| transformation of acidiphilium by electroporation and conjugation. | two techniques, electroporation and conjugation, have been used to introduce the rk2-based broad-host-range plasmids prk415 and plafr3 into strains of the bacterial genus acidiphilium. using electroporation, cells were also transformed with a series of chimeric plasmids constructed by cloning cryptic acidiphilium plasmids into the escherichia coli vector pbr328. various parameters affecting electroporation were investigated. transformation efficiency varied widely with different recipient strain ... | 1992 | 1643582 |
| isolation and identification of restriction endonuclease aor51hi from acidiphilium organovorum 51h. | | 1992 | 1741262 |
| acpi, a novel isoschizomer of asuii from acidiphilium cryptum 25h, recognizes the sequence 5'tt decreases cgaa3'. | | 1991 | 1956800 |
| a plasma-membrane associated atpase from the acidophilic bacterium acidiphilium cryptum. | a membrane-bound atpase of acidiphilium cryptum, an acidophilic bacterium of mine origin, has been studied. the enzyme has a ph optimum of 8.4 mg2+ is required for its activity and could be replaced by mn2+, but not by ca2+. the enzyme shows a strong preference for atp as substrate, with the apparent km of about 0.2 mm. sulphite ion significantly stimulated the enzyme activity. n,n'-dicyclohexylcarbodiimide, oligomycin, and azide strongly inhibited the enzyme, whereas vanadate was without effect ... | 1990 | 2148483 |
| isolation and identification of restriction endonuclease asp35hi from acidiphilium species 35h. | | 1990 | 2235517 |
| restriction endonuclease afai from acidiphilium facilis, a new isoschizomer of rsai: purification and properties. | | 1989 | 2790034 |
| 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 ... | 1986 | 3536666 |
| 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 ... | 1985 | 3924899 |
| cultural and phylogenetic analysis of mixed microbial populations found in natural and commercial bioleaching environments. | a range of autotrophic and heterotrophic enrichment cultures were established to determine the cultural bacterial diversity present in samples obtained from the acidic runoff of a chalcocite overburden heap and from laboratory-scale (1- to 4-liter) batch and continuous bioreactors which were being used for the commercial assessment of the bioleachability of zinc sulfide ore concentrates. strains identified as thiobacillus ferrooxidans, thiobacillus thiooxidans, "leptospirillum ferrooxidans," and ... | 1994 | 7517131 |
| phylogenetic positions of novel aerobic, bacteriochlorophyll a-containing bacteria and description of roseococcus thiosulfatophilus gen. nov., sp. nov., erythromicrobium ramosum gen. nov., sp. nov., and erythrobacter litoralis sp. nov. | we analyzed the 16s ribosomal dnas of three obligately aerobic, bacteriochlorophyll a-containing bacteria, "roseococcus thiosulfatophilus," "erythromicrobium ramosum," and new isolate t4t (t = type strain), which was obtained from a marine cyanobacterial mat. "roseococcus thiosulfatophilus" is a member of the alpha-1 subclass of the proteobacteria and is moderately related to rhodopila globiformis, thiobacillus acidophilus, and acidiphilium cryptum (level of sequence similarity, 90%). "erythromi ... | 1994 | 7520734 |
| restriction endonuclease aor13hi from acidiphilium organovorum 13h, a new isoschizomer of bspmii: purification and characterization. | a restriction endonuclease, aor13hi, an isoschizomer of bspmii, was purified to homogeneity from cell extracts of acidiphilium organovorum strain 13h. the enzyme has a molecular mass of 60,000 daltons and consists of two subunits identical in molecular mass of 30,000 daltons. aor13hi endonuclease, like bspmii, recognizes the palindromic six-base sequence 5'-tccgga-3', and cleaves between the t and c to produce a four-base 5' extension. aor13hi is not inhibited by dam-dependent methylation. the i ... | 1993 | 7764267 |
| transformation of the acidophilic heterotroph acidiphilium facilis by electroporation. | we constructed a cloning vector for use in the acidophilic heterotroph acidiphilium facilis. the vector pah101 (8.8 kb) was constructed from a 6.1 kb restriction fragment of the acidiphilium plasmid pah1 and a puc19 carrying a beta-lactamase gene. the antibiotic resistance gene was efficiently expressed in a. facilis. several factors which influenced the transformation efficiency were optimized, resulting in a transformation efficiency of up to 3 x 10(3) transformants per microgram of plasmid dn ... | 1993 | 7764274 |
| transfer and expression of degradative and antibiotic resistance plasmids in acidophilic bacteria. | the genetic accessibility of selected acidophilic bacteria was investigated to evaluate their applicability to degrading pollutants in acidic environments. the incp1 antibiotic resistance plasmids rp4 and pvk101 and the phenol degradation-encoding plasmid ppgh11 were transferred from neutrophilic bacteria into the extreme acidophilic eubacterium acidiphilium cryptum at frequencies of 1.8 x 10(-2) to 9.8 x 10(-4) transconjugants per recipient cell. the incq antibiotic resistance plasmid psup106 w ... | 1994 | 8161188 |
| characterization of a new bacteriophage which infects bacteria of the genus acidiphilium. | a novel bacteriophage, termed phi ac1, that infects strains of the genus acidiphilium (acidophilic, heterotrophic, aerobic, gram-negative eubacteria) most commonly isolated from acidic mine drainage environments, has been discovered and several of its properties have been determined. this is the first report of a bacteriophage infecting such cells. the virion has a lambdoid morphology and is larger than lambda, as shown by electron microscopy and sucrose gradient centrifugation. the sedimentatio ... | 1993 | 8245857 |
| cloning and sequence of the reca gene of acidiphilium facilis. | | 1993 | 8371991 |
| transformation of escherichia coli with a large plasmid of acidiphilium multivorum aiu 301 encoding arsenic resistance. | acidiphilium multivorum aiu 301 isolated from acid mineral water had strong arsenic resistance. this bacterium harbored a number of plasmids with different molecular sizes. a plasmid of 56 kbp, named pkw301, was isolated from a. multivorum aiu 301. when pkw301 was transferred into escherichia coli jm109 by electroporation, an e. coli transformant carrying pkw301 exhibited resistance to sodium arsenite, sodium arsenate, and mercuric (ii) chloride. | 1997 | 9143138 |
| metal resistance in acidocella strains and plasmid-mediated transfer of this characteristic to acidiphilium multivorum and escherichia coli. | acidophilic heterotrophic strain gs19h of the genus acidocella exhibited extremely high resistance to cdso4 and znso4, with a mic of 1 m for each. the respective mics for an acidocella aminolytica strain were 400 and 600 mm. the mics of niso4 for the above strains were 200 and 175 mm, respectively. these strains were also resistant to cuso4, the mics being 20 and 40 mm, respectively. an acidocella facilis strain showed resistance only to znso4, with a mic of 150 mm. the metal salts, in general, ... | 1997 | 9361438 |
| nucleotide sequences of genes coding for photosynthetic reaction centers and light-harvesting proteins of acidiphilium rubrum and related aerobic acidophilic bacteria. | the nucleotide sequences of the puf operons of the zn-bacteriochlorophyll a (zn-bchl a)-containing photosynthetic aerobic bacteria, acidiphilium rubrum and acidiphilium angustum, were determined. the nucleotide sequences of the pufl and -m of acidiphilium cryptum, acidiphilium multivorum, and acidiphilium organovorum were also determined. the puf operons of a. rubrum and a. angustum contained pufb, -a, -l, -m, and -c as seen in other purple bacteria with an unknown gene directly upstream of pufb ... | 1997 | 9435141 |
| expression and regulation of the arsenic resistance operon of acidiphilium multivorum aiu 301 plasmid pkw301 in escherichia coli. | the arsenic resistance (ars) operon from plasmid pkw301 of acidiphilium multivorum aiu 301 was cloned and sequenced. this dna sequence contains five genes in the following order: arsr, arsd, arsa, arsb, arsc. the predicted amino acid sequences of all of the gene products are homologous to the amino acid sequences of the ars gene products of escherichia coli plasmid r773 and incn plasmid r46. the ars operon cloned from a. multivorum conferred resistance to arsenate and arsenite on e. coli. expres ... | 1998 | 9464374 |
| aerobic anoxygenic phototrophic bacteria. | the aerobic anoxygenic phototrophic bacteria are a relatively recently discovered bacterial group. although taxonomically and phylogenetically heterogeneous, these bacteria share the following distinguishing features: the presence of bacteriochlorophyll a incorporated into reaction center and light-harvesting complexes, low levels of the photosynthetic unit in cells, an abundance of carotenoids, a strong inhibition by light of bacteriochlorophyll synthesis, and the inability to grow photosynthet ... | 1998 | 9729607 |
| phylogeny and photosynthetic features of thiobacillus acidophilus and related acidophilic bacteria: its transfer to the genus acidiphilium as acidiphilium acidophilum comb. nov. | phylogenetic analyses based on 16s rdna sequences and genomic dna-dna relatedness showed that the sulphur-oxidizing facultative chemolithotroph thiobacillus acidophilus was closely related to members of the genus acidiphilium, which is a group of strictly aerobic, heterotrophic acidophiles now categorized into aerobic photosynthetic bacteria. lipophilic pigment analyses revealed that zinc-chelated bacteriochlorophyll a and carotenoids occurred in appreciable amounts in t. acidophilus and all est ... | 1998 | 9828441 |
| microbial reduction of fe(iii) in acidic sediments: isolation of acidiphilium cryptum jf-5 capable of coupling the reduction of fe(iii) to the oxidation of glucose. | to evaluate the microbial populations involved in the reduction of fe(iii) in an acidic, iron-rich sediment, the anaerobic flow of supplemental carbon and reductant was evaluated in sediment microcosms at the in situ temperature of 12 degrees c. supplemental glucose and cellobiose stimulated the formation of fe(ii); 42 and 21% of the reducing equivalents that were theoretically obtained from glucose and cellobiose, respectively, were recovered in fe(ii). likewise, supplemental h(2) was consumed ... | 1999 | 10427060 |
| magnesium insertion by magnesium chelatase in the biosynthesis of zinc bacteriochlorophyll a in an aerobic acidophilic bacterium acidiphilium rubrum. | to elucidate the mechanism for formation of zinc-containing bacteriochlorophyll a in the photosynthetic bacterium acidiphilium rubrum, we isolated homologs of magnesium chelatase subunits (bchi, -d, and -h). a. rubrum bchi and -h were encoded by single genes located on the clusters bchp-orf168-bchi-bchd-orf320-crti and bchf-n-b-h-l as in rhodobacter capsulatus, respectively. the deduced sequences of a. rubrum bchi, -d, and -h had overall identities of 59. 8, 40.5, and 50.7% to those from rba. ca ... | 1999 | 10559247 |
| magnetic circular dichroism properties of reaction center complexes isolated from the zinc-bacteriochlorophyll a-containing purple bacterium acidiphilium rubrum. | reaction center (rc) complexes isolated from a zn-bacteriochlorophyll (bchl) a-containing purple bacterium, acidiphilium rubrum, were characterized by absorption, circular dichroism, and magnetic circular dichroism (mcd) spectroscopy. the oxidized-minus-reduced difference spectra indicated that, in this rc, the zn-bchl a is the primary electron donor. the molecular structure of the donor was examined by measuring the ratio of the mcd intensity of the faraday b-term (b) to the dipole strength (d) ... | 2000 | 10747790 |
| ultrastructure of the acidophilic aerobic photosynthetic bacterium acidiphilium rubrum. | the ultrastructure of cells of acidiphilium rubrum, which is an acidophilic aerobic photosynthetic bacterium containing zinc-complexed bacteriochlorophyll a, was studied by electron microscopy with the rapid substitution technique. thin-section electron microscopy indicated that any type of internal photosynthetic membranes was not present in this organism despite a relatively high content of the photopigment. the majority of cells had poly-beta-hydroxybutyrate granules and electron-dense spheri ... | 2000 | 10827283 |
| ferroplasma acidiphilum gen. nov., sp. nov., an acidophilic, autotrophic, ferrous-iron-oxidizing, cell-wall-lacking, mesophilic member of the ferroplasmaceae fam. nov., comprising a distinct lineage of the archaea. | an isolate of an acidophilic archaeon, strain yt, was obtained from a bioleaching pilot plant. the organism oxidizes ferrous iron as the sole energy source and fixes inorganic carbon as the sole carbon source. the optimal ph for growth is 1.7, although growth is observed in the range ph 1.3 to 2.2. the cells are pleomorphic and without a cell wall. 16s rrna gene sequence analysis showed this strain to cluster phylogenetically within the order 'thermoplasmales' sensu woese, although with only 89. ... | 2000 | 10843038 |
| development and application of small-subunit rrna probes for assessment of selected thiobacillus species and members of the genus acidiphilium. | culture-dependent studies have implicated sulfur-oxidizing bacteria as the causative agents of acid mine drainage and concrete corrosion in sewers. thiobacillus species are considered the major representatives of the acid-producing bacteria in these environments. small-subunit rrna genes from all of the thiobacillus and acidiphilium species catalogued by the ribosomal database project were identified and used to design oligonucleotide dna probes. two oligonucleotide probes were synthesized to co ... | 2000 | 10877807 |
| acidisphaera rubrifaciens gen. nov., sp. nov., an aerobic bacteriochlorophyll-containing bacterium isolated from acidic environments. | four strains of aerobic, mesophilic, acidophilic bacteria that produced bacteriochlorophyll (bchl) a were isolated from acidic hot springs and mine drainage. the characteristics of the four isolates were almost identical. the isolates were strictly aerobic and chemo-organotrophic. they were gram-negative, non-motile cocci and coccobacilli, formed salmon-pink colonies on solidified media and produced bchl a and carotenoids only under aerobic growth conditions. the cells also produced small amount ... | 2000 | 10939661 |
| microbiology of acidic, geothermal springs of montserrat: environmental rdna analysis. | dna was extracted from water and sediment samples taken from acidic, geothermal pools on the caribbean island of montserrat. 16s rrna genes were amplified by pcr, cloned, sequenced, and examined to indicate some of the organisms that might be significant components of the in situ microbiota. a clone bank representing the lowest temperature pool that was sampled (33 degrees c) was dominated by genes corresponding to two types of acidophiles: acidiphilium-like mesophilic heterotrophs and thermotol ... | 2000 | 11057917 |
| [alleviation of type i restriction in escherichia coli k12 in the presence of the arsr gene from pkw301 of acidiphilium multivorum aiu 301]. | a study was made of the antirestriction activity of acidiphilium multivorum aiu 301 arsr, a repressor of the ars operon which confers resistance to arsenite and arsenate and is on pkw301. in escherichia coli, arsr cloned under the control of plac in a multi-copy vector alleviated restriction of nonmodified lambda dna by a factor of 120, six times more efficiently than its analogs of conjugal plasmids r64 (inci1) and r773 (incfi). amino acid sequence analysis showed that the three arsr proteins h ... | 2001 | 11234385 |
| attached and unattached bacterial communities in a 120-meter corehole in an acidic, crystalline rock aquifer. | the bacteria colonizing geologic core sections (attached) were contrasted with those found suspended in the groundwater (unattached) by examining the microbiology of 16 depth-paired core and groundwater samples using a suite of culture-independent and culture-dependent analyses. one hundred twenty-two meters was continuously cored from a buried chalcopyrite ore hosted in a biotite-quartz-monzonite porphyry at the mineral park mine near kingman, ariz. every fourth 1.5-m core was acquired using mi ... | 2001 | 11319087 |
| isolation and phylogenetic characterization of acidophilic microorganisms indigenous to acidic drainage waters at an abandoned norwegian copper mine. | the biodiversity of culturable acidophilic microbes in three acidic (ph 2.7-3.7), metal-rich waters at an abandoned subarctic copper mine in central norway was assessed. acidophilic bacteria were isolated by plating on selective solid media, and dominant isolates were identified from their physiological characteristics and 16s rrna gene sequences. the dominant iron-oxidizing acidophile in all three waters was an acidithiobacillus ferrooxidans-like eubacterium, which shared 98% 16s rdna identity ... | 2001 | 11722543 |
| reduction of ferric iron by acidophilic heterotrophic bacteria: evidence for constitutive and inducible enzyme systems in acidiphilium spp. | to compare the abilities of two obligately acidophilic heterotrophic bacteria, acidiphilium acidophilum and acidiphilium sjh, to reduce ferric iron to ferrous when grown under different culture conditions. | 2002 | 11849360 |
| beta-d-glucopyranosyl caldarchaetidylglycerol is the main lipid of the acidophilic, mesophilic, ferrous iron-oxidising archaeon ferroplasma acidiphilum. | chloroform-methanol-extractable lipids account for about 5% by weight of dry cells of the acidophilic, autotrophic, mesophilic, ferrous compound-oxidising, cell wall-less archaeon ferroplasma acidiphilum strain y(t), about 90% of these being contributed by phospholipids and glycophospholipids. the most abundant constituent (about 55% of total lipids) was purified by deae cellulose and silica gel column chromatography. by means of matrix-assisted laser desorption ionisation mass spectrometry, inf ... | 2002 | 11960749 |
| design and performance of rrna targeted oligonucleotide probes for in situ detection and phylogenetic identification of microorganisms inhabiting acid mine drainage environments. | at iron mountain, ca, there is an extreme occurrence of acid mine drainage (amd). this is a result of past mining activity that has exposed a sulfide ore body to weathering and microbial activity. this study presents seven new oligonucleotide probes for the detection of microorganisms at this amd site by fluorescent in situ hybridization. in the design of these probes we have accounted for a large body of 16s rrna sequence data recently compiled by us. this was obtained by pcr and cloning direct ... | 2001 | 12032620 |
| microbial reduction of fe(iii) in the presence of oxygen under low ph conditions. | in acidic, coal mining lake sediments, facultatively anaerobic acidiphilium species are probably involved in the reduction of fe(iii). previous results indicate that these bacteria can co-respire o2 and fe(iii). in this study, we investigated the capacity of the sediment microbiota to reduce fe(iii) in the presence of o2 at ph 3. in sediment microcosms with 4% o2 in the headspace, the concentration of fe(ii) increased at a rate of 1.03 micromol (g wet sediment)-1 day-1 within the first 7 days of ... | 2002 | 12123477 |
| resistance to cadmium and zinc in acidiphilium symbioticum km2 is plasmid mediated. | the acidophilic heterotroph, acidiphilium symbioticum km2, is highly resistant to several metals and harbors three plasmids of 3.8, 7.1, and 56 kb in size. the bacterium becomes extremely sensitive to metals when it is cured of its plasmids. a mini-plasmid library was constructed by ligating the plasmid dna fragments generated by mboi partial digestion into the bamhi site of pbluescriptii ks+. the lac(-)amp(r) transformants of escherichia coli dh5alpha, isolated after transformation with the lib ... | 2002 | 12177739 |
| microbial community in acidic hydrothermal waters of volcanically active white island, new zealand. | we report the first description of the microbial community in a stream of acidic hydrothermal waters on volcanically active white island, new zealand, using both molecular and microbiological methods. alpha- and beta-proteobacteria, green-sulfur bacteria, and uncultured firmicutes were identified from the community dna-based 16s rrna gene library. the same bacterial groups and the rhodophyte cyanidium caldarium were represented in enrichment cultures. c. caldarium, two firmicutes and an acidophi ... | 2002 | 12382119 |
| inducible aluminum resistance of acidiphilium cryptum and aluminum tolerance of other acidophilic bacteria. | aluminum ions are highly soluble in acidic environments. toxicity of aluminum ions for heterotrophic, facultatively and obligately chemolithoautotrophic acidophilic bacteria was examined. acidiphilium cryptum grew in glucose-mineral medium, ph 3, containing 300 mm aluminum sulfate [al(2)(so(4))(3)] after a lag phase of about 120 h with a doubling time of 7.6 h, as compared to 5.2 h of growth without aluminum. precultivation with 1 mm al(2)(so(4))(3) and transfer to a medium with 300 mm al(2)(so( ... | 2002 | 12420179 |
| recovery of novel bacterial diversity from a forested wetland impacted by reject coal. | sulphide mineral mining together with improperly contained sulphur-rich coal represents a significant environmental problem caused by leaching of toxic material. the savannah river site's d-area harbours a 22-year-old exposed reject coal pile (rcp) from which acidic, metal rich, saline runoff has impacted an adjacent forested wetland. in order to assess the bacterial community composition of this region, composite sediment samples were collected at three points along a contamination gradient (hi ... | 2002 | 12460285 |
| aerobic anoxygenic photosynthetic bacteria with zinc-bacteriochlorophyll. | naturally occurring chlorophyllous pigments, which function as the cofactor in the early photochemical reaction of photosynthesis, have been proven beyond question to be magnesium-complexed porphyrin derivatives. phototrophic organisms that use (bacterio)chlorophylls ([b]chls) containing metals other than mg were unknown for a long time. this common knowledge of natural photosynthesis has recently been modified by the striking finding that a novel purple pigment, zinc-chelated-bchl (zn-bchl) a, ... | 2001 | 12483616 |
| purification and some properties of a thermostable acid esterase from acidiphilium sp. aiu 409. | extracellular and cell-bound esterases produced by acidiphilium sp. aiu 409 were homogeneously purified from culture broth and cells, respectively, and some properties were investigated. both esterases more rapidly hydrolyzed p-nitrophenyl acyl esters containing long-chain fatty acids from c 8:0 to c 18:0 than those containing short-chain fatty acids from c 2:0 to c 6:0. the km values for p-nitrophenyl long-chain fatty acid esters from c 8:0 to c 18:0 were approximately 1.3-1.5 mm. the enzymes w ... | 1997 | 12501330 |
| influence of heterotrophic microbial growth on biological oxidation of pyrite. | the rate and extent of pyrite oxidation by the iron-oxidizing bacteria acidithiobacillus ferrooxidans was limited by the growth of the heterotrophic microbe acidiphilium acidophilum. in batch systems containing a mixture of both organisms, the maximum zero-order rate of ferric iron accumulation was about 1.4 mg of fe3+ l(-1) d(-1) as compared to 9.4 mg of fe3+ l(-1) d(-1) for pure cultures of a. ferrooxidans under the same conditions. pyrite oxidation was limited in cases where both cultures of ... | 2002 | 12521179 |
| [phenotypic features of ferroplasma acidiphilum strains yt and y-2]. | earlier, we described a new family of mesophilic, strictly autotrophic fe(2+)-oxidizing archaebacteria, ferroplasmaceae, which belongs to the order thermoplasmales and includes the genus ferroplasma and species f. acidiphilum (strain yt) [1]. the present work is concerned with a comparative study of phenotypic characteristics of the type strain yt and a new strain, f. acidiphilum y-2, isolated from dense pulps produced during oxidation of arsenogold concentrates from the bakyrchikskoe (kazakhsta ... | 2002 | 12526203 |
| generation of novel plasmids in escherichia coli s17-1(psup106). | when the highly metal-resistant acidophilic heterotrophic strain, acidiphilium symbioticum km2, was incubated with two escherichia coli strains, viz. s17-1 (psup106) and k12, on a medium that supported growth of these two divergent species of different habitats, e. coli transconjugants were isolated that contained novel plasmids and were resistant to zn(2+) (48 m m), cu(2+) (12 m m), ni(2+) (12 m m), chloramphenicol (50 microg/ml), and tetracycline (25 microg/ml). the transconjugant plasmids did ... | 2003 | 12732957 |
| the sulfane sulfur of persulfides is the actual substrate of the sulfur-oxidizing enzymes from acidithiobacillus and acidiphilium spp. | to identify the actual substrate of the glutathione-dependent sulfur dioxygenase (ec 1.13.11.18) elemental sulfur oxidation of the meso-acidophilic acidithiobacillus thiooxidans strains dsm 504 and k6, acidithiobacillus ferrooxidans strain r1 and acidiphilium acidophilum dsm 700 was analysed. extraordinarily high specific sulfur dioxygenase activities up to 460 nmol x min(-1) (mg protein)(-1) were found in crude extracts. all cell-free systems oxidized elemental sulfur only via glutathione persu ... | 2003 | 12855721 |
| microbial ecology of an extreme acidic environment, the tinto river. | the tinto river (huelva, southwestern spain) is an extreme environment with a rather constant acidic ph along the entire river and a high concentration of heavy metals. the extreme conditions of the tinto ecosystem are generated by the metabolic activity of chemolithotrophic microorganisms thriving in the rich complex sulfides of the iberian pyrite belt. molecular ecology techniques were used to analyze the diversity of this microbial community. the community's composition was studied by denatur ... | 2003 | 12902280 |
| cellular polyamines of the acidophilic, thermophilic and thermoacidophilic archaebacteria, acidilobus, ferroplasma, pyrobaculum, pyrococcus, staphylothermus, thermococcus, thermodiscus and vulcanisaeta. | cellular polyamines of newly isolated acidophilic, thermophilic and thermoacidophilic archaebacteria were investigated for the chemotaxonomic significance of polyamine distribution profiles. in addition to spermidine, spermine and agmatine, a quaternary branched penta-amine, n(4)-bis(aminopropyl)spermidine, was found in thermophilic thermococcus waiotapuensis, thermococcus aegaeus and pyrococcus glycovorans belonging to the order thermococcales. an acidophilic euryarchaeon, ferroplasma acidiphil ... | 2003 | 14673752 |
| high-rate ferric sulfate generation by a leptospirillum ferriphilum-dominated biofilm and the role of jarosite in biomass retention in a fluidized-bed reactor. | the aims of this work were to develop a high-rate fluidized-bed bioprocess for ferric sulfate production, to characterize biomass retention, and to determine the phylogeny of the enrichment culture. after 7 months of continuous enrichment and air aeration at 37 degrees c, the iron oxidation rate of 8.2 g fe(2+) l(-1)h(-1) (4.5.10(-12) g fe(2+) cell(-1) h(-1)) was obtained at a hydraulic retention time (hrt) of 0.6 h. however, oxygen supply became the rate-limiting factor. with gas mixture (99.5% ... | 2004 | 14991647 |
| characterization of ferroplasma isolates and ferroplasma acidarmanus sp. nov., extreme acidophiles from acid mine drainage and industrial bioleaching environments. | three recently isolated extremely acidophilic archaeal strains have been shown to be phylogenetically similar to ferroplasma acidiphilum y(t) by 16s rrna gene sequencing. all four ferroplasma isolates were capable of growing chemoorganotrophically on yeast extract or a range of sugars and chemomixotrophically on ferrous iron and yeast extract or sugars, and isolate "ferroplasma acidarmanus" fer1(t) required much higher levels of organic carbon. all four isolates were facultative anaerobes, coupl ... | 2004 | 15066799 |
| macrofilamentous microbial communities in the metal-rich and acidic river tinto, spain. | a novel type of macroscopic microbial community consisting of large dendritic filaments (up to 1.5 m) in a ph 2.0 dam of the river tinto (south-western spain) is described. the combined use of 16s rrna-gene surveys and fluorescent in situ hybridisation (fish) suggested that gamma-proteobacteria and a relative large diversity of alpha-proteobacteria dominated these structures. beta-proteobacteria, actinobacteria and firmicutes were also detected. whereas acidophilic bacteria of the genera acidith ... | 2004 | 15183867 |
| genetics of metal resistance in acidophilic prokaryotes of acidic mine environments. | acidophilic bacteria inhabiting acidic mine regions cause natural leaching of sulphidic ores. they are now exploited in industrial operations for leaching of metals and beneficiation of low-grade and recalcitrant ores. recent trends emphasize application of thermoacidophiles and genetic engineering of ore-leaching bacteria for greater success in this area. this requires an in-depth understanding on the molecular genetics of these bacteria and construction of cloning vectors for them. metal resis ... | 2004 | 15274476 |
| detection of acidithiobacillus ferrooxidans in acid mine drainage environments using fluorescent in situ hybridization (fish). | an important microorganism of acid mine drainage (amd) and bioleaching environments is acidithiobacillus ferrooxidans which oxidizes ferrous iron and generates ferric iron, an oxidant. most investigations to understand microbial aspects of sulfide mineral dissolution have focused on understanding physiological, metabolic, and genetic characteristics of a. ferrooxidans. in this study, a 16s rrna oligonucleotide probe designated s-s-t.ferr-0584-a-a-18, and labeled at the 5'-end with indocarbocyani ... | 2005 | 15676194 |
| isolation and characterisation of the lipopolysaccharide from acidiphilium strain gs18h/atcc55963, a soil isolate of indian copper mine. | the lipopolysaccharide (lps) of the gram-negative acidiphilium strain gs18h/atcc55963, a new soil isolate, exhibited very low endotoxic activity as determined by limulus gelation activity, lethal toxicity in galactosamine (galn) sensitised mice, and level of tumor necrosis factor alpha (tnfalpha) in the blood serum of balb/c mice. analysis of the lps, specially of lipid a which usually accounts for the toxicity, revealed the latter to contain glucosamine and phosphate besides fatty acids, of whi ... | 2005 | 15899404 |
| a novel alpha-glucosidase from the acidophilic archaeon ferroplasma acidiphilum strain y with high transglycosylation activity and an unusual catalytic nucleophile. | ferroplasma acidiphilum strain y (dsm 12658), a ferrous iron-oxidizing, acidophilic and mesophilic archaeon, was found to produce a membrane-bound alpha-glucosidase (alphaglufa) showing no significant similarity to any of the known glycoside hydrolases classified in different families and having an unusual catalytic site consisting of a threonine and a histidine residue. the highest alpha-glucosidase activity was found at low ph, 2.4-3.5, and the substrate preference order was: sucrose>maltose>m ... | 2005 | 15954864 |
| ferroplasma and relatives, recently discovered cell wall-lacking archaea making a living in extremely acid, heavy metal-rich environments. | for several decades, the bacterium acidithiobacillus (previously thiobacillus) has been considered to be the principal acidophilic sulfur- and iron-oxidizing microbe inhabiting acidic environments rich in ores of iron and other heavy metals, responsible for the metal solubilization and leaching from such ores, and has become the paradigm of such microbes. however, during the last few years, new studies of a number of acidic environments, particularly mining waste waters, acidic pools, etc., in d ... | 2005 | 16104851 |
| diversity and functional analysis of bacterial communities associated with natural hydrocarbon seeps in acidic soils at rainbow springs, yellowstone national park. | in this paper we describe the bacterial communities associated with natural hydrocarbon seeps in nonthermal soils at rainbow springs, yellowstone national park. soil chemical analysis revealed high sulfate concentrations and low ph values (ph 2.8 to 3.8), which are characteristic of acid-sulfate geothermal activity. the hydrocarbon composition of the seep soils consisted almost entirely of saturated, acyclic alkanes (e.g., n-alkanes with chain lengths of c15 to c30, as well as branched alkanes, ... | 2005 | 16204508 |
| bioleaching of sulfidic tailing samples with a novel, vacuum-positive pressure driven bioreactor. | this study presents a design for a novel bioreactor that uses alternating vacuum and positive pressure cycles to transfer acidic leach solution in and out of contact with finely ground sulfidic mine tailings. these tailings constitute an environmental problem that needs experimental data to support the development of management and control strategies. a conventional stirred tank bioreactor was used as a reference system. both bioreactors were inoculated with mixed cultures of acidophilic iron an ... | 2005 | 16245345 |
| effects of soluble ferri-hydroxide complexes on microbial neutralization of acid mine drainage. | heterotrophic respiration of ferric iron by acidiphilium cryptum was investigated in anoxic microcosms with initial media ph values from 1.5 to 3.5. no organic carbon consumption or iron reduction was observed with an initial ph of 1.5, indicating that a. cryptum may not be capable of iron respiration at this ph. significant iron reduction was observed at ph 2.5 and 3.5, with different effects. when the initial ph was 3.5, ph increased to 4.7-5.5 over 60 days of incubation with simultaneous prod ... | 2005 | 16295843 |
| analysis of differential protein expression during growth states of ferroplasma strains and insights into electron transport for iron oxidation. | to investigate the metabolic biochemistry of iron-oxidizing extreme acidophiles, a proteomic analysis of chemomixotrophic and chemo-organotrophic growth, as well as protein expression in the absence of organic carbon, was carried out in ferroplasma species. electron transport chain inhibitor studies, spectrophotometric analysis and proteomic results suggest that oxidation of ferrous iron may be mediated by the blue copper-haem protein sulfocyanin and the derived electron passes to a cbb3 termina ... | 2005 | 16339958 |
| mixotrophic growth of a thiobacillus ferrooxidans strain. | mixotrophic growth of a thiobacillus ferrooxidans strain is described. dna moles percent guanine plus cytosine and homology determinations confirmed that the mixotrophically grown t. ferrooxidans cultures were not contaminated with heterotrophic acidiphilium strains. | 1984 | 16346498 |
| glucose catabolism in strains of acidophilic, heterotrophic bacteria. | pathways of glucose catabolism, potentially operational in six strains of obligately aerobic, acidophilic bacteria, including acidiphilium cryptum strain lhet2, were investigated by short-term radiorespirometry and enzyme assays. short-term radiorespirometry was conducted at ph 3.0 with specifically labeled [c]glucose. the high rate and yield of c-1 oxidized to co(2) indicated that the entner-doudoroff, pentose phosphate, or both pathways were operational in all strains. apparent nonequivalent y ... | 1985 | 16346876 |
| ferric iron reduction by acidophilic heterotrophic bacteria. | fifty mesophilic and five moderately thermophilic strains of acidophilic heterotrophic bacteria were tested for the ability to reduce ferric iron in liquid and solid media under aerobic conditions; about 40% of the mesophiles (but none of the moderate thermophiles) displayed at least some capacity to reduce iron. both rates and extents of ferric iron reduction were highly strain dependent. no acidophilic heterotroph reduced nitrate or sulfate, and (limited) reduction of manganese(iv) was noted i ... | 1991 | 16348395 |
| diversity of 16s ribosomal dna-defined bacterial population in acid rock drainage from japanese pyrite mine. | four acidophilic bacteria (yards1-4) were isolated from an acid rock drainage (ard) from yanahara mine, okayama prefecture, japan. the physiological and 16s rdna sequence analyses revealed that yard1 was closely affiliated with acidithiobacillus ferrooxidans, yard2 was an acidiphilium-like bacterium, and yard3 and yard4 were sulfur-oxidizing bacteria with a relatively close relationship to a. ferrooxidans in the phylogenetic analysis. a molecular approach based on the construction of a 16s rdna ... | 2005 | 16473774 |
| the 'ph optimum anomaly' of intracellular enzymes of ferroplasma acidiphilum. | a wide range of microorganisms, the so-called acidophiles, inhabit acidic environments and grow optimally at ph values between 0 and 3. the intracellular ph of these organisms is, however, close to neutrality or slightly acidic. it is to be expected that enzymatic activities dedicated to extracellular functions would be adapted to the prevailing low ph of the environment (0-3), whereas intracellular enzymes would be optimally active at the near-neutral ph of the cytoplasm (4.6-7.0). the genes of ... | 2006 | 16478448 |
| direct 5s rrna assay for monitoring mixed-culture bioprocesses. | this study demonstrates the efficacy of a direct 5s rrna assay for the characterization of mixed microbial populations by using as an example the bacteria associated with acidic mining environments. the direct 5s rrna assay described herein represents a nonselective, direct molecular method for monitoring and characterizing the predominant, metabolically active members of a microbial population. the foundation of the assay is high-resolution denaturing gradient gel electrophoresis (dgge), which ... | 1996 | 16535333 |
| ferroplasma cupricumulans sp. nov., a novel moderately thermophilic, acidophilic archaeon isolated from an industrial-scale chalcocite bioleach heap. | a new species of archaea was isolated from an industrial mineral sulphide bioleach heap. strain bh2, a non-motile pleomorphic coccus, was capable of chemomixotrophic growth on ferrous sulphate and yeast extract. growth was not supported in the absence of yeast extract. phylogenetic analysis based on the 16s rrna gene showed that strain bh2 was most closely related to the species ferroplasma acidiphilum; however, it showed only 95% sequence similarity with this species. strain bh2 had a temperatu ... | 2006 | 16721487 |
| microbial populations identified by fluorescence in situ hybridization in a constructed wetland treating acid coal mine drainage. | microorganisms are an integral part of the biogeochemical processes in wetlands, yet microbial communities in sediments within constructed wetlands receiving acid mine drainage (amd) are only poorly understood. the purpose of this study was to characterize the microbial diversity and abundance in a wetland receiving amd using fluorescence in situ hybridization (fish) analysis. seasonal samples of oxic surface sediments, comprised of fe(iii) precipitates, were collected from two treatment cells o ... | 2006 | 16825452 |
| high-yielding plasmid extraction method from acidophilic heterotrophic bacteria of the genus acidiphilium. | plasmid yield from acidiphilium strains always had been poor following various standard methods. we adopted some simple modifications in the alkaline lysis procedure to get a better yield of plasmid from these bacteria. an approximately 10- to 20-fold increase in the plasmid yield was achieved when harvested acidiphilium cells were preincubated 16-20 h at ph 6 in nitrogen-free medium. another independent approach showed that freezing (-18 to -20 degrees c) of the harvested cells initially and at ... | 2006 | 16859629 |
| acidophilic microbial communities associated with a natural, biodegraded hydrocarbon seepage. | characterization of microbial communities present in a surface petroleum seep in which hydrocarbons have been biodegraded for thousands of years in order to improve the understanding on natural petroleum biodegradation. dna was extracted from a natural, surface petroleum seep and subjected to culture independent analysis (rrna gene-based denaturing gradient gel electrophoresis and phylogenetic analysis of clone libraries). molecular analysis suggested dominance by acidophilic bacteria, especiall ... | 2006 | 16882136 |
| immunobiological activities of a new nontoxic lipopolysaccharide from acidiphilium gs18h/atcc55963, a soil isolate from an indian copper mine. | a novel nontoxic lipopolysaccharide (lps) was purified from acidiphilium strain gs18h/atcc55963. the chemical composition of the lipid a part of this lps is distinctly different from that of known lipid a molecules. the lps was investigated to determine its capacity to provide protection against toxic lps or endotoxic shock, as has been reported for other nontoxic lpss (rhodobacter sphaeroides and rhodobacter capsulatus), and also the extent and type of immunomodulatory response in terms of tumo ... | 2006 | 16965358 |
| cultivation-dependent and cultivation-independent characterization of the microbial community in acid mine drainage associated with acidic pb/zn mine tailings at lechang, guangdong, china. | cultivation-based and molecular approaches were used to characterize the phylogenetic composition and structure of the microbial community in an extremely acidic (ph 2.0) acid mine drainage (amd) associated with pb/zn mine tailings that were undergoing vigorous acid generation. acidophilic bacteria were isolated and enumerated on solid media, and were found to be restricted to isolates related to acidithiobacillus ferrooxidans and acidiphilium cryptum. by contrast, cloning and phylogenetic analy ... | 2007 | 17059483 |
| succession of sulfur-oxidizing bacteria in the microbial community on corroding concrete in sewer systems. | microbially induced concrete corrosion (micc) in sewer systems has been a serious problem for a long time. a better understanding of the succession of microbial community members responsible for the production of sulfuric acid is essential for the efficient control of micc. in this study, the succession of sulfur-oxidizing bacteria (sob) in the bacterial community on corroding concrete in a sewer system in situ was investigated over 1 year by culture-independent 16s rrna gene-based molecular tec ... | 2007 | 17142362 |
| energy and electron transfer in the photosynthetic reaction center complex of acidiphilium rubrum containing zn-bacteriochlorophyll a studied by femtosecond up-conversion spectroscopy. | a photosynthetic reaction center (rc) complex was isolated from a purple bacterium, acidiphilium rubrum. the rc contains bacteriochlorophyll a containing zn as a central metal (zn-bchl a) and bacteriopheophytin a (bphe a) but no mg-bchl a. the absorption peaks of the zn-bchl a dimer (p(zn)), the accessory zn-bchl a (b(zn)), and bphe a (h) at 4 k in the rc showed peaks at 875, 792, and 753 nm, respectively. these peaks were shorter than the corresponding peaks in rhodobacter sphaeroides rc that h ... | 2007 | 17169326 |
| the cellular machinery of ferroplasma acidiphilum is iron-protein-dominated. | ferroplasma is a genus of the archaea, one of the three branches of the tree of life, and belongs to the order thermoplasmatales (euryarchaeota), which contains the most acidophilic microbes yet known. ferroplasma species live in acid mine drainage, acidic pools and environments containing sulphidic ores such as pyrite and characterized by ph values of 0-2 and high concentrations of ferrous iron and other heavy metals. f. acidiphilum strain y(t) is a chemoautotroph that grows optimally at ph 1.7 ... | 2007 | 17203061 |
| microbial communities in a porphyry copper tailings impoundment and their impact on the geochemical dynamics of the mine waste. | the distribution and diversity of acidophilic bacteria of a tailings impoundment at the la andina copper mine, chile, was examined. the tailings have low sulfide (1.7% pyrite equivalent) and carbonate (1.4% calcite equivalent) contents and are stratified into three distinct zones: a surface (0-70-80 cm) 'oxidation zone' characterized by low-ph (2.5-4), a 'neutralization zone' (70-80 to 300-400 cm) and an unaltered 'primary zone' below 400 cm. a combined cultivation-dependent and biomolecular app ... | 2007 | 17222129 |
| reduction of cr(vi) under acidic conditions by the facultative fe(lll)-reducing bacterium acidiphilium cryptum. | the potential for biological reduction of cr(vi) under acidic conditions was evaluated with the acidophilic, facultatively metal-reducing bacterium acidiphilium cryptum strain jf-5 to explore the role of acidophilic microorganisms in the cr cycle in low-ph environments. an anaerobic suspension of washed a. cryptum cells rapidly reduced 50 microm cr(vi) at ph 3.2; biological reduction was detected from ph 1.7-4.7. the reduction product, confirmed by xanes analysis, was entirely cr(iii) that was a ... | 2007 | 17265940 |
| nucleotide sequence analysis of cryptic plasmid pam5 from acidiphilium multivorum. | plasmid pam5 of acidiphilium multivorum jcm-8867 has been completely sequenced by initial cloning of hindiii-psti fragments followed by primer walking. it has a size of 5161bp and single site for several restriction enzymes as revealed by dna sequencing. sequence analysis predicts five putative open reading frames. orf1 and orf3 show significant identity with various plasmid encoded mobilization (mob) and replication initiation (rep) proteins, respectively. the putative mob protein has several c ... | 2007 | 17363056 |
| [isolation and characterization of acidiphilium strain teng-a and its metabolism of fe (iii) during pure- and mixed cultivation]. | an acidophilic, aerobic and chemoheterotrophic bacterial strain teng-a was isolated from acidic environmental samples collected at sulfidic hot springs of tengchong county, yunnan province, china. cells of strain teng-a was rod-shaped (0.6-0.8 microm x 1.0 - 1.5 microm), gram-negative, motile with flagella. strain teng-a grew well at temperature of 29-33 degrees c and at ph of 3.0-4.0. it used a wide variety of organic compounds for growth, but did not use ferrous iron, elemental sulfur, thiosul ... | 2007 | 17552248 |
| microbial communities and geochemical dynamics in an extremely acidic, metal-rich stream at an abandoned sulfide mine (huelva, spain) underpinned by two functional primary production systems. | an extremely acidic (ph 2.5-2.75) metal-rich stream draining an abandoned mine in the iberian pyrite belt, spain, was ramified with stratified macroscopic gelatinous microbial growths ('acid streamers' or 'mats'). microbial communities of streamer/mat growths sampled at different depths, as well as those present in the stream water itself, were analysed using a combined biomolecular and cultivation-based approach. the oxygen-depleted mine water was dominated by the chemolithotrophic facultative ... | 2007 | 17564609 |
| geminicoccus roseus gen. nov., sp. nov., an aerobic phototrophic alphaproteobacterium isolated from a marine aquaculture biofilter. | a gram-negative, strictly aerobic, diplococcoid bacterium (strain d2-3(t)) was isolated from the biofilter of a recirculating marine aquaculture system. phylogenetic analysis of the 16s rrna gene sequence of d2-3(t) indicated that the new organism occupied a novel lineage within the alpha-1 subclass of proteobacteria and was related to the genera rhodothalassium, azospirillum, craurococcus, acidiphilium, and tistrella. the highest sequence similarity (90.8%) of the 16s rrna gene sequence of d2-3 ... | 2007 | 17643894 |
| the photosystem of rhodobacter sphaeroides assembles with zinc bacteriochlorophyll in a bchd (magnesium chelatase) mutant. | a rhodobacter sphaeroides bchd (magnesium chelatase) mutant was studied to determine the properties of its photosystem in the absence of bacteriochlorophyll (bchl). western blots of reaction center h, m, and l (rc h/m/l) proteins from mutant membranes showed levels of 12% rc h, 32% rc l, and 46% rc m relative to those of the wild type. tricine-sds-page revealed 52% light-harvesting complex alpha chain and 14% beta chain proteins compared to those of the wild type. pigment analysis of bchd cells ... | 2007 | 17910480 |
| prokaryotic community composition and ecology of floating macroscopic filaments from an extreme acidic environment, río tinto (sw, spain). | the prokaryotic diversity of macroscopic filaments located at the water surface in an extreme acidic environment, río tinto (sw, spain), has been analysed through denaturing gradient gel electrophoresis (dgge), cloning of 16s rrna genes and fluorescence in situ hybridization (fish). the dominant species present in the macrofilaments were acidithiobacillus ferrooxidans, leptospirillum ferrooxidans and acidiphilium spp., which represented the three main bacterial genera found in the water column o ... | 2007 | 17950555 |
| "bioshrouding": a novel approach for securing reactive mineral tailings. | a novel technique ("bioshrouding") for safeguarding highly reactive sulfidic mineral tailings deposits is proposed. in this, freshly milled wastes are colonised with ferric iron-reducing heterotrophic acidophilic bacteria that form biofilms on reactive mineral surfaces, thereby preventing or minimising colonisation by iron sulfide-oxidising chemolithotrophs such as acidithiobacillus ferrooxidans and leptospirillum spp. data from initial experiments showed that dissolution of pyrite could be redu ... | 2008 | 17975731 |
| evidence that the potential for dissimilatory ferric iron reduction is widespread among acidophilic heterotrophic bacteria. | nineteen characterized strains and isolates of acidophilic heterotrophic bacteria were screened for their abilities to catalyse the reductive dissolution of the ferric iron mineral schwertmannite, under oxygen-limiting conditions. acidocella facilis, acidobacterium capsulatum, and all of the acidiphilium, acidocella and acidobacterium-like isolates that grew in liquid cultures were able to reduce iron. in contrast, neither acidisphaera rubrifaciens nor three acidisphaera-like isolates tested wer ... | 2008 | 18081844 |
| ph gradient-induced heterogeneity of fe(iii)-reducing microorganisms in coal mining-associated lake sediments. | lakes formed because of coal mining are characterized by low ph and high concentrations of fe(ii) and sulfate. the anoxic sediment is often separated into an upper acidic zone (ph 3; zone i) with large amounts of reactive iron and a deeper slightly acidic zone (ph 5.5; zone iii) with smaller amounts of iron. in this study, the impact of ph on the fe(iii)-reducing activities in both of these sediment zones was investigated, and molecular analyses that elucidated the sediment microbial diversity w ... | 2008 | 18083864 |
| morphological changes in an acidophilic bacterium induced by heavy metals. | the acidiphilium strains inhabit acidic mine regions where they are subjected to occasional environmental stresses such as high and low temperatures, exposure to various heavy metals, etc. change in morphology is one of the strategies that bacteria adopt to cope with environmental stresses; however, no study on this aspect has been reported in the case of acidiphilium sp. this work is an attempt using the acidophilic heterotrophic bacterium acidiphilium symbioticum h8. it was observed that the m ... | 2008 | 18193380 |
| a microbial fuel cell operating at low ph using the acidophile acidiphilium cryptum. | for the first time, a microbial fuel cell has been developed using an acidophile, acidiphilium cryptum, as the anode biocatalyst. electricity production using its natural electron acceptor, iron, as the electron mediating agent at ph values < or =4.0 was demonstrated. accumulation of fe(iii) at the electrode, however, restricted current output. the combination of nitrilotriacetic acid and phenosafranin as electron mediators increased the power output to 12.7 mw/m(2) in a two-chamber air-sparged ... | 2008 | 18368296 |
| archaeal diversity in a fe-as rich acid mine drainage at carnoulès (france). | the acid waters (ph=2.73-3.4) that originate from the carnoulès mine tailings (france) are known for their very high concentrations of as (up to 10,000 mg l(-1)) and fe (up to 20,000 mg l(-1)). to analyze the composition of the archaeal community, (their temporal variation inside the tailing and spatial variations all along the reigous creek, which drains the site), seven 16s rrna gene libraries were constructed. clone analysis revealed that all the sequences were affiliated to the phylum euryar ... | 2008 | 18418543 |
| preferential use of an anode as an electron acceptor by an acidophilic bacterium in the presence of oxygen. | several anaerobic metal-reducing bacteria have been shown to be able to donate electrons directly to an electrode. this property is of great interest for microbial fuel cell development. to date, microbial fuel cell design requires avoiding o(2) diffusion from the cathodic compartment to the sensitive anodic compartment. here, we show that acidiphilium sp. strain 3.2 sup 5 cells that were isolated from an extreme acidic environment are able to colonize graphite felt electrodes. these bacterial e ... | 2008 | 18487393 |
| culturable and molecular phylogenetic diversity of microorganisms in an open-dumped, extremely acidic pb/zn mine tailings. | a combination of cultivation-based and molecular-based approaches was used to reveal the culturable and molecular diversity of the microbes inhabiting an open-dumped pb/zn mine tailings that was undergoing intensive acid generation (ph 1.9). culturable bacteria found in the extremely acidic mine tailings were acidithiobacillus ferrooxidans, leptospirillum ferriphilum, sulfobacillus thermotolerans and acidiphilium cryptum, where the number of acidophilic heterotrophs was ten times higher than tha ... | 2008 | 18512002 |
| a purple acidophilic di-ferric dna ligase from ferroplasma. | we describe here an extraordinary purple-colored dna ligase, ligfa, from the acidophilic ferrous iron-oxidizing archaeon ferroplasma acidiphilum, a di-ferric enzyme with an extremely low ph activity optimum. unlike any other dna ligase studied to date, ligfa contains two fe(3+)-tyrosinate centers and lacks any requirement for either mg(2+) or k(+) for activity. dna ligases from closest phylogenetic and ecophysiological relatives have normal ph optima (6.0-7.5), lack iron, and require mg(2+)/k(+) ... | 2008 | 18577594 |
| quantitative microbial community analysis of three different sulfidic mine tailing dumps generating acid mine drainage. | the microbial communities of three different sulfidic and acidic mine waste tailing dumps located in botswana, germany, and sweden were quantitatively analyzed using quantitative real-time pcr (q-pcr), fluorescence in situ hybridization (fish), catalyzed reporter deposition-fish (card-fish), sybr green ii direct counting, and the most probable number (mpn) cultivation technique. depth profiles of cell numbers showed that the compositions of the microbial communities are greatly different at the ... | 2008 | 18586975 |
| dissimilatory ferrous iron oxidation at a low ph: a novel trait identified in the bacterial subclass rubrobacteridae. | a novel iron-oxidizing acidophilic actinobacterium was isolated from spoil material at an abandoned copper mine. phylogenetic analysis placed the isolate within the rubrobacteridae subclass of the actinobacteria. its optimum temperature and ph for growth are 30-35 degrees c and ph 3.0, respectively. although it could catalyze the dissimilatory oxidation of ferrous iron, growth yields declined progressively in media containing ferrous iron concentrations >100 microm. the isolate, pa33, did not gr ... | 2008 | 18803673 |
| novosphingobium acidiphilum sp. nov., an acidophilic salt-sensitive bacterium isolated from the humic acid-rich lake grosse fuchskuhle. | a yellow- to orange-pigmented, gram-negative, rod-shaped, motile and non-spore-forming bacterium, strain fsw06-204d(t), was isolated from subsurface water of the acidic bog lake, lake grosse fuchskuhle (brandenburg, germany). optimum growth of this strain occurred over a ph range from 5.5 to 6.0 and the growth rate strongly decreased at ph values above 6.5. in addition, the strain exhibited a low tolerance towards nacl and grew only at a nacl concentration of up to 0.5 %. 16s rrna gene sequence ... | 2009 | 19196772 |
| microbial communities in acid mine drainage and their interaction with pyrite surface. | microbes such as acidithiobacillus ferrooxidans and leptospirillum ferrooxidans have been investigated a lot, because of their important role in acid mine drainage (amd) generation. in this article, the composition of microbial communities in two amd samples was studied. a culture-independent 16s rdna-based cloning approach, restriction fragment length polymorphism has been used. the interaction between microbes and natural pyrite specimen surface was researched by scanning electrode microscopy ... | 2009 | 19319595 |
| ferrimicrobium acidiphilum gen. nov., sp. nov. and ferrithrix thermotolerans gen. nov., sp. nov.: heterotrophic, iron-oxidizing, extremely acidophilic actinobacteria. | two novel extremely acidophilic, iron-oxidizing actinobacteria were isolated, one from a mine site in north wales, uk (isolate t23(t)), and the other from a geothermal site in yellowstone national park, wyoming, usa (y005(t)). these new actinobacteria belong to the subclass acidimicrobidae, and in contrast to the only other classified member of the subclass (acidimicrobium ferrooxidans), both isolates were obligate heterotrophs. the mine site isolate was mesophilic and grew as small rods, while ... | 2009 | 19406797 |
| versatile solidified nanofibrous cellulose-containing media for growth of extremophiles. | solidified media that employ a porous matrix of nanofibrous cellulose are described. the physicochemical stability of the porous structure allows the development of solidified media that can support the growth of extremophiles, such as acidophilic acidiphilium, alkaliphilic bacillus, thermophilic geobacillus and thermus, alkalithermophilic bacillus, and acidothermophilic sulfolobus microbes. the cellulose-supported media have several advantages over agar- and gellan gum-derived media, including ... | 2009 | 19411423 |
| extraction of extracellular polymeric substances from the acidophilic bacterium acidiphilium 3.2sup(5). | extraction of extracellular polymeric substances (eps) from acidiphilium 3.2sup(5) was investigated using five methods: edta, naoh, ion exchange resin, heating and centrifugation. the bacterium studied presents promising application in microbial fuel cells (mfcs). the degree of cellular lysis provoked by each method was determined by uv-visible spectroscopy of cultures before and after eps extraction. in addition, two electron microscopy techniques (tem and sem) were employed to determine the de ... | 2009 | 19474490 |
| microbiological monitoring of acid mine drainage treatment systems and aquatic surroundings using real-time pcr. | in general, acid mine drainage (amd) causes low ph and high metal concentrations in mining areas and surroundings. the aim of this research was to achieve microbiological monitoring for amd and to assess whether mine water outflows have any ecological effects on the aqueous ecosystem receiving effluents from different types of treatment system. the water quality of aquatic sample was analyzed and the molecular biological diversity of the samples was assessed using 16s rrna methods, which were im ... | 2009 | 19494446 |