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Results for “Multifunctional Enzymes”

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At least 19 recordsLinked to original sources

PubMed2002

Crystallization and characterization of the dehydrogenase domain from rat peroxisomal multifunctional enzyme type 1.

Peroxisomal multifunctional enzyme type 1 from rat (perMFE-1) is a monomeric multidomain protein shown to have 2-enoyl-CoA hydratase/Delta(3)-Delta(2)-enoyl-CoA isomerase and (3S)-hydroxyacyl-CoA dehydrogenase domains followed by a C-terminal extension of 130 amino acids with unknown function apart from being a carrier of the peroxisomal targeting signal type 1. The truncated perMFE-1 without the N-terminal hydratase/isomerase domain (perMFE-1DH; residues 260-722) was overexpressed as an enzymatically active recombinant protein, purified and characterized. Using (3S)-hydroxydecanoyl-CoA as a substrate, the specific enzymatic activity of perMFE-1DH was determined to be 2.2 micromol min(-1) mg(-1), comparable with that of perMFE-1 purified from rat liver (2.8 micromol min(-1) mg(-1)). The protein was crystallized in the apo form by the hanging-drop method and a complete data set to 2.45 A resolution was collected using a rotating-anode X-ray source. The crystals have primitive tetragonal symmetry, with unit-cell parameters a = b = 125.9, c = 60.2 A.

3-Hydroxyacyl CoA Dehydrogenases↗

PubMed1988

Synthesis of beauvericin by a multifunctional enzyme.

Beauvericin synthetase, a multifunctional enzyme catalyzing depsipeptide formation in Beauveria bassiana was purified to near homogeneity. The enzyme consists of a single polypeptide chain with a molecular mass of about 250 kdaltons. The mechanism of beauvericin formation is very similar to that of the cyclohexadepsipeptide enniatin. The constituents of the beauvericin molecule, L-phenylalanine and D-alpha-hydroxyisovaleric acid are activated as thioesters via the corresponding adenylates. N-Methylation takes place at the thioester bound stage of the phenylalanine residues. Omission of the methyl donor S-adenosyl-L-methionine results in the formation of demethylbeauvericin. Studies on substrate specificity revealed that phenylalanine could be replaced by a number of other aromatic or aliphatic amino acids like beta-phenylserine, ortho-, meta-, para-fluorophenylalanine, isoleucine, norleucine and leucine. Valine, the constituent amino acid of enniatin B was not accepted by the enzyme.

Anti-Bacterial Agents↗

PubMed2002

Treatment of multifunctional enzymes in metabolic pathway analysis.

In metabolic pathway analysis, it should be considered that many enzymes operate with low specificity (e.g. nucleoside diphosphokinase, uridine kinase, transketolase, aldolase), so that various substrates and products can be converted. Here, we analyze the effect of enzymes with low substrate specificity on the elementary flux modes (pathways). We also study the benefits of two different approaches to describing multifunctional enzymes. The usual description is in terms of (overall) enzymatic reactions. At a more detailed level, the reaction steps (half-reactions, hemi-reactions) of the formation and conversion of enzyme-substrate complexes are considered. Multifunctional enzymes operate according to various mechanisms. This is illustrated here by the reaction schemes for the different enzyme mechanisms of bifunctional enzymes. For enzymes with two or more functions, it is important to consider only linearly independent functions, because otherwise cyclic elementary modes would occur which do not perform any net transformation. However, the choice of linearly independent functions is not a priori unique. We give a method for making this choice unique by considering the extreme pathways of the hemi-reactions system. A formal application of the algorithm for computing elementary flux modes (pathways) yields the result that the number of such modes sometimes depend on the level of description if some reactions are reversible and the products of the multifunctional enzymes are external metabolites or some multifunctional enzymes partly share the same metabolites. However, this problem can be solved by appropriate interpretation of the definition of elementary modes and the correct choice of independent functions of multifunctional enzymes. The analysis is illustrated by a biochemical example taken from nucleotide metabolism, comparing the two ways of description for nucleoside diphosphokinase and adenylate kinase, and by several smaller examples.

Adenylate Kinase↗

PubMed2000

Engineering a living cell to desired metabolite concentrations and fluxes: pathways with multifunctional enzymes.

With molecular genetics enabling modulation of the concentrations of cellular enzymes, metabolic engineering becomes limited by the question of which modulations of the enzyme concentrations are required to bring about a desired pattern of cellular metabolism. In an earlier paper (Kholodenko et al. (1998). Biotechnol. Bioeng. 59, 239-247) we derived a method to determine the required modulations. This method, however, cannot be immediately applied to cellular pathways with enzymes catalyzing more than one step in metabolism (multifunctional enzymes). In the present paper we show to which extent the presence of multifunctional enzymes limits biotechological ambitions, which one might otherwise pursue in vain. In particular, it is impossible to change the concentration of a single intermediate and leave the rest of metabolism unperturbed if that intermediate interacts directly with a multifunctional enzyme. The analytical machinery of Metabolic Control Analysis is used to relate the desired and ensuing changes in the metabolic pattern. An explicit solution to this problem of engineering metabolism is then given in the form of a single matrix equation.

Animals↗

PubMed2001

Characterization of the promoter region of the human peroxisomal multifunctional enzyme type 2 gene.

Peroxisomal multifunctional enzyme type 2 (perMFE-2) catalyzes conversion of (24E)-3alpha,7alpha, 12alpha-trihydroxy-5beta-cholest-24-enoyl-CoA to (24-keto)-3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoyl-CoA, which are physiological intermediates in cholic acid synthesis. In contrast to long chain fatty acid oxidizing enzymes clofibrate does not induce peroxisomal enzymes metabolizing bile acid intermediates. We proposed the existence of PPAR-independent regulation of cholesterol side chain oxidation in the process of bile acid synthesis. In the present study, we characterized the promoter region of the human perMFE-2 gene. The promoter contains the Sp1/AP2 binding site (-151/-142) within 197 base pairs upstream of the translation start site. Mutation of the Sp1/AP2 binding site decreases the promoter activity. Analysis by the luciferase assay revealed that the activity of the promoter region is strong in HepG2 and HeLa cell lines, although the activity in HepG2 cells was five- to sixfold higher than that in HeLa cells. Transient transfection assays have confirmed that AP2alpha and AP2gamma were able to transactivate the perMFE-2 promoter/luciferase chimeric gene. Cotransfections with Sp1 expression plasmid decreased the promoter activity. We suggest that perMFE-2 promoter activity is the result of both the abundance of AP2 and Sp1 family members and their relative ratios.

3-Hydroxyacyl CoA Dehydrogenases↗

PubMed1977

Methylenetetrahydrofolate dehydrogenase, methenyltetrahydrofolate cyclohydrolase and formyltetrahydrofolate synthetase from porcine liver. Isolation of a dehydrogenase-cyclohydrolase fragment from the multifunctional enzyme.

Tryptic digestion of a multifunctional enzyme from porcine liver containing methylenetetrahydrofolate dehydrogenase (5,10-methylenetetrahydrofolate: NADP+ oxidoreductase, EC 1.5.1.5), methenyltetrahydrofolate cyclohydrolase (5,10-methenyltetrahydrofolate 5-hydrolase, EC 3.5.4.9) and formyltetrahydrofolate synthetase (formate:tetrahydrofolate ligase, EC 6.3.4.3) activities destroys the synthetase. A fragment containing both dehydrogenase and cyclohydrolase activities has been isolated by affinity chromatography on an NADP+-Sepharose affinity column. The purified fragment is homogeneous on dodecyl sulfate-polyacrylamide gel electrophoresis where its molecular weight was determined as 33 000 +/- 1200 compared with 100 000 for the undigested protein. The cyclohydrolase activity retains sensitivity to inhibition by NADP+, MgATP and ATP.

Aminohydrolases↗

PubMed2000

Substrate specificities of peroxisomal members of short-chain alcohol dehydrogenase superfamily: expression and characterization of dehydrogenase part of Candida tropicalis multifunctional enzyme.

In addition to several other enzymes, the short-chain alcohol dehydrogenase superfamily includes a group of peroxisomal multifunctional enzymes involved in fatty acid and cholesterol side-chain beta-oxidation. Mammalian peroxisomal multifunctional enzyme type 2 (perMFE-2) is a 2-enoyl-CoA hydratase-2/(R)-3-hydroxyacyl-CoA dehydrogenase. As has been shown previously, perMFE-2 hydrates (24E)-3alpha,7alpha, 12alpha-trihydroxy-5beta-cholest-24-enoyl-CoA to (24R, 25R)-3alpha, 7alpha,12alpha,24xi-tetrahydroxy-5beta-choles tanoyl-CoA, which has been characterized as a physiological intermediate in cholic acid synthesis. Out of four possible stereoisomers of 3alpha,7alpha, 12alpha,24xi-tetrahydroxy-5beta-cholestanoyl-CoA , the mammalian perMFE-2 dehydrogenates only the (24R,25R)-isomer. The yeast peroxisomal multifunctional enzyme (MFE) was first described as 2-enoyl-CoA hydratase-2/(R)-3-hydroxyacyl-CoA dehydrogenase. To investigate the stereospecificity of yeast peroxisomal MFE, the two dehydrogenase domains of C. tropicalis MFE were expressed in E. coli as a 65 kDa recombinant protein. This protein catalyzes the dehydrogenation of straight-chain (R)-3-hydroxyacyl-CoAs, but it is devoid of (S)-3-hydroxyacyl-CoA dehydrogenase and 2-enoyl-CoA hydratase activities. The protein dehydrogenates (24R,25R)- and (24R, 25S)-isomers of 3alpha,7alpha, 12alpha, 24xi-tetrahydroxy-5beta-cholestanoyl-CoA. Interestingly, the protein also shows 17beta-estradiol dehydrogenase activity. As a monofunctional (R)-specific 3-hydroxyacyl-CoA dehydrogenase is currently unavailable, this recombinant enzyme can be used to study the stereochemistry of bile acid synthesis.

3-Hydroxyacyl CoA Dehydrogenases↗

PubMed2006

Regulation of SIRT 1 mediated NAD dependent deacetylation: a novel role for the multifunctional enzyme CD38.

The SIRT 1 enzyme is a NAD dependent deacetylase implicated in ageing, cell protection, and energy metabolism in mammalian cells. How the endogenous activity of SIRT 1 is modulated is not known. The enzyme CD38 is a multifunctional enzyme capable of synthesis of the second messenger, cADPR, NAADP, and ADPR. However, the major enzymatic activity of CD38 is the hydrolysis of NAD. Of particular interest is the fact that CD38 is present on the inner nuclear membrane. Here, we investigate the modulation of the SIRT 1 activity by CD38. We propose that by modulating availability of NAD to the SIRT1 enzyme, CD38 may regulate SIRT1 enzymatic activity. We observed that in CD38 knockout mice, tissue levels of NAD are significantly increased. We also observed that incubation of purified recombinant SIRT1 enzyme with CD38 or nuclear extracts of wild-type mice led to a significant inhibition of its activity. In contrast, incubation of SIRT1 with cellular extract from CD38 knockout mice was without effect. Furthermore, the endogenous activity of SIRT1 was several time higher in nuclear extracts from CD38 knockout mice when compared to wild-type nuclear extracts. Finally, the in vivo deacetylation of the SIRT1 substrate P53 is increased in CD38 knockout mice tissue. Our data support the novel concept that nuclear CD38 is a major regulator of cellular/nuclear NAD level, and SIRT1 activity. These findings have strong implications for understanding the basic mechanisms that modulate intracellular NAD levels, energy homeostasis, as well as ageing and cellular protection modulated by the SIRT enzymes.

ADP-ribosyl Cyclase 1↗

PubMed1981

Enzymic conversion of agmatine to putrescine in Lathyrus sativus seedlings. Purification and properties of a multifunctional enzyme (putrescine synthase).

The participation of a multifunctional enzyme (a single polypeptide with multiple catalytic activities (14)) has been demonstrated in the conversion of agmatine to putrescine in Lathyrus sativus seedlings. This enzyme (putrescine synthase) with inherent activities of agmatine iminohydrolase, putrescine transcarbamylase, ornithine transcarbamylase, and carbamate kinase has been purified to homogeneity and has Mr = 55,000. In the presence of inorganic phosphate, the enzyme catalyzed the stoichiometric conversion of agmatine and ornithine to putrescine and citrulline, respectively. The different activities associated with the enzyme copurified with near constancy in their specific activity. The enzyme catalyzed phosphorolysis and arsenolysis of N-carbamyl putrescine. The multifunctionality of putrescine synthase was also supported by 1) activity staining, 2) intact transfer of the ureido-14C group from labeled NJ-carbamyl putrescine to ornithine to form citrulline, and 3) the affinity of the enzyme toward structurally and functionally related affinity matrices. An agmatine cycle is proposed wherein N-carbamyl putrescine arising from the agmatine iminohydrolase reaction is converted to putrescine and citrulline, with the ureido group of N-carbamyl putrescine being transferred intact to ornithine. Preliminary results indicate that this series of reactions is also present in other plants.

Agmatine↗

PubMed1994

Purification and characterization of multifunctional enzyme from mouse liver peroxisomes.

A simple and rapid purification procedure for hepatic peroxisomal multifunctional enzyme (delta 3, delta 2-enoyl-CoA isomerase/enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase) from clofibrate treated mice is described. The purification is achieved within two days using ion-exchange chromatography and an easily prepared affinity resin. The overall yield is 10% or more after a 100-fold enrichment from the cytosolic fraction of liver tissue. The native enzyme is a monomer with a molecular mass of 75 kDa. The protein is blocked in the N-terminus but internal amino acid sequences was obtained after proteolytic cleavage. Western blot analysis indicated proteolysis of multifunctional enzyme in different subcellular fractions derived from liver tissue. The hydratase activity of the enzyme is heat-labile and highly dependent on the concentration of Tris buffer or potassium chloride present. Optimal activity was found around 37 degrees C and pH 7. The enzyme also shows dehydrogenase and isomerase activity.

3-Hydroxyacyl CoA Dehydrogenases↗

PubMed2006

Crystal structure of yeast peroxisomal multifunctional enzyme: structural basis for substrate specificity of (3R)-hydroxyacyl-CoA dehydrogenase units.

(3R)-hydroxyacyl-CoA dehydrogenase is part of multifunctional enzyme type 2 (MFE-2) of peroxisomal fatty acid beta-oxidation. The MFE-2 protein from yeasts contains in the same polypeptide chain two dehydrogenases (A and B), which possess difference in substrate specificity. The crystal structure of Candida tropicalis (3R)-hydroxyacyl-CoA dehydrogenase AB heterodimer, consisting of dehydrogenase A and B, determined at the resolution of 2.2A, shows overall similarity with the prototypic counterpart from rat, but also important differences that explain the substrate specificity differences observed. Docking studies suggest that dehydrogenase A binds the hydrophobic fatty acyl chain of a medium-chain-length ((3R)-OH-C10) substrate as bent into the binding pocket, whereas the short-chain substrates are dislocated by two mechanisms: (i) a short-chain-length 3-hydroxyacyl group ((3R)-OH-C4) does not reach the hydrophobic contacts needed for anchoring the substrate into the active site; and (ii) Leu44 in the loop above the NAD(+) cofactor attracts short-chain-length substrates away from the active site. Dehydrogenase B, which can use a (3R)-OH-C4 substrate, has a more shallow binding pocket and the substrate is correctly placed for catalysis. Based on the current structure, and together with the structure of the 2-enoyl-CoA hydratase 2 unit of yeast MFE-2 it becomes obvious that in yeast and mammalian MFE-2s, despite basically identical functional domains, the assembly of these domains into a mature, dimeric multifunctional enzyme is very different.

3-Hydroxyacyl CoA Dehydrogenases↗

PubMed1982

Enniatin synthetase, a novel type of multifunctional enzyme catalyzing depsipeptide synthesis in Fusarium oxysporum.

Enniatin synthetase, a multifunctional enzyme catalyzing depsipeptide formation in Fusarium oxysporum was purified to 98% homogeneity as judged by analytical disc gel electrophoresis. The enzyme consists of a single polypeptide chain of a molecular weight of about 250 000. Similar to a number of peptide synthetases and to fatty acid synthetase the enzyme contains 4'-phosphopantetheine as a prosthetic group. Studies on substrate specificity revealed that the enzyme is capable of synthesizing enniatins A--C and also mixed-type enniatins containing more than one species of amino acid. A linear dependence of rate of enniatin synthesis on enzyme concentration was observed, indicating that depsipeptide formation is an intramolecular process. Omission of the methyl donor S-adenosyl-L-methionine resulted in the formation of unmethylated enniatins with a reaction rate of about 10% of that observed in the case of enniatins. Sulfhydryl-directed reagents generally had an inhibitory influence on enniatin synthesis. However, inhibition studies with iodoacetamide revealed that it behaves differently toward the hydroxy acid site(s) and amino acid site(s). This indicates the presence of chemically distinct thiol groups in the active sites for the two substrates.

Amino Acids↗

PubMed2000

Mutational analysis of the N-methyltransferase domain of the multifunctional enzyme enniatin synthetase.

N-Methylcyclopeptides like cyclosporins and enniatins are synthesized by multifunctional enzymes representing hybrid systems of peptide synthetases and S-adenosyl-l-methionine (AdoMet)-dependent N-methyltransferases. The latter constitute a new family of N-methyltransferases sharing high homology within procaryotes and eucaryotes. Here we describe the mutational analysis of the N-methyltransferase domain of enniatin synthetase from Fusarium scirpi to gain insight into the assembly of the AdoMet-binding site. The role of four conserved motifs (I, (2085)VLEIGTGSGMIL; II/Y, (2105)SYVGLDPS; IV, (2152)DLVVFNSVVQYFTPPEYL; and V, (2194)ATNGHFLAARA) in cofactor binding as measured by photolabeling was studied. Deletion of the first 21 N-terminal amino acid residues of the N-methyltransferase domain did not affect AdoMet binding. Further shortening close to motif I resulted in loss of binding activity. Truncation of 38 amino acids from the C terminus and also internal deletions containing motif V led to complete loss of AdoMet-binding activity. Point mutations converting the conserved Tyr(223) (corresponding to position 2106 in enniatin synthetase) in motif II/Y (close to motif I) into Val, Ala, and Ser, respectively, strongly diminished AdoMet binding, whereas conversion of this residue to Phe restored AdoMet-binding activity to approximately 70%, indicating that Tyr(223) is important for AdoMet binding and that the aromatic Tyr(223) may be crucial for AdoMet binding in N-methylpeptide synthetases.

Amino Acid Motifs↗

PubMed1993

Molecular characterization of the enniatin synthetase gene encoding a multifunctional enzyme catalysing N-methyldepsipeptide formation in Fusarium scirpi.

The gene encoding the multifunctional enzyme enniatin synthetase from Fusarium scirpi (esyn1) was isolated and characterized by transcriptional mapping and expression studies in Escherichia coli. This is the first example of a gene encoding an N-methyl peptide synthetase. The nucleotide sequence revealed an open reading frame of 9393 bp encoding a protein of 3131 amino acids (M(r) 346,900). Two domains designated EA and EB within the protein were identified which share similarity to each other and to microbial peptide synthetase domains. In contrast to the N-terminal domain EA, the carboxyl terminal domain EB is interrupted by a 434-amino-acid portion which shows local similarity to a motif apparently conserved within adenine and cytosine RNA and DNA methyltransferases and therefore seems to harbour the N-methyl-transferase function of the multienzyme.

Amino Acid Sequence↗

PubMed1999

Molecular cloning and functional expression of gibberellin 2- oxidases, multifunctional enzymes involved in gibberellin deactivation.

A major catabolic pathway for the gibberellins (GAs) is initiated by 2beta-hydroxylation, a reaction catalyzed by 2-oxoglutarate-dependent dioxygenases. To isolate a GA 2beta-hydroxylase cDNA clone we used functional screening of a cDNA library from developing cotyledons of runner bean (Phaseolus coccineus L.) with a highly sensitive tritium-release assay for enzyme activity. The encoded protein, obtained by heterologous expression in Escherichia coli, converted GA9 to GA51 (2beta-hydroxyGA9) and GA51-catabolite, the latter produced from GA51 by further oxidation at C-2. The enzyme thus is multifunctional and is best described as a GA 2-oxidase. The recombinant enzyme also 2beta-hydroxylated other C19-GAs, although only GA9 and GA4 were converted to the corresponding catabolites. Three related cDNAs, corresponding to gene sequences present in Arabidopsis thaliana databases, also encoded functional GA 2-oxidases. Transcripts for two of the Arabidopsis genes were abundant in upper stems, flowers, and siliques, but the third transcript was not detected by Northern analysis. Transcript abundance for the two most highly expressed genes was lower in apices of the GA-deficient ga1-2 mutant of Arabidopsis than in wild-type plants and increased after treatment of the mutant with GA3. This up-regulation of GA 2-oxidase gene expression by GA contrasts GA-induced down-regulation of genes encoding the biosynthetic enzymes GA 20-oxidase and GA 3beta-hydroxylase. These mechanisms would serve to maintain the concentrations of biologically active GAs in plant tissues.

Amino Acid Sequence↗

PubMed1997

Recombinant 2-enoyl-CoA hydratase derived from rat peroxisomal multifunctional enzyme 2: role of the hydratase reaction in bile acid synthesis.

Rat liver peroxisomes contain two multifunctional enzymes: (1) perMFE-1 [2-enoyl-CoA hydratase 1/Delta3,Delta2-enoyl-CoA isomerase/(S)-3-hydroxyacyl-CoA dehydrogenase] and (2) perMFE-2 [2-enoyl-CoA hydratase 2/(R)-3-hydroxyacyl-CoA dehydrogenase]. To investigate the role of the hydratase activity of perMFE-2 in beta-oxidation, a truncated version of perMFE-2 was expressed in Escherichia coli as a recombinant protein. The protein catalyses the hydration of straight-chain (2E)-enoyl-CoAs to (3R)-hydroxyacyl-CoAs, but it is devoid of hydratase 1 [(2E)-enoyl-CoA to (3S)-hydroxyacyl-CoA] and (3R)-hydroxyacyl-CoA dehydrogenase activities. The purified enzyme (46 kDa hydratase 2) can be stored as an active enzyme for at least half a year. The recombinant enzyme hydrates (24E)-3alpha,7alpha,12alpha-trihydroxy- 5beta-cholest-24-enoyl-CoA to (24R,25R)-3alpha,7alpha,12alpha, 24-tetrahydroxy-5beta-cholestanoyl-CoA, which has previously been characterized as a physiological intermediate in bile acid synthesis. The stereochemistry of the products indicates that the hydration reaction catalysed by the enzyme proceeds via a syn mechanism. A monofunctional 2-enoyl-CoA hydratase 2 has not been observed as a wild-type protein. The recombinant 46 kDa hydratase 2 described here survives in a purified form under storage, thus being the first protein of this type amenable to application as a tool in metabolic studies.

3-Hydroxyacyl CoA Dehydrogenases↗

PubMed2004

Crystal structure of 2-enoyl-CoA hydratase 2 from human peroxisomal multifunctional enzyme type 2.

2-Enoyl-CoA hydratase 2 is the middle part of the mammalian peroxisomal multifunctional enzyme type 2 (MFE-2), which is known to be important in the beta-oxidation of very-long-chain and alpha-methyl-branched fatty acids as well as in the synthesis of bile acids. Here, we present the crystal structure of the hydratase 2 from the human MFE-2 to 3A resolution. The three-dimensional structure resembles the recently solved crystal structure of hydratase 2 from the yeast, Candida tropicalis, MFE-2 having a two-domain subunit structure with a C-domain complete hot-dog fold housing the active site, and an N-domain incomplete hot-dog fold housing the cavity for the aliphatic acyl part of the substrate molecule. The ability of human hydratase 2 to utilize such bulky compounds which are not physiological substrates for the fungal ortholog, e.g. CoA esters of C26 fatty acids, pristanic acid and di/trihydroxycholestanoic acids, is explained by a large hydrophobic cavity formed upon the movements of the extremely mobile loops I-III in the N-domain. In the unliganded form of human hydratase 2, however, the loop I blocks the entrance of fatty enoyl-CoAs with chain-length >C8. Therefore, we expect that upon binding of substrates bulkier than C8, the loop I gives way, contemporaneously causing a secondary effect in the CoA-binding pocket and/or active site required for efficient hydration reaction. This structural feature would explain the inactivity of human hydratase 2 towards short-chain substrates. The solved structure is also used as a tool for analyzing the various inactivating mutations, identified among others in MFE-2-deficient patients. Since hydratase 2 is the last functional unit of mammalian MFE-2 whose structure has been solved, the organization of the functional units in the biologically active full-length enzyme is also discussed.

Amino Acid Sequence↗

PubMed2003

Binary structure of the two-domain (3R)-hydroxyacyl-CoA dehydrogenase from rat peroxisomal multifunctional enzyme type 2 at 2.38 A resolution.

The crystal structure of (3R)-hydroxyacyl-CoA dehydrogenase of rat peroxisomal multifunctional enzyme type 2 (MFE-2) was solved at 2.38 A resolution. The catalytic entity reveals an alpha/beta short chain alcohol dehydrogenase/reductase (SDR) fold and the conformation of the bound nicotinamide adenine dinucleotide (NAD(+)) found in other SDR enzymes. Of great interest is the separate COOH-terminal domain, which is not seen in other SDR structures. This domain completes the active site cavity of the neighboring monomer and extends dimeric interactions. Peroxisomal diseases that arise because of point mutations in the dehydrogenase-coding region of the MFE-2 gene can be mapped to changes in amino acids involved in NAD(+) binding and protein dimerization.

3-Hydroxyacyl CoA Dehydrogenases↗