Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Sphingomonas”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed1999

Phylogeny of Sphingomonas species that degrade pentachlorophenol.

Four pentachlorophenol (PCP)-degrading bacteria isolated from geographically diverse areas have been examined in detail as regards their physiology and phylogeny. According to traditional biochemical methods, these strains had been classified as members of the genera Arthrobacter, Flavobacterium, Pseudomonas, and Sphingomonas. The PCP degradation pathway has been studied extensively in Sphingomonas (Flavobacterium) sp strain ATCC 39723 and the first three degradation steps catalyzed by a PCP-4-monooxygenase (PcpB) and a reductive dehalogenase (PcpC) that functions twice are well established. A fourth step appears to involve ring-fission of the aromatic nucleus (PcpA). Molecular analyses revealed that the PCP degradation pathway in these four strains was rather conserved, leading to a phylogenetic analysis using 16S rDNA. The results revealed a much closer phylogenetic relationship between these organisms than traditional classification indicated, placing them into the more recently established genus Sphingomonas where they may even represent a single species. With 16S rDNA analysis, many bacterial isolates involved in degradation of xenobiotic compounds that were previously classified into diverse genera have been reclassified into the genus Sphingomonas.

Journal Article↗
PubMed1999

Ecology, physiology, and phylogeny of deep subsurface Sphingomonas sp.

Several new species of the genus Sphingomonas including S. aromaticivorans, S. stygia, and S. subterranea that have the capacity for degrading a broad range of aromatic compounds including toluene, naphthalene, xylenes, p-cresol, fluorene, biphenyl, and dibenzothiophene, were isolated from deeply-buried (>200 m) sediments of the US Atlantic coastal plain (ACP). In S. aromaticivorans F199, many of the genes involved in the catabolism of these aromatic compounds are encoded on a 184-kb conjugative plasmid; some of the genes involved in aromatic catabolism are plasmid-encoded in the other strains as well. Members of the genus Sphingomonas were common among aerobic heterotrophic bacteria cultured from ACP sediments and have been detected in deep subsurface environments elsewhere. The major source of organic carbon for heterotrophic metabolism in ACP deep aquifers is lignite that originated from plant material buried with the sediments. We speculate that the ability of the subsurface Sphingomonas strains to degrade a wide array of aromatic compounds represents an adaptation for utilization of sedimentary lignite. These and related subsurface Sphingomonas spp may play an important role in the transformation of sedimentary organic carbon in the aerobic and microaerobic regions of the deep aquifers of the ACP.

Journal Article↗
PubMed1998

Characterization and reclassification of an aromatic- and chloroaromatic-degrading Pseudomonas sp., strain HV3, as Sphingomonas sp. HV3.

Phylogenetic analyses of 16S rRNA gene sequences showed that the Gram-negative aromatic- and chloroaromatic-degrading Pseudomonas sp. strain HV3 carrying the mega-plasmid pSKY4 belongs to the genus Sphingomonas. The 16SrRNA sequence is most related to Sphingomonas chlorophenolica strains ATCC 33790(T) (98.5%) and SR3 (98.4%) and Sphingomonas sp. SS86 (98.4%). The G+C content was 64 mol%, and the DNA-DNA hybridization-based relative homology of strain HV3 to the S. chlorophenolica ATCC 33790(T) and S. chlorophenolica RA2 was 59.6% and 35.9%, respectively. The results showed that although strain HV3 is related to S. chlorophenolica it differs in certain characteristics. It is therefore proposed to reclassify Pseudomonas sp. strain HV3 as Sphingomonas sp. HV3.

Base Sequence↗
PubMed2002

Isolation and characterization of Sphingomonas sp. GTIN11 capable of carbazole metabolism in petroleum.

A bacterial culture was isolated from a manufactured gas plant (MGP) soil based on its ability to metabolize the nitrogen-containing heterocycle carbazole. The culture was identified as a Sphingomonas sp. and was given the designation GTIN11. A cloned 4.2kb DNA fragment was confirmed to contain genes responsible for carbazole degradation. DNA sequence analysis revealed that the fragment contained five open reading frames (ORFs) with the deduced amino acid sequence showing homology to; carbazole terminal dioxygenase (ORF1), 2,3-dihydroxybiphenyl dioxygenase subunits (ORF2 and ORF3), meta-cleavage compound hydrolases (ORF4), and ferrodoxin component of bacterial multicomponent dioxygenases (ORF5). The percent similarity was 61% of these proteins or less to known proteins. The specific activity of Sphingomonas sp. GTIN11 for the degradation of carbazole at 37 degrees C was determined to be 8.0 micromol carbazole degraded/min/g dry cell. This strain is unique in expressing the carbazole degradation trait constitutively. Resting cells of Sphingomonas sp. GTIN11 removed 95% of carbazole and 50% of C1-carbazoles from petroleum in a 16-h treatment time.

Biodegradation, Environmental↗
PubMed2000

Microbial degradation of poly(aspartic acid) by two isolated strains of Pedobacter sp. and Sphingomonas sp.

Microbial degradation of thermally synthesized poly(aspartic acid) (PAA) was investigated. A PAA-P1 sample (Mn, 7500; Mw, 20,000; number of branched units/100 monomer units, 3.1) was completely degraded in natural river water within 15 days at 25 degrees C. A new PAA-degrading bacterium (strain KP-2: JCM10638) was isolated together with Sphingomonas sp. KT-1 (JCM10459) from river water, and identified as a member of Pedobacter. A Pedobacter isolate was capable of degrading high-molecular-weight PAA polymers of 5000 to 150,000, and a small amount of low-molecular-weight products of 250 to 5000 was accumulated as residues during the growth of the isolate on PAA. In contrast, the other isolate Sphingomonas sp. KT-1 degraded only low-molecular-weight PAA below 5000. A mixed culturing of Pedobacter sp. KP-2 with Sphingomonas sp. KT-1 resulted in a complete degradation of PAA-P1 sample, but a small amount of low molecular weight components was accumulated during the degradation of highly branched PAA-P2 and PAA-P3 samples.

Bacteria↗
PubMed2001

Preparation of (R)- and (S)-N-protected 3-hydroxypyrrolidines by hydroxylation with Sphingomonas sp. HXN-200, a highly active, regio- and stereoselective, and easy to handle biocatalyst.

Hydroxylation of N-benzylpyrrolidine 8 with resting cells of Sphingomonas sp. HXN-200 gave N-benzyl-3-hydroxypyrrolidine 15 in 53% ee (S) with an activity of 5.8 U/g CDW. By changing the "docking/protecting group" in pyrrolidines, hydroxylation activity and enantioselectivity were further improved and the enantiocomplementary formation of 3-hydroxypyrrolidines was achieved: hydroxylation of N-benzoyl-, N-benzyloxycarbonyl-, N-phenoxycarbonyl-, and N-tert-butoxycarbonyl-pyrrolidines 9-12 gave the corresponding 3-hydroxypyrrolidines 16-19 in ee of 52% (R), 75% (R), 39% (S), and 23% (R), respectively, with an activity of 2.2, 16, 14, and 24 U/g CDW, respectively. Simple crystallizations increased the ee of 16-18 to 95% (R), 98% (R), and 96% (S), respectively. Hydroxylation of pyrrolidines 8-12 with soluble cell-free extracts of Sphingomonas sp. HXN-200 and equimolar NADH gave 3-hydroxypyrrolidines 15-19 in nearly the same ee as the products generated by whole cell transformation, suggesting that this strain possesses a novel soluble alkane monooxygenase. Cells of Sphingomonas sp. HXN-200 were produced in large amounts and could be stored at -80 degrees C for 2 years without significant loss of activity. The frozen cells can be thawed and resuspended for biohydroxylation, providing a highly active and easy to handle biocatalyst for the regio- and stereoselective hydroxylation of nonactivated carbon atoms. These cells were used to prepare 1.0-3.2 g (66.4-93.5% yield) of 3-hydroxypyrrolidines 16-19 by hydroxylation of pyrrolidines 9-12 on 0.9-2 L scale. Preparative hydroxylation was also achieved with growing cells as biocatalysts; hydroxylation of pyrrolidine 11 on 1 L scale gave 1.970 g (79.7% yield) of 3-hydroxypyrrolidine 18.

Catalysis↗
PubMed2001

Sphingomonas alaskensis sp. nov., a dominant bacterium from a marine oligotrophic environment.

Seven Gram-negative strains, isolated in 1990 from a 10(6)-fold dilution series of seawater from Resurrection Bay, a deep fjord of the Gulf of Alaska, were identified in a polyphasic taxonomic study. Analysis of 16S rDNA sequences and DNA-homology studies confirmed the phylogenetic position of all strains in the genus Sphingomonas and further indicated that all of the strains constitute a single homogeneous genomic species, distinct from all validly described Sphingomonas species. The ability to differentiate the species, both phenotypically and chemotaxonomically, from its nearest neighbours justifies the proposal of a new species name, Sphingomonas alaskensis sp. nov., for this taxon. Strain LMG 18877T (= RB2256T = DSM 13593T) was selected as the type strain.

Bacterial Typing Techniques↗
PubMed2005

Architecture of a nascent Sphingomonas sp. biofilm under varied hydrodynamic conditions.

The architecture of a Sphingomonas biofilm was studied during early phases of its formation, using strain L138, a gfp-tagged derivative of Sphingomonas sp. strain LB126, as a model organism and flow cells and confocal laser scanning microscopy as experimental tools. Spatial and temporal distribution of cells and exopolymer secretions (EPS) within the biofilm, development of microcolonies under flow conditions representing varied Reynolds numbers, and changes in diffusion length with reference to EPS production were studied by sequential sacrificing of biofilms grown in multichannel flow cells and by time-lapse confocal imaging. The area of biofilm in terms of microscopic images required to ensure representative sampling varied by an order of magnitude when area of cell coverage (2 x 10(5) microm(2)) or microcolony size (1 x 10(6) microm(2)) was the biofilm parameter under investigation. Hence, it is necessary to establish the inherent variability of any biofilm metric one is attempting to quantify. Sphingomonas sp. strain L138 biofilm architecture consisted of microcolonies and extensive water channels. Biomass and EPS distribution were maximal at 8 to 9 mum above the substratum, with a high void fraction near the substratum. Time-lapse confocal imaging and digital image analysis showed that growth of the microcolonies was not uniform: adjacently located colonies registered significant growth or no growth at all. Microcolonies in the biofilm had the ability to move across the attachment surface as a unit, irrespective of fluid flow direction, indicating that movement of microcolonies is an inherent property of the biofilm. Width of water channels decreased as EPS production increased, resulting in increased diffusion distances in the biofilm. Changing hydrodynamic conditions (Reynolds numbers of 0.07, 52, and 87) had no discernible influence on the characteristics of microcolonies (size, shape, or orientation with respect to flow) during the first 24 h of biofilm development. Inherent factors appear to have overriding influence, vis-a-vis environmental factors, on early stages of microcolony development under these laminar flow conditions.

Biofilms↗
PubMed2000

Monitoring by laser-flow-cytometry of the polycyclic aromatic hydrocarbon-degrading Sphingomonas sp. strain 107 during biotreatment of a contaminated soil.

A flow cytometric method (FCM) was used to detect and accurately enumerate a polycyclic aromatic hydrocarbon-degrading bacterial strain, Sphingomonas sp. 107, inoculated into a soil sample artificially contaminated with pyrene. To compare the FCM method with colony forming unit (CFU) assays, a rifampicin-resistant Sphingomonas sp. 107 was obtained which could be distinguished from the indigenous microflora, since there was no organism resistant to rifampicin in the soil that could transform indole to indigo (naphthalene dioxygenase activity). By combining light-scattering profiles (i.e., morphological properties), ethidium bromide influx (i.e., cell wall permeability), and fluorescence in situ hybridization against the 16S rRNA (i.e., detection specificity), we could enumerate the bacterial population of interest from the indigenous microflora and soil debris during the biotreatment. The FCM technique revealed that the number of inoculated Sphingomonas cells decreased gradually for 15 days of incubation before reaching a steady level of 7 to 12 x 10(5) cells.g-1 of soil. Similar values were obtained with the CFU assay. During this period, pyrene concentration decreased from 632 to 26 mg.kg-1 of dry soil. The FCM detection was improved by adding blocking reagent to the hybridization buffer to minimize the non-specific attachment of the fluorescent probe to soil particles. Combined with the improvements in probe technology, FCM detection was shown to be a good alternative to the conventional culture methods for the analysis of bacterial populations in environmental samples. This technique could be potentially useful for the detection of microorganisms that grow poorly in culture.

Biodegradation, Environmental↗
PubMed1999

Chemical structure and function of glycosphingolipids of Sphingomonas spp and their distribution among members of the alpha-4 subclass of Proteobacteria.

Sphingomonas spp are phylogenetically placed in the alpha-4 subclass of Proteobacteria. They have glycosphingolipids (GSL) in their membranes instead of lipopolysaccharide (LPS) as in other Gram-negative bacteria. S. paucimobilis, the type species of the genus, has GSL-1, which contains only glucuronic acid (GlcA) as a sugar moiety, and GSL-4A, which contains a tetrasaccharide including GlcA. GSL-1 and GSL-4A form the outer membrane of S. paucimobilis with outer membrane proteins and phospholipids. In the outer membrane, GSLs are assumed to locate and function as does the LPS of other Gram-negative bacteria. Sphingomonas spp closely related to the type species contain both GSL-1 and the oligosaccharide-type GSL such as GSL-4A, but other Sphingomonas spp and other genera in the alpha-4 subclass of Proteobacteria contain only GSL-1. Structural variations of fatty acids and dihydrosphingosines in the GSL-1 are presented.

Journal Article↗
PubMed1999

Colonization of contaminated soil by an introduced bacterium: effects of initial pentachlorophenol levels on the survival of Sphingomonas chlorophenolica strain RA2.

The survival of a Sphingomonas species that was introduced into pentachlorophenol (PCP)-contaminated soil was monitored with two complementary methods, a respiration-based assay and a most probable number (MPN) technique. Sphingomonas chlorophenolicastrain RA2 is a PCP-mineralizing bacterium that was introduced into soil contaminated with a range of PCP concentrations (0-300 &mgr;g PCP g(-1) soil). The population of introduced microorganisms was followed for 170 days using a substrate-induced growth-response method and a MPN assay that specifically targets PCP-mineralizing bacteria. Varying the initial PCP concentration resulted in the emergence of three distinct patterns of survival. In soil contaminated with 300 &mgr;g PCP g(-1) the population of S. chlorophenolica strain RA2 immediately declined following introduction, increased by 200-fold and leveled off by the end of the 170-day incubation. In contrast, populations of S. chlorophenolica strain RA2 declined to levels below detection limits in uncontaminated soil by the end of the experiment. Intermediate PCP concentrations (10-100 &mgr;g PCP g(-1) soil) resulted in the establishment of S. chlorophenolica strain RA2 that slowly declined in numbers. These results indicate that Sphingomonas chlorophenolica strain RA2 is an effective colonizer of PCP-contaminated soil but will not persist in the absence of PCP.

Journal Article↗
PubMed1999

Lessons learned from Sphingomonas species that degrade abietane triterpenoids.

Abietane terpenoid-degrading organisms include Sphingomonas spp which inhabit natural environments and biological treatment systems. An isolate from the high Arctic indicates that these organisms occur far from trees which synthesize abietanes and suggests that some of these organisms can occupy a niche in hydrocarbon-degrading soil communities. Abietane-degrading Sphingomonas spp provide additional evidence that the phylogeny of this genus is independent of the catabolic capabilities of its members. Studies of Sphingomonas sp DhA-33 demonstrate that biological treatment systems for pulp mill effluents have the potential to mineralize abietane resin acids. On the other hand, these studies indicate that some chlorinated dehydroabietic acids are quite recalcitrant. Strain DhA-33 grows relatively well on some chlorinated dehydroabietic acids but transforms others to stable metabolites. Using strain DhA-33, a novel method was developed to measure the metabolic activity of an individual population within a complex microbial community. Oligonucleotide hybridization probes were used to assay the 16S rRNA:rDNA ratio of DhA-33 as it grew in an activated sludge community. However, this method proved not to be sufficiently sensitive to measure naturally occurring resin acid-degrading populations. We propose that the same approach can be modified to use more sensitive assays.

Journal Article↗
PubMed1999

Interaction of Sphingomonas and Pseudomonas strains in the degradation of chlorinated dibenzofurans.

We have studied the concerted degradation of two monochlorodibenzofurans by a bacterial consortium, consisting of the chlorodibenzofurans-cometabolizing and chlorosalicylates-excreting strain Sphingomonas sp RW16, and Pseudomonas sp RW10, which mineralized the released chlorosalicylates. Neither of the organisms was able to grow with chlorodibenzofurans alone. Degradation of 2-chloro- and 3-chlorodibenzofuran proceeded to the end products 5-chloro- and 4-chlorosalicylate, respectively, when the initial dioxygenase of Sphingomonas sp RW 16 attacked the unchlorinated aromatic ring of the heterocyclic dibenzofuran molecule. 2-Hydroxypenta-2,4-dienoate, formed upon meta-cleavage of the intermediary chlorotrihydroxybiphenyls, served as a growth substrate for the sphingomonad. Presumably, most of the chlorosalicylates were excreted and degraded further by Pseudomonas sp RW10. Mineralization of both chlorosalicylates proceeded through a converging pathway, via 4-chlorocatechol, and protoanemonin. Chlorosalicylates were mineralized by the pseudomonad only when their concentration in the culture medium was below 1.5 mM. In the case of initial dioxygenation taking place on the chlorinated aromatic ring, salicylate and chlorinated hydroxypentadienoates should be formed. The metabolic fate of putative chlorohydroxypentadienoates is not clear; ie, they may be channeled into unproductive catabolism and, thus, represent the critical point in the breakdown of the carbon of these two chlorodibenzofurans by Sphingomonas sp RW16.

Journal Article↗
PubMed1999

Degradation of azo dyes containing aminonaphthol by Sphingomonas sp strain 1CX.

Sphingomonas sp strain 1CX was isolated from a wastewater treatment plant and is capable of aerobically degrading a suite of azo dyes, using them as a sole source of carbon and nitrogen. All azo dyes known to be decolorized by strain 1CX (Orange II, Acid Orange 8, Acid Orange 10, Acid Red 4, and Acid Red 88) have in their structure either 1-amino-2-naphthol or 2-amino-1-naphthol. In addition, an analysis of the structures of the dyes degraded suggests that there are certain positions and types of substituents on the azo dye which determine if degradation will occur. Growth and dye decolorization occurs only aerobically and does not occur under fermentative or denitrification conditions. The mechanism by which 1CX decolorizes azo dyes appears to be through reductive cleavage of the azo bond. In the case of Orange II, the initial degradation products were sulfanilic acid and 1-amino-2-naphthol. Sulfanilic acid, however, was not used by 1CX as a growth substrate. The addition of glucose or inorganic nitrogen inhibited growth and decoloration of azo dyes by 1CX. Attempts to grow the organism on chemically defined media containing several different amino acids and sugars as sources of nitrogen and carbon were not successful. Phylogenetic analysis of Sphingomonas sp strain 1CX shows it to be related to, but distinct from, other azo dye-decolorizing Sphingomonas spp strains isolated previously from the same wastewater treatment facility.

Journal Article↗
PubMed1999

Chlorophenol and nitrophenol metabolism by Sphingomonas sp UG30.

Sphingomonas sp UG30 is a pentachlorophenol (PCP)-degrading bacterial strain capable of degrading several nitrophenolic compounds, including p-nitrophenol (PNP), 2,4-dinitrophenol (2,4-DNP), p-nitrocatechol and 4,6-dinitro-o-cresol (DNOC). The ability to degrade both chlorophenolic and nitrophenolic compounds is probably not restricted to UG30, but may also be possessed by other pentachlorophenol-degrading Sphingomonas spp. The interesting question arises as to whether there is any point of convergence between the initial pathways of PCP and nitrophenol degradation in these microorganisms. There is some experimental evidence that PCP-4-monooxygenase is involved in metabolism of both p-nitrophenol and 2,4-dinitrophenol. Further studies are needed to confirm this and to examine the role(s) of other PCP-degrading enzymes in nitrophenol metabolism by this microorganism. In this paper, we review some of the taxonomic, biochemical, physiological and ecological properties of Sphingomonas sp UG30 with respect to biodegradation of PCP and nitrophenolic compounds.

Journal Article↗
PubMed1994

Phylogenetic evidence for Sphingomonas and Rhizomonas as nonphotosynthetic members of the alpha-4 subclass of the Proteobacteria.

To clarify the taxonomic relationships of the genera Rhizomonas and Sphingomonas, the 16S rRNA sequence of Rhizomonas suberifaciens IFO 15211T (T = type strain) was determined. A phylogenetic analysis of aligned 16S rRNA gene sequences revealed that eight species of the genus Sphingomonas and R. suberifaciens are closely related to Erythrobacter longus and Porphyrobacter neustonensis and, therefore, belong in the alpha-4 subclass of the Proteobacteria. Within this subclass, Sphingomonas species and R. suberifaciens are phylogenetically interrelated and comprise several subgroups. Our findings show that the genus and species definitions of these organisms are in need of revision.

Bacteriochlorophylls↗
PubMed2003

Sphingopyxis chilensis sp. nov., a chlorophenol-degrading bacterium that accumulates polyhydroxyalkanoate, and transfer of Sphingomonas alaskensis to Sphingopyxis alaskensis comb. nov.

The taxonomic position of a chlorophenol-degrading bacterium, strain S37T, was investigated. The 16S rDNA sequence indicated that this strain belongs to the genus Sphingopyxis, exhibiting high sequence similarity to the 16S rDNA sequences of Sphingomonas alaskensis LMG 18877T (98.8%), Sphingopyxis macrogoltabida LMG 17324T (98.2%), Sphingopyxis terrae IFO 15098T (95%) and Sphingomonas adhaesiva GIFU 11458T (92%). These strains (except Sphingopyxis terrae IFO 15098T, which was not investigated) and the novel isolate accumulated polyhydroxyalkanoates consisting of 3-hydroxybutyric acid and 3-hydroxyvaleric acid from glucose as carbon source. The G + C content of the DNA of strain S37T was 65.5 mol%. The major cellular fatty acids of this strain were octadecenoic acid (18 : 1omega7c), heptadecenoic acid (17 : 1omega6c) and hexadecanoic acid (16 : 0). The results of DNA-DNA hybridization experiments and its physiological characteristics clearly distinguished the novel isolate from all known Sphingopyxis species and indicated that the strain represents a novel Sphingopyxis species. Therefore, the species Sphingopyxis chilensis sp. nov. is proposed, with strain S37T (=LMG 20986T =DSM 14889T) as the type strain. The transfer of Sphingomonas alaskensis to the genus Sphingopyxis as Sphingopyxis alaskensis comb. nov. is also proposed.

Alphaproteobacteria↗
PubMed1997

Molecular characterization of Fdx1, a putidaredoxin-type [2Fe-2S] ferredoxin able to transfer electrons to the dioxin dioxygenase of Sphingomonas sp. RW1.

Bacterium Sphingomonas sp. strain RW1 is, under aerobic conditions, able to degrade dibenzofuran and dibenzo-p-dioxin. The first step of the pathway is performed by a ring-dihydroxylating enzyme. Bunz and Cook have reported the purification and characterization of this dioxin dioxygenase and a ferredoxin able to transfer electrons to the dioxygenase [Bunz, P. V. & Cook, A. M. (1993) J. Bacteriol. 175, 6467-6475]. The gene encoding this [2Fe-2S] ferredoxin was identified by screening a genomic library constructed in pLAFR3 with a probe generated by a nested-PCR amplification. Primers for the amplification were designed based on the N-terminus sequence of the purified ferredoxin and on sequence comparisons with related proteins. Several cosmids were obtained and the ferredoxin gene, fdx1, was subcloned from one of them. The nucleotide sequence of a 4.6-kb DNA fragment encompassing the ferredoxin gene was determined. While in the case of all known multi-component dioxygenases, genes encoding the alpha and beta subunits are found to be contiguous with the gene of the specific electron carrier, the fdx1 gene in Sphingomonas sp. RW1 does not appear to be directly linked with the dioxin dioxygenase genes. Rather, it is clustered with genes apparently encoding two atypical decarboxylases/isomerases and a glutathione S-transferase. The ferredoxin gene was hyperexpressed and the recombinant ferredoxin was purified. Spectroscopic characterization of Fdx1 demonstrated the presence of a putidaredoxin-type [2Fe-2S] cluster in this protein. Its redox potential was determined to be -245 (+/- 5) mV versus the normal hydrogen electrode at 25 degrees C, pH 8.0. Therefore, the protein is closely related to [2Fe-2S] ferredoxins known to be electron donors to monooxygenases involved in hydroxylation of aromatic compounds. Thus, this report provides clear evidence that a putidaredoxin-type [2Fe-2S] ferredoxin, namely Fdx1, is able to transfer electrons to the dioxin dioxygenase of Sphingomonas sp. RW1.

Amino Acid Sequence↗