scholarly journals Identification and characterization of the 2-enoyl-CoA hydratases involved in peroxisomal β-oxidation in rat liver

1997 ◽  
Vol 321 (1) ◽  
pp. 253-259 ◽  
Author(s):  
Martine DIEUAIDE-NOUBHANI ◽  
Dmitry NOVIKOV ◽  
Joël VANDEKERCKHOVE ◽  
Paul P. Van VELDHOVEN ◽  
Guy P. MANNAERTS

In this study we attempted to determine the number of 2-enoyl-CoA hydratases involved in peroxisomal β-oxidation. We therefore separated peroxisomal proteins from rat liver on several chromatographic columns and measured hydratase activities on the eluates with different substrates. The results indicate that rat liver peroxisomes contain two hydratase activities: (1) a hydratase activity associated with multifunctional protein 1 (MFP-1) (2-enoyl-CoA hydratase/Δ3,Δ2-enoyl-CoA isomerase/l-3-hydroxyacyl-CoA dehydrogenase) and (2) a hydratase activity associated with MFP-2 (17β-hydroxysteroid dehydrogenase/d-3-hydroxyacyl-CoA dehydrogenase/2-enoyl-CoA hydratase). MFP-1 forms and dehydrogenates l-3-hydroxyacyl-CoA species, whereas MFP-2 forms and dehydrogenates d-3-hydroxyacyl-CoA species. A portion of MFP-2 is proteolytically cleaved, most probably in the peroxisome, into a 34 kDa 17β-hydroxysteroid dehydrogenase/d-3-hydroxyacyl-CoA dehydrogenase and a 45 kDa d-specific 2-enoyl-CoA hydratase. Finally, the results confirm that MFP-1 is involved in the degradation of straight-chain fatty acids, whereas MFP-2 and its cleavage products seem to be involved in the degradation of the side chain of cholesterol (bile acid synthesis)

1997 ◽  
Vol 328 (2) ◽  
pp. 377-382 ◽  
Author(s):  
Yong-Mei QIN ◽  
M. Antti HAAPALAINEN ◽  
Demara CONRY ◽  
A. Dean CUEBAS ◽  
J. Kalervo HILTUNEN ◽  
...  

Rat liver peroxisomes contain two multifunctional enzymes: (1) perMFE-1 [2-enoyl-CoA hydratase 1/Δ3,Δ2-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 β-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)-3α,7α,12α-trihydroxy- 5β-cholest-24-enoyl-CoA to (24R,25R)-3α,7α,12α,24-tetrahydroxy-5β-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.


2002 ◽  
Vol 363 (3) ◽  
pp. 801-807 ◽  
Author(s):  
Dean A. CUEBAS ◽  
Christopher PHILLIPS ◽  
Werner SCHMITZ ◽  
Ernst CONZELMANN ◽  
Dmitry K. NOVIKOV

According to current views, the second peroxisomal β-oxidation pathway is responsible for the degradation of the side chain of bile acid intermediates. Peroxisomal multifunctional enzyme type 2 [peroxisomal multifunctional 2-enoyl-CoA hydratase/(R)-3-hydroxyacyl-CoA dehydrogenase; MFE-2] catalyses the second (hydration) and third (dehydrogenation) reactions of the pathway. Deficiency of MFE-2 leads to accumulation of very-long-chain fatty acids, 2-methyl-branched fatty acids and C27 bile acid intermediates in plasma, but bile acid synthesis is not blocked completely. In this study we describe an alternative pathway, which allows MFE-2 deficiency to be overcome. The alternative pathway consists of α-methylacyl-CoA racemase and peroxisomal multifunctional enzyme type 1 [peroxisomal multifunctional 2-enoyl-CoA hydratase/(S)-3-hydroxyacyl-CoA dehydrogenase; MFE-1]. (24E)-3α,7α,12α-Trihydroxy-5β-cholest-24-enoyl-CoA, the presumed physiological isomer, is hydrated by MFE-1 with the formation of (24S,25S)-3α,7α,12α,24-tetrahydroxy-5β-cholestanoyl-CoA [(24S,25S)-24-OH-THCA-CoA], which after conversion by a α-methylacyl-CoA racemase into the (24S,25R) isomer can again be dehydrogenated by MFE-1 to 24-keto-3α,7α,12α-trihydroxycholestanoyl-CoA, a physiological intermediate in cholic acid synthesis. The discovery of the alternative pathway of cholesterol side-chain oxidation will improve diagnosis of peroxisomal deficiencies by identification of serum 24-OH-THCA-CoA diastereomer profiles.


1997 ◽  
Vol 325 (2) ◽  
pp. 367-373 ◽  
Author(s):  
Martine DIEUAIDE-NOUBHANI ◽  
Stanny ASSELBERGHS ◽  
Guy P. MANNAERTS ◽  
Paul P. VAN VELDHOVEN

The second (enoyl-CoA hydratase) and third (3-hydroxyacyl-CoA dehydrogenase) steps of peroxisomal β-oxidation are catalysed by two separate multifunctional proteins (MFPs), MFP-1 being involved in the degradation of straight-chain fatty acids and MFP-2 in the β-oxidation of the side chain of cholesterol (bile acid synthesis). In the present study we determined which of the two MFPs is involved in the peroxisomal degradation of pristanic acid by using the synthetic analogue 2-methylpalmitic acid. The four stereoisomers of 3-hydroxy-2-methylpalmitoyl-CoA were separated by gas chromatography after hydrolysis, methylation and derivatization of the hydroxy group with (S)-2-phenylpropionic acid, and the stereoisomers were designated I–IV according to their order of elution from the column. Purified MFP-1 dehydrated stereoisomer IV but dehydrogenated stereoisomer III, so by itself MFP-1 is not capable of converting a branched enoyl-CoA into a 3-ketoacyl-CoA. In contrast, MFP-2 dehydrated and dehydrogenated the same stereoisomer (II), so it is highly probable that MFP-2 is involved in the peroxisomal degradation of branched fatty acids and that stereoisomer II is the physiological intermediate in branched fatty acid oxidation. By analogy with the results obtained with the four stereoisomers of the bile acid intermediate varanoyl-CoA, stereoisomer II can be assigned the 3R-hydroxy, 2R-methyl configuration.


1981 ◽  
Vol 89 (3) ◽  
pp. 406-417 ◽  
Author(s):  
MK Reddy ◽  
SA Qreshi ◽  
PF Hollenberg ◽  
JK Reddy

Peroxisome proliferators, which induce proliferation of hepatic peroxisomes, have been shown previously to cause a marked increase in an 80,000 mol wt polypeptide predominantly in the light mitochondrial and microsomal fractions of liver of rodents. We now present evidence to show that this hepatic peroxisome-proliferation-associated polypeptide, referred to as polypeptide PPA-80, is immunochemically identical with the multifunctional peroxisome protein displaying heat-labile enoyl-CoA hydratase activity. This conclusion is based on the following observations: (a) the purified polypeptide PPA-80 and the heat- labile enoyl-CoA hydratase from livers of rats treated with the peroxisome proliferators Wy-14,643 {[4-chloro-6(2,3-xylidino)-2-pyrimidinylthio]acetic acid} exhibit identical minimum molecular weights of approximately 80,000 on SDS polyacrylamide gel electrophoresis; (b) these two proteins are immunochemically identical on the basis of ouchterlony double diffusion, immunotitration, rocket immunoelectrophoresis, and crossed immunoelectrophoresis analysis; and (c) the immunoprecipitates formed by antibodies to polypeptide PPA-80 when dissociated on a sephadex G-200 column yield enoyl-CoA hydratase activity. Whether the polypeptide PPA-80 exhibits the activity of other enzyme(s) of the peroxisomal β-oxidation system such as fatty acyl-CoA oxidase activity or displays immunochemical identity with such enzymes remains to be determined. The availability of antibodies to polypeptide PPA-80 and enoyl-CoA hydratase facilitated immunofluorescent and immunocytochemical localization of the polypeptide PPA- 80 and enoyl-CoA hydratase in the rat liver. The indirect immunofluorescent studies with these antibodies provided direct visual evidence for the marked induction of polypeptide PPA-80 and enoyl-CoA hydratase in the livers of rats treated with Wy-14,643. The present studies also provide immunocytochemical evidence for the localization of polypeptide PPA- 80 and the heat-labile enoyl-CoA hydratase in the peroxisome, but not in the mitochondria, of hepatic parenchymal cells. These studies, therefore, provide morphological evidence for the existence of fatty acyl-CoA oxidizing system in peroxisomes. An increase of polypeptide PPA-80 on SDS polyacrylamide gel electrophoretic analysis of the subcellular fractions of liver of rodents treated with lipid-lowering drugs should serve as a reliable and sensitive indicator of enhanced peroxisomal β- oxidation system.


2020 ◽  
Vol 61 (11) ◽  
pp. 1450-1463 ◽  
Author(s):  
Solenne Marion ◽  
Lyne Desharnais ◽  
Nicolas Studer ◽  
Yuan Dong ◽  
Matheus D. Notter ◽  
...  

Bile acids, which are synthesized from cholesterol by the liver, are chemically transformed along the intestinal tract by the gut microbiota, and the products of these transformations signal through host receptors, affecting overall host health. These transformations include bile acid deconjugation, oxidation, and 7α-dehydroxylation. An understanding of the biogeography of bile acid transformations in the gut is critical because deconjugation is a prerequisite for 7α-dehydroxylation and because most gut microorganisms harbor bile acid transformation capacity. Here, we used a coupled metabolomic and metaproteomic approach to probe in vivo activity of the gut microbial community in a gnotobiotic mouse model. Results revealed the involvement of Clostridium scindens in 7α-dehydroxylation, of the genera Muribaculum and Bacteroides in deconjugation, and of six additional organisms in oxidation (the genera Clostridium, Muribaculum, Bacteroides, Bifidobacterium, Acutalibacter, and Akkermansia). Furthermore, the bile acid profile in mice with a more complex microbiota, a dysbiosed microbiota, or no microbiota was considered. For instance, conventional mice harbor a large diversity of bile acids, but treatment with an antibiotic such as clindamycin results in the complete inhibition of 7α-dehydroxylation, underscoring the strong inhibition of organisms that are capable of carrying out this process by this compound. Finally, a comparison of the hepatic bile acid pool size as a function of microbiota revealed that a reduced microbiota affects host signaling but not necessarily bile acid synthesis. In this study, bile acid transformations were mapped to the associated active microorganisms, offering a systematic characterization of the relationship between microbiota and bile acid composition.


1992 ◽  
Vol 40 (2) ◽  
pp. 446-448 ◽  
Author(s):  
Yasumasa KOIBUCHI ◽  
Junji YAMADA ◽  
Takafumi WATANABE ◽  
Takao KUROSAWA ◽  
Sadahiko TOHMA ◽  
...  

2010 ◽  
Vol 192 (19) ◽  
pp. 5053-5062 ◽  
Author(s):  
Shengli Dong ◽  
Sylvia A. McPherson ◽  
Yun Wang ◽  
Mei Li ◽  
Pengfei Wang ◽  
...  

ABSTRACT Bacillus anthracis spores, the etiological agents of anthrax, possess a loosely fitting outer layer called the exosporium that is composed of a basal layer and an external hairlike nap. The filaments of the nap are formed by trimers of the collagenlike glycoprotein BclA. Multiple pentasaccharide and trisaccharide side chains are O linked to BclA. The nonreducing terminal residue of the pentasaccharide side chain is the unusual sugar anthrose. A plausible biosynthetic pathway for anthrose biosynthesis has been proposed, and an antABCD operon encoding four putative anthrose biosynthetic enzymes has been identified. In this study, we genetically and biochemically characterized the activities of these enzymes. We also used mutant B. anthracis strains to determine the effects on BclA glycosylation of individually inactivating the genes of the anthrose operon. The inactivation of antA resulted in the appearance of BclA pentasaccharides containing anthrose analogs possessing shorter side chains linked to the amino group of the sugar. The inactivation of antB resulted in BclA being replaced with only trisaccharides, suggesting that the enzyme encoded by the gene is a dTDP-β-l-rhamnose α-1,3-l-rhamnosyl transferase that attaches the fourth residue of the pentasaccharide side chain. The inactivation of antC and antD resulted in the disappearance of BclA pentasaccharides and the appearance of a tetrasaccharide lacking anthrose. These phenotypes are entirely consistent with the proposed roles for the antABCD-encoded enzymes in anthrose biosynthesis. Purified AntA was then shown to exhibit β-methylcrotonyl-coenzyme A (CoA) hydratase activity, as we predicted. Similarly, we confirmed that purified AntC had aminotransferase activity and that purified AntD displayed N-acyltransferase activity.


2013 ◽  
Vol 82 (2) ◽  
pp. 216-229 ◽  
Author(s):  
Shiva Bhowmik ◽  
David H. Jones ◽  
Hsien‐Po Chiu ◽  
In‐Hee Park ◽  
Hsiu‐Ju Chiu ◽  
...  

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