-
Remarkable ability of Pandoraea pnomenusa B356 biphenyl dioxygenase to metabolize simple flavonoids.Applied and Environmental Microbiology May 2012Many investigations have provided evidence that plant secondary metabolites, especially flavonoids, may serve as signal molecules to trigger the abilities of bacteria to...
Many investigations have provided evidence that plant secondary metabolites, especially flavonoids, may serve as signal molecules to trigger the abilities of bacteria to degrade chlorobiphenyls in soil. However, the bases for this interaction are largely unknown. In this work, we found that BphAE(B356), the biphenyl/chlorobiphenyl dioxygenase from Pandoraea pnomenusa B356, is significantly better fitted to metabolize flavone, isoflavone, and flavanone than BphAE(LB400) from Burkholderia xenovorans LB400. Unlike those of BphAE(LB400), the kinetic parameters of BphAE(B356) toward these flavonoids were in the same range as for biphenyl. In addition, remarkably, the biphenyl catabolic pathway of strain B356 was strongly induced by isoflavone, whereas none of the three flavonoids induced the catabolic pathway of strain LB400. Docking experiments that replaced biphenyl in the biphenyl-bound form of the enzymes with flavone, isoflavone, or flavanone showed that the superior ability of BphAE(B356) over BphAE(LB400) is principally attributable to the replacement of Phe336 of BphAE(LB400) by Ile334 and of Thr335 of BphAE(LB400) by Gly333 of BphAE(B356). However, biochemical and structural comparison of BphAE(B356) with BphAE(p4), a mutant of BphAE(LB400) which was obtained in a previous work by the double substitution Phe336Met Thr335Ala of BphAE(LB400), provided evidence that other residues or structural features of BphAE(B356) whose precise identification the docking experiment did not allow are also responsible for the superior catalytic abilities of BphAE(B356). Together, these data provide supporting evidence that the biphenyl catabolic pathways have evolved divergently among proteobacteria, where some of them may serve ecological functions related to the metabolism of plant secondary metabolites in soil.
Topics: Amino Acid Substitution; Biphenyl Compounds; Burkholderiaceae; Dioxygenases; Flavonoids; Gene Expression Regulation, Bacterial; Kinetics; Metabolic Networks and Pathways; Protein Conformation
PubMed: 22427498
DOI: 10.1128/AEM.00225-12 -
Journal of Bacteriology Aug 2007Biphenyl dioxygenase (BPDO) catalyzes the aerobic transformation of biphenyl and various polychlorinated biphenyls (PCBs). In three different assays, BPDO(B356) from... (Comparative Study)
Comparative Study
Biphenyl dioxygenase (BPDO) catalyzes the aerobic transformation of biphenyl and various polychlorinated biphenyls (PCBs). In three different assays, BPDO(B356) from Pandoraea pnomenusa B-356 was a more potent PCB-degrading enzyme than BPDO(LB400) from Burkholderia xenovorans LB400 (75% amino acid sequence identity), transforming nine congeners in the following order of preference: 2,3',4-trichloro approximately 2,3,4'-trichloro > 3,3'-dichloro > 2,4,4'-trichloro > 4,4'-dichloro approximately 2,2'-dichloro > 2,6-dichloro > 2,2',3,3'-tetrachloro approximately 2,2',5,5'-tetrachloro. Except for 2,2',5,5'-tetrachlorobiphenyl, BPDO(B356) transformed each congener at a higher rate than BPDO(LB400). The assays used either whole cells or purified enzymes and either individual congeners or mixtures of congeners. Product analyses established previously unrecognized BPDO(B356) activities, including the 3,4-dihydroxylation of 2,6-dichlorobiphenyl. BPDO(LB400) had a greater apparent specificity for biphenyl than BPDO(B356) (k(cat)/K(m) = 2.4 x 10(6) +/- 0.7 x 10(6) M(-1) s(-1) versus k(cat)/K(m) = 0.21 x 10(6) +/- 0.04 x 10(6) M(-1) s(-1)). However, the latter transformed biphenyl at a higher maximal rate (k(cat) = 4.1 +/- 0.2 s(-1) versus k(cat) = 0.4 +/- 0.1 s(-1)). A variant of BPDO(LB400) containing four active site residues of BPDO(B356) transformed para-substituted congeners better than BPDO(LB400). Interestingly, a substitution remote from the active site, A267S, increased the enzyme's preference for meta-substituted congeners. Moreover, this substitution had a greater effect on the kinetics of biphenyl utilization than substitutions in the substrate-binding pocket. In all variants, the degree of coupling between congener depletion and O(2) consumption was approximately proportional to congener depletion. At 2.4-A resolution, the crystal structure of the BPDO(B356)-2,6-dichlorobiphenyl complex, the first crystal structure of a BPDO-PCB complex, provided additional insight into the reactivity of this isozyme with this congener, as well as into the differences in congener preferences of the BPDOs.
Topics: Amino Acid Substitution; Biotransformation; Burkholderiaceae; Crystallography, X-Ray; Gas Chromatography-Mass Spectrometry; Iron-Sulfur Proteins; Kinetics; Magnetic Resonance Spectroscopy; Models, Molecular; Oxygenases; Polychlorinated Biphenyls; Protein Structure, Tertiary; Substrate Specificity
PubMed: 17526697
DOI: 10.1128/JB.01476-06 -
Genome Announcements Feb 2015Pandoraea is an emerging respiratory pathogen capable of causing chronic lung infections in people with cystic fibrosis (CF), but the clinical significance of this...
Pandoraea is an emerging respiratory pathogen capable of causing chronic lung infections in people with cystic fibrosis (CF), but the clinical significance of this infection is ambiguous. We have sequenced and annotated the genomes of two multidrug-resistant Pandoraea pnomenusa isolates recovered 11 months apart from the same CF patient.
PubMed: 25657265
DOI: 10.1128/genomeA.01389-14 -
Frontiers in Microbiology 2016
PubMed: 26903988
DOI: 10.3389/fmicb.2016.00109 -
International Microbiology : the... Feb 2024Polymyxin B is considered a last-line therapeutic option against multidrug-resistant gram-negative bacteria, especially in COVID-19 coinfections or other serious...
BACKGROUND
Polymyxin B is considered a last-line therapeutic option against multidrug-resistant gram-negative bacteria, especially in COVID-19 coinfections or other serious infections. However, the risk of antimicrobial resistance and its spread to the environment should be brought to the forefront.
METHODS
Pandoraea pnomenusa M202 was isolated under selection with 8 mg/L polymyxin B from hospital sewage and then was sequenced by the PacBio RS II and Illumina HiSeq 4000 platforms. Mating experiments were performed to evaluate the transfer of the major facilitator superfamily (MFS) transporter in genomic islands (GIs) to Escherichia coli 25DN. The recombinant E. coli strain Mrc-3 harboring MFS transporter encoding gene FKQ53_RS21695 was also constructed. The influence of efflux pump inhibitors (EPIs) on MICs was determined. The mechanism of polymyxin B excretion mediated by FKQ53_RS21695 was investigated by Discovery Studio 2.0 based on homology modeling.
RESULTS
The MIC of polymyxin B for the multidrug-resistant bacterial strain P. pnomenusa M202, isolated from hospital sewage, was 96 mg/L. GI-M202a, harboring an MFS transporter-encoding gene and conjugative transfer protein-encoding genes of the type IV secretion system, was identified in P. pnomenusa M202. The mating experiment between M202 and E. coli 25DN reflected the transferability of polymyxin B resistance via GI-M202a. EPI and heterogeneous expression assays also suggested that the MFS transporter gene FKQ53_RS21695 in GI-M202a was responsible for polymyxin B resistance. Molecular docking revealed that the polymyxin B fatty acyl group inserts into the hydrophobic region of the transmembrane core with Pi-alkyl and unfavorable bump interactions, and then polymyxin B rotates around Tyr43 to externally display the peptide group during the efflux process, accompanied by an inward-to-outward conformational change in the MFS transporter. Additionally, verapamil and CCCP exhibited significant inhibition via competition for binding sites.
CONCLUSIONS
These findings demonstrated that GI-M202a along with the MFS transporter FKQ53_RS21695 in P. pnomenusa M202 could mediate the transmission of polymyxin B resistance.
Topics: Polymyxin B; Escherichia coli; Genomic Islands; Molecular Docking Simulation; Sewage; Membrane Transport Proteins; Anti-Bacterial Agents; Microbial Sensitivity Tests; Burkholderiaceae
PubMed: 37316617
DOI: 10.1007/s10123-023-00384-8 -
Journal of Biotechnology Nov 2015Pandoraea pnomenusa RB-38 is a bacterium isolated from a former sanitary landfill site. Here, we present the complete genome of P. pnomenusa RB38 in which an oxalate...
Pandoraea pnomenusa RB-38 is a bacterium isolated from a former sanitary landfill site. Here, we present the complete genome of P. pnomenusa RB38 in which an oxalate utilization pathway was identified. The genome analysis suggested the potential of this strain as an effective biocontrol agent against oxalate-producing phytopathogens.
Topics: Burkholderiaceae; DNA, Bacterial; Environmental Microbiology; Genome, Bacterial; Solid Waste; Waste Disposal Facilities
PubMed: 26393955
DOI: 10.1016/j.jbiotec.2015.09.018 -
The Journal of Biological Chemistry Oct 2011Biphenyl dehydrogenase, a member of short-chain dehydrogenase/reductase enzymes, catalyzes the second step of the biphenyl/polychlorinated biphenyls catabolic pathway in...
Biphenyl dehydrogenase, a member of short-chain dehydrogenase/reductase enzymes, catalyzes the second step of the biphenyl/polychlorinated biphenyls catabolic pathway in bacteria. To understand the molecular basis for the broad substrate specificity of Pandoraea pnomenusa strain B-356 biphenyl dehydrogenase (BphB(B-356)), the crystal structures of the apo-enzyme, the binary complex with NAD(+), and the ternary complexes with NAD(+)-2,3-dihydroxybiphenyl and NAD(+)-4,4'-dihydroxybiphenyl were determined at 2.2-, 2.5-, 2.4-, and 2.1-Å resolutions, respectively. A crystal structure representing an intermediate state of the enzyme was also obtained in which the substrate binding loop was ordered as compared with the apo and binary forms but it was displaced significantly with respect to the ternary structures. These five structures reveal that the substrate binding loop is highly mobile and that its conformation changes during ligand binding, starting from a disorganized loop in the apo state to a well organized loop structure in the ligand-bound form. Conformational changes are induced during ligand binding; forming a well defined cavity to accommodate a wide variety of substrates. This explains the biochemical data that shows BphB(B-356) converts the dihydrodiol metabolites of 3,3'-dichlorobiphenyl, 2,4,4'-trichlorobiphenyl, and 2,6-dichlorobiphenyl to their respective dihydroxy metabolites. For the first time, a combination of structural, biochemical, and molecular docking studies of BphB(B-356) elucidate the unique ability of the enzyme to transform the cis-dihydrodiols of double meta-, para-, and ortho-substituted chlorobiphenyls.
Topics: Bacterial Proteins; Burkholderiaceae; Chlorophenols; Crystallography, X-Ray; Ligands; Oxidoreductases; Protein Structure, Quaternary; Protein Structure, Secondary; Protein Structure, Tertiary; Structure-Activity Relationship; Substrate Specificity
PubMed: 21880718
DOI: 10.1074/jbc.M111.291013 -
Journal of Medical Microbiology Jan 2008Pandoraea species are emerging opportunistic pathogens capable of causing chronic lung infections in cystic fibrosis patients. This study examined the interactions of 17...
Pandoraea species are emerging opportunistic pathogens capable of causing chronic lung infections in cystic fibrosis patients. This study examined the interactions of 17 Pandoraea isolates from the five identified species (Pandoraea apista, Pandoraea norimbergensis, Pandoraea pulmonicula, Pandoraea sputorum and Pandoraea pnomenusa) plus two Pandoraea genomospecies isolates with lung epithelial cells and their ability to form biofilms in vitro. Only three isolates showed an ability to invade A549 lung epithelial cells, and only one isolate was able to form biofilms. In contrast, all isolates triggered a pronounced pro-inflammatory response, with elevation of both interleukin (IL)-6 (two- to 19-fold) and IL-8 (10- to 50-fold) above that observed for a control strain of Escherichia coli. This property is likely to be a major factor in the pathogenesis of the genus.
Topics: Betaproteobacteria; Biofilms; Cell Line; Epithelial Cells; Lung; Virulence
PubMed: 18065662
DOI: 10.1099/jmm.0.47544-0 -
International Journal of Systematic and... Sep 2016A Gram-staining-negative, facultatively aerobic, white-colony-forming bacterium, designated strain SE-S21T, was isolated from forest soil of Jeju Island in Korea. Cells...
A Gram-staining-negative, facultatively aerobic, white-colony-forming bacterium, designated strain SE-S21T, was isolated from forest soil of Jeju Island in Korea. Cells were motile rods with a single polar flagellum, showing catalase- and oxidase-positive reactions. Growth was observed at 10-40 °C (optimum, 30 °C), pH 4.0-10.0 (optimum, pH 7.0-7.5) and with 0-4.0 % (w/v) NaCl (optimum, 0-2 %). Only ubiquinone-8 was detected as the isoprenoid quinone, and C16 : 0, C17 : 0 cyclo, C19 : 1ω8c cyclo and summed feature 2 (comprising C12 : 0 aldehyde and/or unknown) were found to be the major fatty acids. Phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, an unknown aminophospholipid, an unknown aminolipid and an unknown lipid were detected as the major polar lipids. Putrescine and 2-hydroxyputrescine were the predominant polyamines. The DNA G+C content was 61.0 mol%. Phylogenetic analyses based on 16S rRNA and DNA gyrase B gene sequences revealed that strain SE-S21T formed a phyletic lineage within the genus Pandoraea. Strain SE-S21T was most closely related to Pandoraea faecigallinarum KOxT and Pandoraea pnomenusa CCUG 38742T with 98.8 % and 98.7 % 16S rRNA gene sequence similarities, respectively. However, the DNA-DNA relatedness values between strain SE-S21T and the type strains of P. faecigallinarum and P. pnomenusa were 26.6±5.7 % and 20.5±3.7 %, respectively. On the basis of phenotypic, chemotaxonomic and molecular features, strain SE-S21T clearly represents a novel species of the genus Pandoraea, for which the name Pandoraea terrae sp. nov. is proposed. The type strain is SE-S21T (=KACC 18127T=JCM 30137T). An emended description of the genus Pandoraea is also proposed.
Topics: Bacterial Typing Techniques; Base Composition; Burkholderiaceae; DNA, Bacterial; Fatty Acids; Forests; Islands; Nucleic Acid Hybridization; Phospholipids; Phylogeny; Putrescine; RNA, Ribosomal, 16S; Republic of Korea; Sequence Analysis, DNA; Soil Microbiology; Ubiquinone
PubMed: 27267599
DOI: 10.1099/ijsem.0.001229 -
International Journal of Systematic and... Jan 2010A facultatively chemolithoautotrophic, thiosulfate-oxidizing, Gram-negative, aerobic, motile, rod-shaped bacterial strain, designated ATSB16(T), was isolated from...
A facultatively chemolithoautotrophic, thiosulfate-oxidizing, Gram-negative, aerobic, motile, rod-shaped bacterial strain, designated ATSB16(T), was isolated from rhizosphere soils of sesame (Sesamum indicum L.). 16S rRNA gene sequence analysis demonstrated that this strain was closely related to Pandoraea pnomenusa LMG 18087(T) (96.7 % similarity), P. pulmonicola LMG 18016(T) (96.5 %), P. apista LMG 16407(T) (96.2 %), P. norimbergensis LMG 18379(T) (96.1 %) and P. sputorum LMG 18819(T) (96.0 %). Strain ATSB16(T) shared 96.0-96.4 % sequence similarity with four unnamed genomospecies of Pandoraea. The major cellular fatty acids of the strain ATSB16(T) were C(17 : 0) cyclo (33.0 %) and C(16 : 0) (30.6 %). Q-8 was the predominant respiratory quinone. The major polar lipids were phosphatidylmethylethanolamine, diphosphatidylglycerol, phosphatidylethanolamine and two unidentified aminophospholipids. Hydroxyputrescine and putrescine were the predominant polyamines. The genomic DNA G+C content of the strain was 64.0 mol%. On the basis of the results obtained from this study, strain ATSB16(T) represents a novel species of the genus Pandoraea, for which the name Pandoraea thiooxydans sp. nov. is proposed. The type strain is ATSB16(T) (=KACC 12757(T) =LMG 24779(T)).
Topics: Burkholderiaceae; Chemoautotrophic Growth; DNA, Bacterial; DNA, Ribosomal; Fatty Acids; Molecular Sequence Data; Oxidation-Reduction; Phylogeny; RNA, Ribosomal, 16S; Sesamum; Soil Microbiology; Thiosulfates
PubMed: 19643869
DOI: 10.1099/ijs.0.012823-0