Mechanism of Extradiol Catechol Dioxygenases: Evidence for a Lactone Intermediate in the 2,3-Dihydroxyphenylpropionate 1,2-Dioxygenase Reaction
74
Citation
0
Reference
10
Related Paper
Citation Trend
Abstract:
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMechanism of Extradiol Catechol Dioxygenases: Evidence for a Lactone Intermediate in the 2,3-Dihydroxyphenylpropionate 1,2-Dioxygenase ReactionJonathan Sanvoisin, G. John Langley, and Timothy D. H. BuggCite this: J. Am. Chem. Soc. 1995, 117, 29, 7836–7837Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://pubs.acs.org/doi/10.1021/ja00134a041https://doi.org/10.1021/ja00134a041research-articleACS PublicationsRequest reuse permissionsArticle Views457Altmetric-Citations62LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (2)»Supporting Information Supporting Information Get e-AlertsKeywords:
Catechol
Dioxygenase
Reaction intermediate
The main aim of this study was to purify Catechol 1, 2 dioxygenase from phenol utilizing Rhodococcus sp. NCIM 2891 which is basically an organism used wide for desulfurization purposes like desulfurization of diesel. The organism was cultivated in minimal medium supplemented with 500mg/L phenol, as a sole carbon source. The temperature of incubation was 30℃ at pH 7.0±0.2. The growth and phenol degradation studies show that organism was able to degrade the phenol completely within 120h. The stationary phase of growth of the organism, however, started after 72h. This implies that the degradation activities starts from late log phase and carries on till late stationary phase of growth. The enzyme responsible for phenol degradation was catechol 1, 2 dioxygenase. The optimal activity of catechol 1, 2 dioxygenase was observed at 500mg/L phenol concentration. The enzyme was purified 2.34 fold by ion exchange chromatography. The Km was found to be 5μmole with V_max of 62.5U/mg of protein. The optimal pH and temperature of the enzyme was 7.5 and 30℃ respectively. The enzyme activity was completely inhibited by Cu^++, Hg^++ and Fe^+++ metal ions. The SDS-PAGE analysis reveals that the enzyme has a molecular weight of 30k Dalton.
Catechol
Dioxygenase
Cite
Citations (25)
This chapter contains sections titled: Oxygenases Catechol 1,2-Dioxygenase Introduction Iron(III) Complexes as Structural and Functional Models for Catechol 1,2-Dioxygenases Mononuclear Iron(III) Precursor Complexes Mononuclear Iron(III) Tetrachlorocatecholate Complexes as Biomimetic Models for Enzyme Substrate Adducts Reactivity Studies of Iron(III) Catecholate Complexes Quercetin 2,3-Dioxygenase Introduction Results Kinetic Studies Copper Complexes as Structural Models for the Active Site of Quercetinase Spectroscopic Studies References
Catechol
Dioxygenase
Reactivity
Metalloprotein
Cite
Citations (2)
This study aimed to evaluate the environmental conditions for enzyme activity of catechol 1,2-dioxygenase (C1,2O) and catechol 2,3-dioxygenase (C2,3O) produced by Gordonia polyisoprenivorans in cell-free and immobilized extracts. The optimum conditions of pH, temperature, time course and effect of ions for enzyme activity were determined. Peak activity of C1,2O occurred at pH 8.0. The isolate exhibited the highest activity of C2,3O at pH 7.0 and 8.0 for the cell-free extract and immobilized extract, respectively. This isolate exhibited important characteristics such as broad range of pH, temperature and time course for enzyme activity.
Catechol
Dioxygenase
Cite
Citations (53)
Various picolinic acid derivatives were synthesized from ammonia and hydroxymuconic semialdehyde derivatives that were oxidatively prepared from various catechols by the action of Pseudomonas catechol 2,3-dioxygenase (C23O, metapyrocatechase).
Picolinic acid
Catechol
Dioxygenase
Catechol oxidase
Cite
Citations (28)
The Fe(II)- and alpha-ketoglutarate(alphaKG)-dependent dioxygenases have roles in synthesis of collagen and sensing of oxygen in mammals, in acquisition of nutrients and synthesis of antibiotics in microbes, and in repair of alkylated DNA in both. A consensus mechanism for these enzymes, involving (i) addition of O(2) to a five-coordinate, (His)(2)(Asp)-facially coordinated Fe(II) center to which alphaKG is also bound via its C-1 carboxylate and ketone oxygen; (ii) attack of the uncoordinated oxygen of the bound O(2) on the ketone carbonyl of alphaKG to form a bicyclic Fe(IV)-peroxyhemiketal complex; (iii) decarboxylation of this complex concomitantly with formation of an oxo-ferryl (Fe(IV)=O(2)(-)) intermediate; and (iv) hydroxylation of the substrate by the Fe(IV)=O(2)(-) complex via a substrate radical intermediate, has repeatedly been proposed, but none of the postulated intermediates occurring after addition of O(2) has ever been detected. In this work, an oxidized Fe intermediate in the reaction of one of these enzymes, taurine/alpha-ketoglutarate dioxygenase (TauD) from Escherichia coli, has been directly demonstrated by rapid kinetic and spectroscopic methods. Characterization of the intermediate and its one-electron-reduced form (obtained by low-temperature gamma-radiolysis of the trapped intermediate) by Mössbauer and electron paramagnetic resonance spectroscopies establishes that it is a high-spin, formally Fe(IV) complex. Its Mössbauer isomer shift is, however, significantly greater than those of other known Fe(IV) complexes, suggesting that the iron ligands in the TauD intermediate confer significant Fe(III) character to the high-valent site by strong electron donation. The properties of the complex and previous results on related alphaKG-dependent dioxygenases and other non-heme-Fe(II)-dependent, O(2)-activating enzymes suggest that the TauD intermediate is most probably either the Fe(IV)-peroxyhemiketal complex or the taurine-hydroxylating Fe(IV)=O(2)(-) species. The detection of this intermediate sets the stage for a more detailed dissection of the TauD reaction mechanism than has previously been reported for any other member of this important enzyme family.
Dioxygenase
Decarboxylation
Carboxylate
Reaction intermediate
Hydroxylation
Oxidative decarboxylation
Alpha ketoglutarate
Cite
Citations (683)
Catechol
Rhodococcus rhodochrous
Dioxygenase
Cite
Citations (10)
Rieske dioxygenases catalyze the cis-dihydroxylation of a wide range of aromatic compounds to initiate their biodegradation. The archetypal Rieske dioxygenase naphthalene 1,2-dioxygenase (NDOS) catalyzes dioxygenation of naphthalene to form (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. NDOS is composed of three proteins: a reductase, a ferredoxin, and an α3β3 oxygenase (NDO). In each α subunit, NDO contains a Rieske Fe2S2 cluster and a mononuclear iron site where substrate dihydroxylation occurs. NDOS also catalyzes monooxygenase reactions for many substrates. The mechanism of the reaction is unknown for either the mono- or dioxygenase reactions but has been postulated to involve direct reaction of either a structurally characterized Fe(III)−hydroperoxy intermediate or the electronically equivalent Fe(V)−oxo−hydroxo intermediate formed by O−O bond cleavage before reaction with substrate. The reaction for the former intermediate is expected to proceed through cationic intermediates, while the latter is anticipated to initially form a radical intermediate. Here the monooxygenation reactions of the diagnostic probe molecules, norcarane and bicyclohexane, are investigated. In each case, a significant amount of the rearrangement product derived from a radical intermediate (lifetime of 11−18 ns) is observed, while little or no ring expansion product from a cationic intermediate is formed. Thus, monooxygenation of these molecules appears to proceed via the Fe(V)−oxo−hydroxo intermediate. The formation of this high-valent intermediate shows that it must also be considered as a possible participant in the dioxygenation reaction, in contrast to computational studies but in accord with previous biomimetic studies.
Dioxygenase
Hydroxylation
Dihydroxylation
Reaction intermediate
Reactive intermediate
Cationic polymerization
Ribonucleotide reductase
Cite
Citations (110)
Intradiol aromatic ring-cleaving dioxygenases use an active site, nonheme Fe(3+) to activate O2 and catecholic substrates for reaction. The inability of Fe(3+) to directly bind O2 presents a mechanistic conundrum. The reaction mechanism of protocatechuate 3,4-dioxygenase is investigated here using the alternative substrate 4-fluorocatechol. This substrate is found to slow the reaction at several steps throughout the mechanistic cycle, allowing the intermediates to be detected in solution studies. When the reaction was initiated in an enzyme crystal, it was found to halt at one of two intermediates depending on the pH of the surrounding solution. The X-ray crystal structure of the intermediate at pH 6.5 revealed the key alkylperoxo-Fe(3+) species, and the anhydride-Fe(3+) intermediate was found for a crystal reacted at pH 8.5. Intermediates of these types have not been structurally characterized for intradiol dioxygenases, and they validate four decades of spectroscopic, kinetic, and computational studies. In contrast to our similar in crystallo crystallographic studies of an Fe(2+)-containing extradiol dioxygenase, no evidence for a superoxo or peroxo intermediate preceding the alkylperoxo was found. This observation and the lack of spectroscopic evidence for an Fe(2+) intermediate that could bind O2 are consistent with concerted formation of the alkylperoxo followed by Criegee rearrangement to yield the anhydride and ultimately ring-opened product. Structural comparison of the alkylperoxo intermediates from the intra- and extradiol dioxygenases provides a rationale for site specificity of ring cleavage.
Dioxygenase
Reaction intermediate
Cleavage (geology)
Bond cleavage
Catalytic cycle
Cite
Citations (41)
We report the structures of three intermediates in the O2 activation and insertion reactions of an extradiol ring-cleaving dioxygenase. A crystal of Fe2+-containing homoprotocatechuate 2,3-dioxygenase was soaked in the slow substrate 4-nitrocatechol in a low O2 atmosphere. The x-ray crystal structure shows that three different intermediates reside in different subunits of a single homotetrameric enzyme molecule. One of these is the key substrate-alkylperoxo-Fe2+ intermediate, which has been predicted, but not structurally characterized, in an oxygenase. The intermediates define the major chemical steps of the dioxygenase mechanism and point to a general mechanistic strategy for the diverse 2-His-1-carboxylate enzyme family.
Dioxygenase
Carboxylate
Reaction intermediate
Crystal (programming language)
Cite
Citations (372)
Catechol
Dioxygenase
Semiquinone
Cleavage (geology)
Reactivity
Cite
Citations (14)