs) (ec 6.3.1.2) has been purified 67-fold from nocardia corallina. the apparent mr of the gs subunit was approximately 56,000. assuming the enzyme is a typical dodecamer this indicates a particle mass for the undissociated enzyme of 672,000. the gs is regulated by adenylylation and deadenylylation, and subject to feedback inhibition by alanine and glycine. the ph profiles assayed by the gamma-glutamyl transferase method were similar for nh+4-treated and untreated cell extr ...19882906794
reduction of mo6+ with elemental sulfur by thiobacillus ferrooxidans.in the presence of phosphate ions, molybdic ions (mo6+) were reduced enzymatically with elemental sulfur by washed intact cells of thiobacillus ferrooxidans to give molybdenum blue. the whole-cell activity that reduced mo6+ was totally due to cellular sulfur:ferric ion oxidoreductase (sforase) (t. sugio, w. mizunashi, k. inagaki, and t. tano, j. bacteriol. 169:4916-4922, 1987). the activity of m06+ reduction with elemental sulfur was competitively inhibited by fe3+, cu2+, and co2+. the michaelis ...19883056928
cloning and expression in escherichia coli of a reca-like gene from the acidophilic autotroph thiobacillus ferrooxidans.a recombinant plasmid, prsr100, containing the functional analogue of the escherichia coli reca gene was isolated from a genomic library of thiobacillus ferrooxidans atcc 33020. the plasmid complemented defects in dna repair and homologous recombination in e. coli reca mutant strains. antiserum raised against e. coli reca protein reacted with the native but defective e. coli hb101 reca protein; it did not react with protein extracts from the reca deletion mutant e. coli jk696, but it reacted wit ...19883058862
different lipid a types in lipopolysaccharides of phototrophic and related non-phototrophic bacteria.lipid a analyses confirm not only the present taxa of the purple nonsulfur bacteria (formerly rhodospirillaceae), but also phylogenetical relatedness of distinct phototrophic to distinct non-phototrophic bacteria, as was suggested by cataloguing 16s rrna. for example, lipid a with ester-bound 3-oh-10:0 and the rare amide-linked 3-oxo-14:0 is common to the phototrophic rhodobacter capsulatus and rhodobacter sphaeroides and also to paracoccus denitrificans and thiobacillus versutus. 'lipid adag' ( ...19883078741
[biology of chemoautotrophs]. 19883150584
ist2: an insertion sequence from thiobacillus ferrooxidans.the genome of thiobacillus ferrooxidans (strain atcc 19859) contains at least two families of repeated sequences, termed family 1 and 2. the nucleotide sequence of a family 2 member was determined. it is 1408 base pairs long and has structural features similar to those of insertion sequences (is elements). terminal inverted repeats 25 base pairs in length are present. these inverted repeats are imperfect and adjacent to target-site duplications 9 base pairs in length. several open reading frames ...19883174633
sequence and structural analysis of the alpha- and beta-dinitrogenase subunits of thiobacillus ferrooxidans.the structural genes (nifd and nifk) for the alpha and beta subunits of the molybdenum-iron (mofe) protein of the thiobacillus ferrooxidans dinitrogenase have been sequenced. the mr values deduced from the nucleotide sequences are 54,919 and 57,901 for the alpha and beta subunits, respectively. the amino acid sequences of both subunits were quantitatively compared with the equivalent subunits from other bacteria. distinct areas of amino acid homology were found between the alpha and beta subunit ...19883234769
existence of a new type of sulfite oxidase which utilizes ferric ions as an electron acceptor in thiobacillus ferrooxidans.a new type of sulfite oxidase which utilizes ferric ion (fe3+) as an electron acceptor was found in iron-grown thiobacillus ferrooxidans. it was localized in the plasma membrane of the bacterium and had a ph optimum at 6.0. under aerobic conditions, 1 mol of sulfite was oxidized by the enzyme to produce 1 mol of sulfate. under anaerobic conditions in the presence of fe3+, sulfite was oxidized by the enzyme as rapidly as it was under aerobic conditions. in the presence of o-phenanthroline or a ch ...19883345075
preliminary x-ray crystallographic study of amicyanin from thiobacillus versutus. 19883351942
phenotypic switching of thiobacillus ferrooxidans.two solid medium formulations, designated 100:10 and 10:10, were developed for the growth of thiobacillus ferrooxidans. the new media contain a mixture of both ferrous iron and thiosulfate as available energy sources, permitting the detection of colony morphology variants that arise spontaneously in a wild-type population. several morphological and physiological characteristics of a class of t. ferrooxidans variants, termed lsc for large spreading colony, are described. lsc variants lack the abi ...19883410820
a 1h-nmr study on the blue copper protein amicyanin from thiobacillus versutus. resonance identifications, structural rearrangements and determination of the electron self-exchange rate constant.a number of resonances in the 1h-nmr spectra of reduced and oxidised amicyanin from thiobacillus versutus have been identified by one- and two-dimensional nmr techniques. the second-order electron self-exchange rate constant (8.5 x 10(4) m-1.s-1; ph = 7.4; t = 308.5 k) was determined by measuring the line broadening of six singlets in slightly oxidised solutions of the protein. a large increase in electron exchange rate is observed in the presence of ferrocyanide. the copper atom in the reactive ...19883416870
sulfur-dependent inhibition of protein and rna synthesis by iron-grown thiobacillus ferrooxidans.the addition of sulfur to iron-grown thiobacillus ferrooxidans resulted in a rapid inhibition in the rates of protein synthesis and rna synthesis. the inhibition of both functions was measured within 15 to 30 min and was maximal between 70 and 90% compared to the iron-grown controls. dna synthesis, carbon dioxide fixation, and short-term ferrous oxidation rates of the bacteria growing on ferrous ions were not effected by sulfur addition, indicating that the sulfur addition was not perturbing gen ...19882454078
sequence of two trna genes from a thiobacillus ferrooxidans ribosomal operon. 19882458566
synthesis of an iron-oxidizing system during growth of thiobacillus ferrooxidans on sulfur-basal salts medium.it was found that the de novo synthesis of not only sulfur:ferric ion oxidoreductase (ferric ion-reducing system) but also iron oxidase was absolutely required when thiobacillus ferrooxidans ap19-3 was grown on sulfur-salts medium. the results strongly suggest that iron oxidase is involved in sulfur oxidation. this bacterium could not grow on sulfur-salts medium under anaerobic conditions with fe as a terminal electron acceptor, suggesting that energy conservation by electron transfer between el ...198816347521
oxidation of ferrous iron and elemental sulfur by thiobacillus ferrooxidans.the oxidation of ferrous iron and elemental sulfur by thiobacillus ferrooxidans that was absorbed and unabsorbed onto the surface of sulfur prills was studied. unadsorbed sulfur-grown cells oxidized ferrous iron at a rate that was 3 to 7 times slower than that of ferrous iron-grown cells, but sulfur-grown cells were able to reach the oxidation rate of the ferrous iron-adapted cells after only 1.5 generations in a medium containing ferrous iron. bacteria that were adsorbed to sulfur prills oxidiz ...198816347681
improved assay for rhodanese in thiobacillus spp.rhodanese (thiosulfate:cyanide sulfurtransferase; ec 2.8.1.1) catalyzes the conversion of thiosulfate and cyanide to thiocyanate and sulfite. conventional rhodanese assays colorimetrically measure the formation of one or the other of the products. these assays suffer from the fact that there is significant nonbiological formation of these products in addition to the enzymatically catalyzed reaction. in the present report, we describe a modified procedure for assaying rhodanese in which a separat ...198816347783
fast kinetics of fe oxidation in packed-bed reactors.thiobacillus ferrooxidans was used in fixed-film bioreactors to oxidize ferrous sulfate to ferric sulfate. glass beads, ion-exchange resin, and activated-carbon particles were tested as support matrix materials. activated carbon was tested in both a packed-bed bioreactor and a fluidized-bed bioreactor; the other matrix materials were used in packed-bed reactors. activated carbon displayed the most suitable characteristics for use as a support matrix of t. ferrooxidans fixed-film formation. the r ...198816347798
characterization of jarosite formed upon bacterial oxidation of ferrous sulfate in a packed-bed reactor.a packed-bed bioreactor with activated-carbon particles as a carrier matrix material inoculated with thiobacillus ferrooxidans was operated at a ph of 1.35 to 1.5 to convert ferrous sulfate to ferric sulfate. despite the low operating ph, trace amounts of precipitates were produced in both the reactor and the oxidized effluent. x-ray diffraction and chemical analyses indicated that the precipitates were well-ordered potassium jarosite. the chemical analyses also revealed a relative deficiency of ...198816347799
influence of some physicochemical parameters on bacterial activity of biofilm: ferrous iron oxidation by thiobacillus ferrooxidans.the influence of temperature, ph, and substrate and product concentrations on the oxidation rate of ferrous iron by biofilm of thiobacillus ferrooxidans was determined. the experiments were performed in an inverse fluidized-bed biofilm reactor in which the biofilm thickness was kept constant at 80 mum. oxygen concentration and diffusion through the biofilm did not limit the oxidation rate. the oxidation rate was almost unaffected by temperature between 13 and 38 degrees c, ph between 1.3 and 2.2 ...198818584607
biochemical limits to microbial growth yields: an analysis of mixed substrate utilization.a theoretical analysis has been made of carbon conversion efficiency during heterotrophic microbial growth. the expectation was that the maximal growth yield occurs when all the substrate is assimilated and the net flow of carbon through dissimilation is zero. this, however, is not identical to a 100% carbon conversion, since assimilatory pathways lead to a net production of co(2). it can be shown that the amount of co(2) produced by way of assimilatory processes is dependent upon the nature of ...198818584721
bacterial leaching of a sulfide ore by thiobacillus ferrooxidans and thiobacillus thiooxidans: i. shake flask studies.bacterial leaching of a sulfide ore containing pyrite, chalcopyrite, and sphalerite was studied in shake flask experiments using thiobacillus ferrooxidans and thiobacillus thiooxidans strains isolated from mine sites. the fe(2+)grown t. ferrooxidans isolates solubilized sphalerite preferentially over chalcopyrite leaching 7-10% cu, 68-76% zn, and 10-22% fe from the ore in 18 days. the sulfur grown t. thiooxidans isolates leached zn much more slowly and very little fe, with a cu-zn extraction rat ...198818584725
immunochemical localization of ribulose-1,5-bisphosphate carboxylase in the symbiont-containing gills of solemya velum (bivalvia: mollusca).the distribution of the calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase (rbup(2)case; ec 4.1.1.39) was examined by using two immunological methods in tissues of solemya velum, an atlantic coast bivalve containing putative chemoautotrophic symbionts. antibodies elicited by the purified large subunit of rbup(2)case from tobacco (nicotiana tabacum) cross-reacted on immunoblots with a protein of similar molecular mass occurring in extracts of the symbiont-containing gill tissue of s. velum ...198816593987
characterization of the cell wall murein of thiobacillus versutus.amino acid analysis of pure murein isolated from cells of thiobacillus versutus grown in complex medium revealed the typical constituents of most mureins from gram-negative cells, i.e. muramic acid, glucosamine, glutamic acid, alanine and diaminopimelic acid in molecular ratio of 0.58: 0.79: 1.0: 1.76:1.07, respectively. the presence of glycine and leucine was also demonstrated (0.20 and 0.08 compared to glutamic acid). glycine was also present in the murein of cells grown in chemically defined ...198821542391
an electrochemical method of measuring the oxidation rate of ferrous to ferric iron with oxygen in the presence of thiobacillus ferrooxidans.the oxidation of fe(2+) with oxygen in sulfate solutions was studied in the presence of t. ferrooxidans. to measure the chemical activity of bacteria, and the oxidation rate of iron, the redox potentials of solutions were continuously monitored during the experiments. the redox potentials were simultaneously monitored on the platinum and pyrite indicator electrodes. the redox potential versus time curves were further used to calculate the basic kinetic parameters, such as the reaction orders, th ...198918587934
novel technique for investigation and quantification of bacteriol leaching by thiobacillus ferrooxidans.a novel, efficient, and simple technique for the in situ study and quantification of the heterogeneous bacteriol activity and the bacteriol degradation of metal sulfides by thiobacillus ferrooxidans is presented. it consists of exposing an ultrathin (300-2500 a) metal sulfide layer, fes(2) in the experiments, to thiobacillus f. grown in touvinen media and visually following the bacteriol attack and development of bacteriol corrosion patterns under a light microscope. the uniform pyrite layer, pa ...198918588038
mathematical model for microbial oxidation of pure lead sulfide by thiobacillus ferrooxidans.a shrinking-core mathematical model describing bioleaching of lead sulfide is developed considering the deposition of insoluble bio-oxidation products on metal sulfide particle surfaces. variations in particle size are considered as it affects diffusion limitations.198918588129
sulfide and glutaraldehyde resistant strains of thiobacillus denitrificans. 198918588138
competitive inhibition of ferrous iron oxidation by thiobacillus ferrooxidans by increasing concentrations of cells.the oxidation of ferrous iron (fe) to ferric iron (fe) with dioxygen (o(2)) by various strains of thiobacillus ferrooxidans was studied by measuring the rate of o(2) consumption at various fe concentrations and cell concentrations. the apparent k(m) values for fe remained constant at different cell concentrations of laboratory strains atcc 13661 and atcc 19859 but increased with increasing cell concentrations of mine isolates sm-4 and sm-5. the latter results are explained by the competitive inh ...198916347904
specific dot-immunobinding assay for detection and enumeration of thiobacillus ferrooxidans.a specific and very sensitive dot-immunobinding assay for the detection and enumeration of the bioleaching microorganism thiobacillus ferrooxidans was developed. nitrocellulose spotted with samples was incubated with polyclonal antisera against whole t. ferrooxidans cells and then in i-labeled protein a or i-labeled goat antirabbit immunoglobulin g; incubation was followed by autoradiography. since a minimum of 10 cells per dot could be detected, the method offers the possibility of simultaneous ...198916347993
synergistic competitive inhibition of ferrous iron oxidation by thiobacillus ferrooxidans by increasing concentrations of ferric iron and cells.oxidation of ferrous iron by thiobacillus ferrooxidans sm-4 was inhibited competitively by increasing concentrations of ferric iron or cells. a kinetic analysis showed that binding of one inhibitor did not exclude binding of the other and led to synergistic inhibition by the two inhibitors. binding of one inhibitor, however, was affected by the other inhibitor, and the apparent inhibition constant increased with increasing concentrations of the other inhibitor.198916348031
rate equations and kinetic parameters of the reactions involved in pyrite oxidation by thiobacillus ferrooxidans.rate equations and kinetic parameters were obtained for various reactions involved in the bacterial oxidation of pyrite. the rate constants were 3.5 mum fe per min per fes(2) percent pulp density for the spontaneous pyrite dissolution, 10 mum fe per min per mm fe for the indirect leaching with fe, 90 mum o(2) per min per mg of wet cells per ml for the thiobacillus ferrooxidans oxidation of washed pyrite, and 250 mum o(2) per min per mg of wet cells per ml for the t. ferrooxidans oxidation of unw ...198916348054
nucleotide sequence of a thiobacillus ferrooxidans chromosomal gene, which encodes putative rna component of rnase p. 19892479918
porin from thiobacillus versutus.the porin of thiobacillus versutus ifo 14567 was isolated by extraction of cell-envelopes with sodium dodecyl sulfate. it exhibited strong porin-activity after reconstitution into artificial lipid bilayer membranes. the diameter of the pore was determined as 1.6 nm, with a weak selectivity for cations being observed. the porin migrated as a single band (mr 35 kda) on sds-polyacrylamide gel-electrophoresis after heating (100 degrees c, 5 min). the porin oligomer was not sensitive towards edta. an ...19892482223
nucleotide sequence and expression of a cloned thiobacillus ferrooxidans reca gene in escherichia coli.the nucleotide sequence of the reca gene of thiobacillus ferrooxidans has been determined. no sos box characteristic of lexa-regulated promoters could be identified in the 196-bp region upstream from the coding region. the cloned t. ferrooxidans reca gene was expressed in escherichia coli from both the lambda pr and lac promoters. it was not expressed from the 2.2-kb of t. ferrooxidans dna preceding the gene. the t. ferrooxidans reca gene specifies a protein of 346 amino acids that has 66% and 6 ...19892504646
the effect of thiosulphate and other inhibitors of autotrophic nitrification on heterotrophic nitrifiers.it has been found that heterotrophic nitrification by thiosphaera pantotropha can be inhibited by thiosulphate in batch and chemostat cultures. allythiourea and nitrapyrin, both classically considered to be specific inhibitors of autotrophic nitrification, inhibited nitrification by tsa. pantotropha in short-term experiments with resting cell suspensions. hydroxylamine inhibited ammonia oxidation in chemostat cultures, but was itself fully oxidized. thus the total nitrification rate for the cult ...19892515797
cytochrome oxidase of an acidophilic iron-oxidizing bacterium, thiobacillus ferrooxidans, functions at ph 3.5.cytochrome oxidase of thiobacillus ferrooxidans was partially purified. the oxidase preparation had haems a and c, and oxidized ferrocytochrome c-552 of the bacterium. the optimal ph of the reaction was 3.5. the enzyme also oxidized the reduced form of rusticyanin, a copper protein of the bacterium. our results indicate that the reduction of molecular oxygen by this enzyme may occur in the periplasm.19892541715
radioactive-electrophoretic assay of adenosine 5'-triphosphate sulfurylase activity in crude extracts with sulfate or selenate as a substrate.an assay method for atp sulfurylase is presented which employs na2(35)so4 as a substrate and measures the production of labeled adenosine 5'-phosphosulfate and 3'-phosphoadenosine 5'-phosphosulfate by low-voltage, hanging paper strip electrophoresis. the method is applicable to crude bacterial or mammalian extracts and accurately measures picomole amounts of product(s). na2(75seo4 can also be employed as a substrate, if the unstable radioactive product, adenosine 5'-phosphoselenate, is converted ...19892545107
thiobacillus ferrooxidans cytochrome c-552: purification and some of its molecular features.soluble cytochrome c-552 was purified from thiobacillus ferrooxidans to an electrophoretically homogeneous state. the cytochrome showed absorption peaks at 276, 411 and 523 nm in the oxidized form and peaks at 315, 417, 523 and 552 nm in the reduced form. the molecular weight of the cytochrome was estimated to be 13,800 on the basis of the amino acid composition and heme content, and 14,000 from sds-polyacrylamide gel electrophoresis analysis. its midpoint redox potential at ph 7.0 was determine ...19892551385
cloning and expression of thiobacillus versutus aspartate-semialdehyde dehydrogenase gene in escherichia coli.the thiobacillus versutus asd gene coding for aspartate-semialdehyde dehydrogenase was cloned in escherichia coli cells using pbr322 as a vector. the gene was expressed independently of its orientation, suggesting that e. coli rna polymerase recognized t. versutus promoter sequence. the t. versutus dna coded protein, of the molecular weight 44,000, was identified by the analysis of the proteins produced by minicells.19892567686
purification and some properties of thiosulphate-cleaving enzyme from thiobacillus novellus.a thiosulphate-cleaving enzyme was purified from thiobacillus novellus and some of its properties studied. the enzyme showed an absorption peak at 279 nm and no peaks between 300 and 650 nm. its mr was 38,000. although the crude enzyme cleaved thiosulphate to form sulphite without addition of cyanide, the purified enzyme required cyanide to cleave thiosulphate. the km values for thiosulphate and cyanide of the purified enzyme were 1.0 mm and 0.3 mm, respectively. one mol of the enzyme formed 10 ...19892612884
aerobic denitrification in various heterotrophic nitrifiers.various heterotrophic nitrifiers have been tested and found to also be aerobic denitrifiers. the simultaneous use of two electron acceptors (oxygen and nitrate) permits these organisms to grow more rapidly than on either single electron acceptor, but generally results in a lower yield than is obtained on oxygen, alone. one strain, formerly known as "pseudomonas denitrificans", was grown in the chemostat and shown to achieve nitrification rates of up to 44 nmol nh3 min-1 mg protein-1 and denitrif ...19892619286
cloning and expression of thiobacillus ferrooxidans mercury ion resistance genes in escherichia coli.a search of various domestic isolates of thiobacillus ferrooxidans revealed that some were fairly resistant to mercury ion. a proportion of mercury-resistant clones were able to volatilize mercury, and their corresponding gene was localized not in the plasmid dna but in chromosomal dna. this mercury ion resistance gene was cloned in escherichia coli. e. coli carrying the recombinant plasmid was able to grow in the presence of more than 40 micrograms of hgcl2 per ml. deletion analysis of the reco ...19892656656
nucleotide sequence of the thiobacillus ferrooxidans chromosomal gene encoding mercuric reductase.the nucleotide sequence of the thiobacillus ferrooxidans chromosomal mercuric-reductase-encoding gene (mera) has been determined. the mera gene contains 1635 bp, and shares 78.2% and 76.6% sequence homology with the transposon, tn501, and plasmid r100 mera genes, respectively. from the sequence, a 545-amino acid (aa) polypeptide was deduced, and comparison with those of tn501 and r100 revealed 80.6% and 80.0% homology, respectively, at the aa sequence level. divergence among the three mera aa se ...19892691338
identification and sequence of the basic replication region of a broad-host-range plasmid isolated from thiobacillus ferrooxidans.the minimum region required for replication of the broad-host-range thiobacillus ferrooxidans plasmid ptf-fc2 in escherichia coli was shown to be contained on a 2.05-kilobase fragment of dna. a 184-base-pair fragment that was required in cis for plasmid replication was identified. this region was also involved in plasmid incompatibility. nucleotide sequencing of this region revealed three perfectly conserved 22-base-pair tandemly repeated sequences. a comparison of this region with the equivalen ...19892708316
structure of quinoprotein methylamine dehydrogenase at 2.25 a resolution.the three-dimensional structure of quinoprotein methylamine dehydrogenase from thiobacillus versutus has been determined at 2.25 a resolution by a combination of multiple isomorphous replacement, phase extension by solvent flattening and partial structure phasing using molecular dynamics refinement. in the resulting map, the polypeptide chain for both subunits could be followed and an x-ray sequence was established. the tetrameric enzyme, made up of two heavy (h) and two light (l) subunits, is a ...19892792083
characterization of the two rrna gene operons present in thiobacillus ferrooxidans.the organization of rrna genes from the autotrophic, acidophilic bacterium thiobacillus ferrooxidans has been examined. two rrna operons were found in this microorganism by means of genomic hybridization studies. recombinant plasmids, ptr-3 and ptr-1 that carry a portion of 16/23 s rdna from one operon and the 5'-flanking region of the second operon, respectively, were identified and characterized.19892914622
removal of methanethiol, dimethyl sulfide, dimethyl disulfide, and hydrogen sulfide from contaminated air by thiobacillus thioparus tk-m.methanethiol, dimethyl sulfide, dimethyl disulfide, and hydrogen sulfide were efficiently removed from contaminated air by thiobacillus thioparus tk-m and oxidized to sulfate stoichiometrically. more than 99.99% of dimethyl sulfide was removed when the load was less than 4.0 g of dimethyl sulfide per g (dry cell weight) per day.19892930168
restriction map of thiobacillus versutus plasmid ptav1.a restriction map of thiobacillus versutus plasmid ptav1 was constructed using ecori, bamhi and sali restriction enzymes. knowledge of the restriction map is an obligatory starting point for genetic and molecular studies of this, so far cryptic, plasmid.19901715641
structure determination of quinoprotein methylamine dehydrogenase from thiobacillus versutus.the crystal structure of quinoprotein methylamine dehydrogenase from thiobacillus versutus (ec 1.4.99.3, mr = 123,500) has been solved to 2.25 a resolution. the crystals of space group p3(1)21 (a = b = 129.8, c = 104.3 a) contain half a tetrameric enzyme molecule in the asymmetric unit, with a solvent content of ca 70%. the procedure used to solve this structure involved multiple isomorphous-replacement phasing, complemented by phase extension using solvent flattening, and phase combination with ...19902085423
dynamic fluorescence in copper proteins. selected examples.the fluorescence properties of three copper proteins, namely human superoxide dismutase, pseudomonas aeruginosa azurin and thiobacillus versutus amicyanin have been studied. all these proteins show a non-exponential decay of fluorescence, though the tryptophanyl residues responsible for the emission are very differently located in the three proteins. all the three decays can be fitted by at least two lifetimes or better with one or two lorentzian-shaped, continuous distributions of lifetime. in ...19902096899
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