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1.
Arch Microbiol ; 172(1): 45-50, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10398751

RESUMO

Cloned luciferase-encoding operons were transferred by conjugation to a natural isolate of the ammonia-oxidizing bacterial strain Nitrosomonas sp. RST41-3, thereby establishing conjugation as a tool for gene transfer into Nitrosomonas strains. Luminescence was dependent on the pH of the medium and the concentration of the substrate ammonium chloride. Moreover, the luminescence of the transconjugants was reduced immediately by micromolar concentrations of nitrapyrin and allylthiourea, which are specific inhibitors of nitrification. Our results indicate that luminescent Nitrosomonas strains may be useful as a probe to detect nitrification conditions in the natural environment as well as in sewage plants.


Assuntos
Medições Luminescentes , Nitrosomonas/fisiologia , Transfecção/métodos , Cloreto de Amônio/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Meios de Cultura , Técnicas de Transferência de Genes , Genes Bacterianos/genética , Concentração de Íons de Hidrogênio , Luciferases/genética , Nitritos/metabolismo , Nitrosomonas/genética , Picolinas/farmacologia , Tioureia/análogos & derivados , Tioureia/farmacologia
2.
Chemosphere ; 29(1): 81-8, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8044636

RESUMO

Six bacterial strains able to degrade aerobically 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) were isolated. The bacteria used PBTC as sole source of phosphorus in the presence of an alternative source of carbon. The microorganisms were taken from various ecosystems, e.g. river water, river sediment and activated sludge. PBTC up to a concentration of 1 mM (270 mg/l) was completely degraded by a defined mixed culture.


Assuntos
Bactérias/metabolismo , Compostos Organofosforados/metabolismo , Microbiologia da Água , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Carbono/metabolismo , Ecossistema , Compostos Organofosforados/análise
3.
FEMS Microbiol Lett ; 53(1-2): 205-9, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2612886

RESUMO

Two dibenzofuran degrading bacteria, Brevibacterium strain DPO 1361 and strain DPO 220, were found to utilize fluorene as sole source of carbon and energy. Cells which were grown on dibenzofuran, transformed fluorene into a number of products. For five of the seven metabolites isolated, the structure could be established unequivocally. Accumulation of one metabolite, 1,10-dihydroxy-1,10-dihydrofluoren-9-one, indicated the presence of a novel type of dioxygenase, attacking polynuclear aromatic systems in the unusual angular position. Debenzofuran degradation is proposed to likewise proceed via initial angular dioxygenation. One aryl oxygen ether bond, which normally is extremely stable, is thus transformed to a hemiacetal. After spontaneous cleavage and subsequent rearomatization by dehydration, 2,2',3-trihydroxybiphenyl [3-(2-hydroxyphenyl)-catechol] thus results as the immediate product of the first enzymatic reaction in the degradation sequence.


Assuntos
Benzofuranos/metabolismo , Brevibacterium/metabolismo , Fluorenos/metabolismo , Biodegradação Ambiental , Fenômenos Químicos , Físico-Química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
4.
FEMS Microbiol Lett ; 49(2-3): 233-8, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2744419

RESUMO

Dibenzofuran degrading bacteria were enriched from various environmental sources. A mutualistic mixed culture of strain DPO 220 and strain DPO 230 was characterized. Strain DPO 220 alone showed limited growth with dibenzofuran as sole source of carbon and energy (td greater than or equal to 4.5 h). A labile degradation product, C12H10O5, and salicylate were isolated from the culture fluid. Salicylate was found to be a central intermediate of DBF-degradation. Strain DPO 220 co-metabolized a wide range of anellated aromatics as well as heteroaromatics. High rates of co-oxidation of dibenzodioxin demonstrate analogue-enrichment to be a powerful technique for selecting enzymatic activities for otherwise non-degradable substrates.


Assuntos
Bactérias/metabolismo , Benzofuranos/metabolismo , Dioxinas/metabolismo , Bactérias/isolamento & purificação , Biodegradação Ambiental , Salicilatos/metabolismo , Ácido Salicílico
5.
Appl Environ Microbiol ; 54(7): 1842-7, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3415238

RESUMO

A naphthalene-2,6-disulfonic acid (2,6NDS)-degrading Moraxella strain was isolated from an industrial sewage plant. This culture could also be adapted to naphthalene-1,6-disulfonic acid as growth substrate. Regioselective 1,2-dioxygenation effected desulfonation and catabolism to 5-sulfosalicylic acid (5SS), which also could be used as the sole carbon source. 5SS-grown cells exhibited high gentisate 1,2-dioxygenase activity. Neither 5SS- nor gentisate-grown cells oxidized 2,6NDS; therefore, 2,6NDS or an early metabolite must serve as an inducer of the initial catabolic enzyme(s).


Assuntos
Moraxella/metabolismo , Naftalenossulfonatos/metabolismo , Benzenossulfonatos , Biodegradação Ambiental , Catálise , Meios de Cultura , Gentisatos/metabolismo , Moraxella/isolamento & purificação , Oxirredução , Salicilatos/metabolismo , Enxofre/metabolismo
6.
Appl Environ Microbiol ; 52(5): 1195-202, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3789715

RESUMO

A 6-aminonaphthalene-2-sulfonic acid (6A2NS)-degrading mixed bacterial community was isolated from a sample of river Elbe water. The complete degradation of this xenobiotic compound may be described by a mutualistic interaction of two Pseudomonas strains isolated from this culture. One strain, BN6, could also grow on 6A2NS in monoculture, however, with accumulation of black polymers. This organism effected the initial conversion of 6A2NS into 5-aminosalicylate (5AS) through regioselective attack of the naphthalene skeleton in the 1,2-position. 5AS was totally degraded by another member of the community, strain BN9. After prolonged adaptation of strain BN6 to growth on 6A2NS, this organism readily converted all naphthalene-2-sulfonates with OH- or NH2-substituents in the 5-, 6-, 7-, or 8-position. The corresponding hydroxy- or aminosalicylates were excreted in stoichiometric amounts, with the exception that the metabolite from 5A2NS oxidation was not identical with 6AS.


Assuntos
Naftalenossulfonatos/metabolismo , Naftóis/metabolismo , Pseudomonas/metabolismo , Microbiologia da Água , Ácidos Aminossalicílicos/metabolismo , Biodegradação Ambiental , Meios de Cultura , Água Doce , Mesalamina , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/isolamento & purificação , Salicilatos/metabolismo
7.
Arch Microbiol ; 114(1): 25-33, 1977 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-907425

RESUMO

4-(Methylmercapto)-phenol (MMP) and 4-(methylsulfinyl)-phenol (MSP) are oxidized by the soil isolate Nocardia spec. DSM 43251, which is closely related to Nocardia calcarea. The rate of degradation depends on the capability of a substrate to support growth and is strongly enhanced in the presence of a second carbon source under the conditions of cooxidation. MMP and MSP are cometabolized by hydroxylation of the benzene ring with the formation of the substituted catechol following by ring cleavage between carbon atoms 2 and 3 ("meta" fission) to give 2-hydroxy-5-methylmercapto-or-2-hydroxy-5-methylsulfinylmuconic semialdehyde. Oxidation of MMP to MSP represents a bypath of MMP-oxidation. The intermediates were identified on the basis of their physical properties. The enzymes responsible for the metabolism of MMP and MSP are induced by growth with MMP or MSP, but not with glucose. MMP-and MSP-induced cells catalyze the oxidation of a variety of substituted phenols. This indicates a rather low substrate specificity of the enzymes induced by MMP and MSP.


Assuntos
Nocardia/metabolismo , Compostos Organomercúricos/metabolismo , Fenóis/metabolismo , Microbiologia do Solo , Acetatos/metabolismo , Ácido Ascórbico/metabolismo , Biodegradação Ambiental , Catecóis , Fumaratos/metabolismo , Nocardia/enzimologia , Nocardia/crescimento & desenvolvimento , Oxirredução , Oxigenases/metabolismo , Piruvatos/metabolismo , Succinatos/metabolismo
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