Characterization of three protein components required for functional reconstitution of the epoxide carboxylase multienzyme complex from Xanthobacter strain Py2

  title={Characterization of three protein components required for functional reconstitution of the epoxide carboxylase multienzyme complex from Xanthobacter strain Py2},
  author={J. Allen and S. Ensign},
  journal={Journal of Bacteriology},
  pages={3110 - 3115}
Epoxide carboxylase from Xanthobacter strain Py2 catalyzes the reductant- and NAD+-dependent carboxylation of aliphatic epoxides to beta-keto acids. Epoxide carboxylase from Xanthobacter strain Py2 has been resolved from cell extracts by anion-exchange chromatography into three protein components, designated I, II, and III, that are obligately required for functional reconstitution of epoxide carboxylase activity. Component II has been purified to homogeneity on the basis of its ability to… Expand
Purification to Homogeneity and Reconstitution of the Individual Components of the Epoxide Carboxylase Multiprotein Enzyme Complex fromXanthobacter Strain Py2*
The molecular weights, N-terminal sequences, and amino acid compositions of the purified epoxide carboxylase components were determined and found to correlate with open reading frames within and adjacent to a cloned fragment of DNA that complements Xanthobacter Py2 mutants defective in epoxide degradation. Expand
Structure based mechanistic studies on 2-ketopropyl coenzyme M oxidoreductase / carboxylase from Xanthobacter autotrophicus and [FeFe] hydrogenase from Clostridium pasteurianum
X-ray crystallography was employed to probe the mechanism of the enzyme 2ketopropyl coenzymeM oxidoreductase / carboxylase (2-KPCC). We were able to determine the enzyme structure in variousExpand
A role for coenzyme M (2-mercaptoethanesulfonic acid) in a bacterial pathway of aliphatic epoxide carboxylation.
A newfound versatility for coenzyme M as a carrier and activator of alkyl groups longer in chain-length than methane, a function for coENzyme M in a catabolic pathway of hydrocarbon oxidation, and the presence of coen enzyme M in the bacterial domain of the phylogenetic tree are evince. Expand
Roles of the Redox-Active Disulfide and Histidine Residues Forming a Catalytic Dyad in Reactions Catalyzed by 2-Ketopropyl Coenzyme M Oxidoreductase/Carboxylase
A mechanism of catalysis for 2-KPCC employing a unique hydrophobic active-site architecture promoting thioether bond cleavage and enolacetone formation not seen for other DSOR enzymes is interpreted and rationalized. Expand
Mechanism of Inhibition of Aliphatic Epoxide Carboxylation by the Coenzyme M Analog 2-Bromoethanesulfonate*
Results identify BES as a reactive CoM analog that specifically alkylates the interchange thiol that facilitates thioether bond cleavage and enolacetone formation during catalysis. Expand
New roles for CO2 in the microbial metabolism of aliphatic epoxides and ketones
New roles for CO2 as a cosubstrate in the metabolism of two classes of important xenobiotic compounds are identified and two new classes of carboxylases have been identified that promise to reveal new insights into biological strategies for the fixation of CO2 to organic substrates. Expand
Identification and Characterization of Epoxide Carboxylase Activity in Cell Extracts of Nocardia corallina B276
  • Jeffrey R. Allen, S. Ensign
  • Biology, Medicine
  • Journal of bacteriology
  • 1998
A common pathway of epoxyalkane metabolism for phylogenetically distinct bacteria that involves CO2 fixation and the activity of a multicomponent epoxide carboxylase enzyme system is suggested. Expand
Purification of a GlutathioneS-Transferase and a Glutathione Conjugate-Specific Dehydrogenase Involved in Isoprene Metabolism in Rhodococcussp. Strain AD45
The results suggest that the initial steps in isoprene metabolism are a monooxygenase-catalyzed conversion to isopren monoxide, a GST-catalystzed conjugation to HGMB, and a dehydrogenase-Catalyzed two-step oxidation to 2-glutathionyl-2-methyl-3-butenoic acid. Expand
Epoxyalkane:Coenzyme M Transferase in the Ethene and Vinyl Chloride Biodegradation Pathways of Mycobacterium Strain JS60
ABSTRACT Mycobacterium strains that grow on ethene and vinyl chloride (VC) are widely distributed in the environment and are potentially useful for biocatalysis and bioremediation. The catabolicExpand
Mechanistic implications of the structure of the mixed-disulfide intermediate of the disulfide oxidoreductase, 2-ketopropyl-coenzyme M oxidoreductase/carboxylase.
The structure of the mixed, enzyme-cofactor disulfide intermediate of ketopropyl-coenzyme M oxidoreductase/carboxylase has been determined by X-ray diffraction methods and insights into the stabilization of intermediates, substrate carboxylation, and product release are provided. Expand


Purification and characterization of two components of epoxypropane isomerase/carboxylase from Xanthobacter Py2.
NADPH was found to replace the need for a low-M(r), fraction in epoxypropane degradation assays containing components A and B and NAD+. Expand
A novel type of pyridine nucleotide-disulfide oxidoreductase is essential for NAD+- and NADPH-dependent degradation of epoxyalkanes by Xanthobacter strain Py2
A key protein encoded by a DNA fragment complementing a Xanthobacter strain Py2 mutant unable to degrade epoxides was purified and analyzed, and it was found that NADP-dependent protein is essential for epoxide degradation. Expand
Aliphatic and chlorinated alkenes and epoxides as inducers of alkene monooxygenase and epoxidase activities in Xanthobacter strain Py2
  • S. Ensign
  • Medicine, Chemistry
  • Applied and environmental microbiology
  • 1996
The inducible nature of the alkene oxidation system of Xanthobacter strain Py2 has been investigated and it was revealed that the 43-, 53-, and 57-kDa proteins, as well as two additional polypeptides, were newly synthesized upon exposure of cells to propylene or propylene oxide. Expand
Characterization of an Iron-Sulfur Flavoprotein from Methanosarcina thermophila *
Ferredoxin stimulated the CO-dependant reduction of Isf by the CO dehydrogenase·acetyl-CoA synthase complex that suggested ferredoxin is a physiological electron donor to Isf. Expand
Complementation of Xanthobacter Py2 mutants defective in epoxyalkane degradation, and expression and nucleotide sequence of the complementing DNA fragment.
Three Xanthobacter Py2 mutants (M3, M8 and M10) lacking epoxyalkane-degrading activity were isolated and characterized, and Surprisingly, M10 transformed with complementing cosmid pEP9 showed a constitutively expressed epoxyalksane- degraders activity, which was not observed in the wild-type strain. Expand
Carboxylation of Epoxides to b-Keto Acids in Cell Extracts of
A novel enzymatic reaction involved in the metabolism of aliphatic epoxides by Xanthobacter strain Py2 isExpand
Involvement of an ATP-dependent carboxylase in a CO2-dependent pathway of acetone metabolism by Xanthobacter strain Py2
Together, these studies provide the first demonstration of a CO2-dependent pathway of acetone metabolism for a strictly aerobic bacterium and provide direct evidence for the involvement of an ATP-dependent carboxylase in bacterial acet one metabolism. Expand
Carbon dioxide fixation in the metabolism of propylene and propylene oxide by Xanthobacter strain Py2
It is proposed that propylene oxide metabolism in Xanthobacter strain Py2 proceeds by terminal carboxylation of an isomerization intermediate, which, in the absence of CO2, is released as acetone. Expand
Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4
Using an improved method of gel electrophoresis, many hitherto unknown proteins have been found in bacteriophage T4 and some of these have been identified with specific gene products. Four majorExpand
Genetic toxicity of some important epoxides.
Determination of the rad-equivalence of genetic risks, i.e. the use of corresponding risks from a unit dose of ionizing radiation as a standard, indicates that the risks associated with Threshold Limit Values for epoxides in work environments in Western countries are 1–2 orders of magnitude higher than permissible risks for radiological workers. Expand