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1.
Science ; 215(4539): 1505-7, 1982 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-17788676

RESUMO

Mixed inoculums of microorganisms from Chesapeake Bay sediments transformed inorganic tin (SnCl(4) . 5H(2)O) to organotin compounds. Dimethyltin and trimethyltin species were identified as products by gas chromatography-mass spectrometry. Methylated tin species were not observed in sterile controls or in poisoned controls. Thus, estuarine microorganisms have the potential for transforming tin to toxic organotins and for mobilizing tin in the ecosystem.

2.
J Inorg Biochem ; 80(1-2): 17-20, 2000 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-10885458

RESUMO

The development of the understanding of the co-ordination chemistry and the properties of Amavadin, the chemical form in which vanadium is accumulated by the Amanita genus of mushrooms, is reviewed.


Assuntos
Amanita/química , Vanádio/química , Espectroscopia de Ressonância de Spin Eletrônica , Isomerismo , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectrofotometria Infravermelho
7.
Appl Microbiol ; 17(2): 227-31, 1969 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16349836

RESUMO

Four, open-cell, ester-base polyurethane foams were examined for their effect on growth of fuel-utilizing organisms in jet fuel-water systems. Three foams contained a potential biocide, tetraethylthiuram E (0.66%), sodium omadine (0.07%), or zinc omadine (0.07%), all w/v. These were compared with a control foam which did not contain an additive. Each foam was examined in fuel-water systems containing JP-4 fuel, JP-4 fuel plus 0.1% anti-icing additive (AIA), or JP-5 fuel. Pure cultures of a fuel-grown bacterium, Pseudomonas aeruginosa, and of a fuel-grown fungus, Hormodendrum (Cladosporium) sp., served as test organisms. In control cultures without foam and in cultures containing control foam, P. aeruginosa achieved maximum stationary-phase populations of approximately 10 viable cells per ml, and Hormodendrum sp. produced an extensive mycelial mat. In the three fuel systems examined, tetraethylthiuram E- and sodium omadine-containing foams had little effect on growth of the bacterium; foam with zinc omadine decreased the rate of bacterial growth but had little effect on total populations. Tetraethylthiuram E decreased the rate of fungal growth and showed its greatest effect in JP-4 plus AIA. Foam with sodium omadine or zinc omadine markedly decreased fungal growth in all three fuel systems. The data suggest that either sodium omadine or zinc omadine in polyurethane foam may be a useful antifungal agent; and that tetraethylthiuram E and AIA could exert a synergistic effect, particularly at AIA concentrations which have been reported to occur in some field situations.

8.
Appl Environ Microbiol ; 52(3): 562-6, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3094450

RESUMO

Pure cultures of Escherichia coli and Streptococcus faecalis and environmental water samples were examined for the possibility that pollution involving organotin compounds could decrease the values for indicator organisms when standard methods were applied to the analysis of water samples. (CH3)2SnCl2 and (CH3)3SnCl decreased viable counts at about 10 to 100 mg of Sn liter-1 (8.4 X 10(-5) to 8.4 X 10(-4) mol of Sn liter-1), and tributyltin chloride was effective at about 0.1 to 1.0 mg of Sn liter-1 (8.4 X 10(-7) to 8.4 X 10(-6) mol of Sn liter-1. These concentrations, particularly for the methyltin compounds, are greater than the concentrations reported to date for these compounds in aquatic ecosystems. Thus, organotin compounds alone would not be likely to cause reductions in counts of indicator organisms measured by standard methods. However, it is suggested that, when combined with other environmental stressors or upon long exposure, organotins such as butyltins may contribute to the injury of indicator organisms.


Assuntos
Enterococcus faecalis/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Compostos Orgânicos de Estanho/farmacologia , Microbiologia da Água , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Compostos de Trialquitina/farmacologia , Poluição Química da Água
9.
Appl Environ Microbiol ; 41(2): 466-71, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16345719

RESUMO

Sediment and water samples from nine stations in Chesapeake Bay were examined for tin content and for microbial populations resistant to inorganic tin (75 mg of Sn liter as SnCl(4).5H(2)O) or to the organotin compound dimethyltin chloride [15 mg of Sn liter as (CH(3))(2)SnCl(2)]. Tin concentrations in sediments were higher (3.0 to 7.9 mg kg) at sites impacted by human activity than at open water sites (0.8 to 0.9 mg kg), and they were very high (239.6 mg kg) in Baltimore Harbor, which is impacted by both shipping and heavy industry. Inorganic tin (75 mg Sn liter) in agar medium significantly decreased viable counts, but its toxicity was markedly reduced in liquid medium; it was not toxic in medium solidified with silica gel. Addition of SnCl(4).5H(2)O to these media produced a tin precipitate which was not involved in the metal's toxicity. The data suggest that a soluble tin-agar complex which is toxic to cells is formed in agar medium. Thus, the toxicity of tin depends more on the chemical species than on the metal concentration in the medium. All sites in Chesapeake Bay contained organisms resistant to tin. The microbial flora was more sensitive to (CH(3))(2)SnCl(2) than to SnCl(4).5H(2)O. The elevated level of tin-resistant microorganisms in some aeas not containing unusually high tin concentrations suggests that factors other than tin may participate in the selection for a tin-tolerant microbial flora.

10.
Appl Environ Microbiol ; 45(2): 706-10, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16346219

RESUMO

A replica plating method was developed for detecting and enumerating phenanthrene-degrading microorganisms. The method is designed to discriminate between aquatic organisms that utilize phenanthrene as the sole carbon and energy source and organisms that cometabolize phenanthrene. The method was used to demonstrate that phenanthrene utilizers and phenanthrene cometabolizers coexist in estuarine sediments.

11.
Appl Microbiol ; 15(2): 411-6, 1967 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6029836

RESUMO

Seventy-two samples from jet aircraft fuel systems were examined for microbial contamination. Ten contaminated samples yielded 43 microorganisms which were classified into nine genera of bacteria and three genera of fungi. The predominant types, comprising about 37% of the isolated cultures, were identified as Bacillus spp. The remaining cultures were distributed among 11 genera, each of which represented 2 to 9% of the total isolates. Four cultures could not be assigned to a genus on the basis of the diagnostic criteria used. Only five isolates, in the genera Pseudomonas and Hormodendrum (Cladosporium), grew abundantly in a mineral salts solution with JP-4 fuel as the sole source of carbon. The presence of fuel utilizers in a fuel system may be a better index to potential problems that have been correlated with microbial contamination than the presence of aerobic sporeforming bacilli.


Assuntos
Aviação , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Petróleo , Bacillus/isolamento & purificação , Bactérias/metabolismo , Combustíveis Fósseis , Fungos/metabolismo
12.
J Bacteriol ; 96(1): 234-41, 1968 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-5663569

RESUMO

In addition to canthaxanthin, seven pigment fractions were isolated from Micrococcus roseus. They were purified by solvent partitioning and by column and thin-layer chromatography. Visible absorption spectra, chromatographic behavior, and partition coefficients of the pigments and derivatives prepared from the pigments were used in characterizing them. Both alpha- and beta-carotene derivatives were present. The structure of one pigment was suggested as phoenicoxanthin (3-hydroxy-4,4'-diketo-beta-carotene). Four other pigments were tentatively characterized as a dihydroxy-3,4-dehydro-alpha-carotene, a dihydroxy-alpha-carotene, a diketo-alpha-carotene, and a polyhydroxy-beta-carotene. Two pigments were isolated in trace amounts and could not be characterized. All the pigments studied were isolated as mixtures of cis-trans isomers and all except the diketo-alpha-carotene were isolated as esters from M. roseus. Quantitation of the pigments showed that canthaxanthin (4,4'-diketo-beta-carotene) represented 85% of the pigment recovered from extracts. Three of the other pigments contributed a significant proportion of the remaining pigments, whereas the other four were present in only small amounts. beta-Carotene derivatives comprised 96% and alpha-carotene derivatives 4% of the pigments recovered from extracts.


Assuntos
Carotenoides/análise , Micrococcus/análise , Técnicas de Química Analítica , Cromatografia em Camada Fina , Espectrofotometria
13.
J Bacteriol ; 112(3): 1422-4, 1972 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4640507

RESUMO

The carotenoid 4'-hydroxyechinenone (4'-hydroxy-beta, beta-carotene-4-one) was isolated from Micrococcus roseus. It is proposed as an intermediate between echinenone and canthaxanthin.


Assuntos
Carotenoides/isolamento & purificação , Micrococcus/análise , Boroidretos , Carotenoides/análise , Fenômenos Químicos , Química , Cromatografia em Gel , Cromatografia em Camada Fina , Análise Espectral
14.
Can J Microbiol ; 21(8): 1205-10, 1975 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1172456

RESUMO

Cladosporium resinae was grown on glucose, on n-dodecane, and on n-hexadecane. Total lipid was greatest in dodecane-grown cells and least in hexadecane-grown cells, while glucose-grown cells contained the most phospholipid and hexadecane-grown cells contained the least. Cells from all three media contained phosphatidylethanolamine and phosphatidylcholine as their major phospholipids, with lesser amounts of phosphatidylserine and traces of a cardiolipin-like compound. The major fatty acids associated with each phospholipid were palmitic acid and one or more 18-carbon unsaturated fatty acids. There was no correlation between n-alkane growth substrate and fatty acyl components of cellular phospholipids.


Assuntos
Alcanos/metabolismo , Cladosporium/metabolismo , Glucose/metabolismo , Fungos Mitospóricos/metabolismo , Fosfolipídeos/biossíntese , Cardiolipinas/biossíntese , Ácidos Graxos/biossíntese , Ácidos Palmíticos/biossíntese , Fosfatidilcolinas/biossíntese , Fosfatidiletanolaminas/biossíntese , Fosfatidilserinas/biossíntese
15.
Appl Microbiol ; 29(5): 604-9, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-238469

RESUMO

Cladosporium (Amorphotheca) resinae was grown in shake culture on glucose, n-dodecane, or n-hexadecane. Growth was most rapid on glucose, and more acid accumulated in the medium than in n-alkane-grown cultures. Neutral lipid was the major lipid fraction and triglycerides were the only extracellular neutral lipids detected. Dodecanoic (lauir) acid was the predominant fatty acid (greater than 60%) in neutral lipids from all three media, with lesser amounts of tetradecanoic, hexadecanoic, and octadecanoic acids. Extracellular phospholipids identified were phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine, and cardiolipin or a cardiolipin-like compound. Phospholipids from all three media contained dodecanoic acid as their principle fatty acid. Dodecanoic acid was the only extracellular free fatty acid detected. Glucose medium contained acetic, glyoxylic, and glycolic acids and an unidentified organic acid which may contribute to the lower pH in cultures after growth on glucose. In all classes of extracellular lipids the fatty acids do not correspond to the fatty acids previously determined to be associated with cellular lipids. Moreover, the fatty acids of extracellular lipids do not reflect the chain length of the n-alkane growth substrate.


Assuntos
Alcanos/metabolismo , Cladosporium/análise , Glucose/metabolismo , Lipídeos/análise , Fungos Mitospóricos/análise , Acetatos/análise , Cromatografia Gasosa , Cromatografia em Papel , Cromatografia em Camada Fina , Cladosporium/crescimento & desenvolvimento , Cladosporium/metabolismo , Ácidos Graxos não Esterificados/análise , Glicolatos/análise , Glioxilatos/análise , Concentração de Íons de Hidrogênio , Ácidos Láuricos/análise , Lipídeos/biossíntese , Fosfolipídeos/análise , Triglicerídeos/análise
16.
Can J Microbiol ; 27(4): 421-5, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7237286

RESUMO

Micrococcus roseus forms bicyclic keto-carotenoids. The effects of nicotine, piperonyl butoxide, and 2-(4-chlorophenylthio)-triethylamine hydrochloride (CPTA) were studied with regard to their ability to selectively inhibit carotenogenesis in the organism. Nicotine caused accumulation of beta-zeacarotene; piperonyl butoxide caused accumulation of phytoene and traces of phytofluene, zeta-carotene, and beta-zeacarotene. In both cases canthaxanthin biosynthesis was inhibited. CPTA inhibited canthaxanthin synthesis and caused accumulation of beta-zeacarotene and gamma-carotene and their mono- and di-hydroxy derivatives. Regardless of the inhibitor used, canthaxanthin was the major colored carotenoid biosynthesized. The expected precursors of carotenoid cyclization, neurosporene and (or) lycopene, were not detected in CPTA- or nicotine-inhibited cultures. Therefore, carotenoid cyclization in M. roseus does not involve neurosporene or lycopene and must occur early in carotene biosynthesis, prior to the formation of beta-zeacarotene, zeta-Carotene is proposed as the cyclization substrate and beta-zeacarotene as the substrate for oxygen insertion.


Assuntos
Carotenoides/biossíntese , Etilaminas , Micrococcus/metabolismo , Carotenoides/metabolismo , Licopeno , Micrococcus/efeitos dos fármacos , Nicotina/farmacologia , Fenetilaminas/farmacologia , Butóxido de Piperonila/farmacologia , Sulfetos/farmacologia
17.
J Bacteriol ; 98(1): 16-22, 1969 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4976464

RESUMO

Lipids were extracted from cells of Pseudomonas aeruginosa grown on a pure hydrocarbon (tridecane), mixed hydrocarbons (JP-4 jet fuel), and on Trypticase Soy Broth. Total lipids produced from each substrate represented from 7.1 to 8.2% of cellular dry weight, of which 5.0 to 6.4% were obtained before cellular hydrolysis (free lipids) and 1.7 to 2.0% were extracted after cellular hydrolysis (bound lipids). Free lipids from cells grown on each medium were separated into four fractions by thin-layer chromatography. All fractions were present in cells from each type of medium, and the "neutral fraction" constituted the largest fraction. The fatty acid composition of free lipids was determined by gas-liquid chromatography. Cells grown on each medium contained saturated and unsaturated C(14) to C(20) fatty acids. Trace amounts of C(13) fatty acids were found in tridecane-grown cells. Saturated C(16) and C(18) were the major acids present in all cells. Quantitative differences were found in fatty acids produced on the three media, but specific correlations between substrate carbon sources and fatty acid content of cells were not evident. Tridecane-grown cells contained only traces of C(13) acid and small amounts of C(15) and C(17) acids, suggesting that the organism's fatty acids were derived from de novo synthesis rather than by direct incorporation of the hydrocarbon.


Assuntos
Meios de Cultura , Hidrocarbonetos/metabolismo , Lipídeos/análise , Pseudomonas aeruginosa/metabolismo , Alcanos/metabolismo , Cromatografia Gasosa , Cromatografia em Camada Fina , Ácidos Graxos/análise , Combustíveis Fósseis , Lipídeos/biossíntese , Pseudomonas aeruginosa/análise
18.
J Bacteriol ; 108(2): 777-81, 1971 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-5166858

RESUMO

Cladosporium resinae was grown in submerged cultures on glucose; on Jet-A commercial aviation fuel; and on a series of n-alkanes, n-decane through n-tetradecane. Cell yield was greatest on glucose and least on Jet-A; n-alkanes were intermediate. Among n-alkanes cell yield decreased as chain length increased, except for n-dodecane, which supported less growth than n-tridecane or n-tetradecane. The total fatty acids of stationary-phase cells were analyzed by gas-liquid chromatography. In all cases the predominant fatty acids were 16:0, 18:1, and 18:2. The fatty acid composition of glucose-grown cells was similar to that of hydrocarbon-grown cells. Cells grown on n-tridecane or n-tetradecane yielded small amounts of acids homologous to the carbon source, but a similar correlation was not noted for n-decane, n-undecane, or n-dodecane. Cells grown on n-undecane or n-tridecane contained more odd-carbon fatty acids than cells grown on the other substrates, and the effect was more pronounced in n-tridecane-grown cells. Thus, the fatty acids of this organism are derived chiefly from de novo synthesis rather than from direct incorporation of oxidized hydrocarbons. The extent of direct incorporation increases as the chain length of the hydrocarbon growth substrate is increased.


Assuntos
Alcanos/metabolismo , Ácidos Graxos/análise , Glucose/metabolismo , Fungos Mitospóricos/análise , Petróleo/metabolismo , Cromatografia Gasosa , Meios de Cultura , Ésteres/análise , Ácidos Graxos Essenciais/análise , Combustíveis Fósseis , Concentração de Íons de Hidrogênio , Querosene/metabolismo , Fungos Mitospóricos/crescimento & desenvolvimento , Fungos Mitospóricos/metabolismo
19.
J Bacteriol ; 104(1): 272-4, 1970 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-5473895

RESUMO

An orange carotenoid from Micrococcus roseus was purified by solvent partitioning followed by column and thin-layer chromatography. Absorption spectra, chromatographic mobility, and partition coefficient suggested that the pigment was echinenone (4-keto-beta-carotene). Reduction yielded a pigment with the spectral and polar properties of isocryptoxanthin (4-hydroxy-beta-carotene), the expected product. The orange pigment and its reduction product co-chromatographed with the respective authentic pigments, confirming the original pigment as echinenone. To our knowledge echinenone has not been identified previously as a bacterial pigment.


Assuntos
Carotenoides/isolamento & purificação , Micrococcus/análise , Carotenoides/classificação , Carotenoides/metabolismo , Cromatografia em Gel , Cromatografia em Camada Fina , Micrococcus/metabolismo , Análise Espectral
20.
J Bacteriol ; 115(2): 635-9, 1973 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4146874

RESUMO

Pathways of initial oxidation of n-alkanes were examined in two strains of Cladosporium resinae. Cells grow on dodecane and hexadecane and their primary alcohol and monoic acid derivatives. The homologous aldehydes do not support growth but are oxidized by intact cells and by cell-free preparations. Hexane and its derivatives support little or no growth, but cell extracts oxidize hexane, hexanol, and hexanal. Alkane oxidation by extracts is stimulated by reduced nicotinamide adenine dinucleotide (phosphate). Alcohol and aldehyde oxidation are stimulated by nicotinamide adenine dinucleotide (phosphate), and reduced coenzymes accumulate in the presence of cyanide or azide. Extracts supplied with (14)C-hexadecane convert it to the alcohol, aldehyde, and acid. Therefore, the major pathway for initial oxidation of n-alkanes is via the primary alcohol, aldehyde, and monoic acid, and the system can act on short-, intermediate-, and long-chain substrates. Thus, filamentous fungi appear to oxidize n-alkanes by pathways similar to those used by bacteria and yeasts.


Assuntos
Alcanos/metabolismo , Fungos Mitospóricos/metabolismo , Álcoois/metabolismo , Aldeídos/metabolismo , Isótopos de Carbono , Sistema Livre de Células , Cromatografia em Camada Fina , Glucose/metabolismo , Glutamatos/metabolismo , Fungos Mitospóricos/crescimento & desenvolvimento , NAD/farmacologia , NADP/farmacologia , Oxirredução , Consumo de Oxigênio , Temperatura
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