In the course of our screening for dibenzo-p-dioxin-utilizing bacteria, a Sphingomonas sp. strain was isolated from enrichment cultures inoculated with water samples river Elbe. The isolate grew both biaryl ethers dibenzo-p-dioxin and dibenzofuran (DF) as sole sources carbon energy, showing doubling times about 8 5 h, respectively. Biodegradation two aromatic compounds initially proceeded after an oxygenolytic attack at angular position adjacent to ether bridge, producing...

Two Pseudomonas sp. strains, capable of growth on chlorinated benzenes as the sole source carbon and energy, were isolated by selective enrichment from soil samples an industrial waste deposit. Strain PS12 grew monochlorobenzene, all three isomeric dichlorobenzenes, 1,2,4-trichlorobenzene (1,2,4-TCB). PS14 additionally used 1,2,4,5-tetrachlorobenzene (1,2,4,5-TeCB). During these compounds both strains released stoichiometric amounts chloride ions. The first steps catabolism 1,2,4-TCB...

A Pseudomonas sp. strain, HH69, and a mixed culture, designated HH27, were isolated by selective enrichment from soil samples. The pure strain the culture grew aerobically on dibenzofuran as sole source of carbon energy. Degradation proceeded via salicylic acid which was branched into gentisic catechol pathway. Both accumulated in medium HH69. acids slowly metabolized after growth ceased. enzymes responsible for their metabolism showed relatively low activities. Besides above-mentioned...

Trees belonging to the genus Populus are often used for phytoremediation due their deep root formation, fast growth and high transpiration rates. Here, we study capacity of transgenic hybrid aspen (Populus tremula x tremuloides var. Etropole) which expresses bacterial nitroreductase gene, pnrA, tolerate take-up greater amounts toxic recalcitrant explosive, 2,4,6-trinitrotoluene (TNT) from contaminated waters soil. Transgenic up 57 mg TNT/L in hydroponic media more than 1000 TNT/kg soil,...

The bacterium Sphingomonas sp. strain SS3, which utilizes diphenyl ether and its 4-fluoro, 4-chloro, (to a considerably lesser extent) 4-bromo derivatives as sole sources of carbon energy, was enriched from soil samples an industrial waste deposit. showed cometabolic activities toward all other isomeric monohalogenated ethers. During degradation in batch culture experiments, phenol catechol were produced intermediates then channeled into the 3-oxoadipate pathway. initial step follows...

Although much information on metabolic pathways within individual organisms is available, little known about the operating in natural communities which extensive sharing of nutritional resources rule. In order to analyse such a consortium pathway, we have investigated flow 4‐chlorosalicylate as carbon substrate simple chemostat microbial community using 13 C‐labelled metabolites and isotopic ratio mass spectrometric analysis label enrichment immunocaptured member populations community. A...

The ability of the dibenzofuran- and dibenzo-p-dioxin-mineralizing bacterium Sphingomonas sp. strain RW1 (R.-M. Wittich, H. Wilkes, V. Sinnwell, W. Francke, P. Fortnagel, Appl. Environ. Microbiol. 58:1005-1010, 1992) to oxidize chlorinated derivatives dibenzofuran dibenzo-p-dioxin was analyzed. Strain degraded several mono- dichlorinated dibenzofurans dibenzo-p-dioxins, but it did not degrade more highly congeners. Most dibenzo-p-dioxins investigated in this study were corresponding...

Chloroaromatics, a major class of industrial pollutants, may be oxidatively metabolized to chlorocatechols by soil and water microorganisms that have evolved catabolic activities toward these xenobiotics. We show here 4-chlorocatechol can further transformed enzymes the ubiquitous 3-oxoadipate pathway. However, whereas chloromuconate cycloisomerases catalyze dechlorination 3-chloro-cis,cis-muconate form cis-dienelactone, muconate novel reaction, i.e. concomitant decarboxylation...

The bacterium Sphingomonas sp. strain SS33, obtained from parent diphenyl ether-mineralizing SS3 (S. Schmidt, R.-M. Wittich, D. Erdmann, H. Wilkes, W. Francke, and P. Fortnagel, Appl. Environ. Microbiol. 58:2744-2750, 1992) after several weeks of adaptation on 4,4'-difluorodiphenyl ether as the new target compound, also utilized 4,4'-dichlorodiphenyl for growth. Intermediary halocatechols were mineralized via ortho pathway by type I enzymes. 4,4'-Dibromodiphenyl was not used a carbon source...

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 as growth substrate. Regioselective 1,2-dioxygenation effected desulfonation and catabolism 5-sulfosalicylic (5SS), which used the sole carbon source. 5SS-grown cells exhibited high gentisate 1,2-dioxygenase activity. Neither 5SS- nor gentisate-grown oxidized 2,6NDS; therefore, 2,6NDS or early metabolite must...

Summary There has been a growing interest in the degradation of 2,4,6‐trinitrotoluene (TNT) over last decade, ever since its removal from polluted sites was declared an international environmental priority. Certain aerobic and anaerobic microorganisms are capable using TNT as N source, although very few studies have proven mineralization this compound. An unexpected observation our laboratory led us to discover that certain Escherichia coli bench strains multiple enzymes attack TNT. One NemA...

Summary Pseudomonas putida KT2440 grows in M9 minimal medium with glucose the presence of 2,4,6‐trinitrotoluene (TNT) at a similar rate than absence TNT, although global transcriptional analysis using DNA microarrays revealed that TNT exerts some stress. Response to stress is regulated level, as significant changes level expression 65 genes were observed. Of these genes, 39 appeared upregulated, and 26 downregulated. The identity upregulated suggests P. uses two kinds strategies overcome...

ABSTRACT The bacterium Sphingomonas sp. strain RW1 is able to use dibenzo- p -dioxin, dibenzofuran, and several hydroxylated derivatives as sole sources of carbon energy. We have determined analyzed the nucleic acid sequence a 9,997-bp Hin dIII fragment downstream cistrons dxnA1A2 , which encode dioxygenase component initial system corresponding catabolic pathways. This contains 10 colinear open reading frames (ORFs), apparently organized in one compact operon. enzymatic activities some...

ABSTRACT A 4,103-bp long DNA fragment containing the structural gene of a gentisate 1,2-dioxygenase (EC 1.13.11.4 ), gtdA , from Sphingomonas sp. strain RW5 was cloned and sequenced. The encodes 350-amino-acid polypeptide with predicted size 38.85 kDa. Comparison product protein sequences in databases, including those intradiol or extradiol ring-cleaving dioxygenases, revealed no significant homology except for low similarity (27%) to 1-hydroxy-2-naphthoate dioxygenase ( phdI ) phenanthrene...

ABSTRACT Bacterial strain LW1, which belongs to the family Comamonadaceae , utilizes 1-chloro-4-nitrobenzene (1C4NB) as a sole source of carbon, nitrogen, and energy. Suspensions 1C4NB-grown cells removed 1C4NB from culture fluids, there was concomitant release ammonia chloride. Under anaerobic conditions LW1 transformed into product identified 2-amino-5-chlorophenol by 1 H 13 C nuclear magnetic resonance (NMR) spectroscopy mass spectrometry. This transformation indicated that partial...

ABSTRACT Pseudomonas chlororaphis RW71 mineralized 1,2,3,4-tetrachlorobenzene, a highly recalcitrant pollutant hitherto not known to be degraded by pure cultures, as sole source of carbon and energy, thereby releasing stoichiometric amounts chloride. The transient excretion tetrachlorocatechol in the early growth phase suggests an initial attack dioxygenase form corresponding dihydrodiol which rearomatizes catechol. activity chlorocatechol 1,2-dioxygenase crude cell extracts was found...

A rapid decline in cell viability of different PCB-metabolizing organisms was observed soil microcosms amended with 4-chlorobiphenyl. The toxic effect could not be attributed to 4-chlorobiphenyl but due a compound formed from the transformation by natural microflora. Potential metabolites 4-chlorobiphenyl, 4-chlorobenzoate and 4-chlorocatechol, caused similar effects. We tested hypothesis that effects are formation protoanemonin, plant-derived antibiotic, which is microorganisms has been...

Pseudomonas putida uses l-lysine as the sole carbon and nitrogen source which preferentially requires its metabolism through two parallel pathways. In one of pathways delta-aminovalerate is key metabolite, whereas in other racemized to d-lysine, l-pipecolate alpha-aminoadipate are metabolites. All genes enzymes involved d-lysine pathway, except for those conversion into Delta(1)-piperideine-2-carboxylate, have been identified previously (30). this study we report that...