論文 - 詳細
| RRC ID | 53611 |
|---|---|
| 著者 | Wang J, Nemeria NS, Chandrasekhar K, Kumaran S, Arjunan P, Reynolds S, Calero G, Brukh R, Kakalis L, Furey W, Jordan F. |
| タイトル | Structure and function of the catalytic domain of the dihydrolipoyl acetyltransferase component in Escherichia coli pyruvate dehydrogenase complex. |
| ジャーナル | J Biol Chem |
| Abstract |
The Escherichia coli pyruvate dehydrogenase complex (PDHc) catalyzing conversion of pyruvate to acetyl-CoA comprises three components: E1p, E2p, and E3. The E2p is the five-domain core component, consisting of three tandem lipoyl domains (LDs), a peripheral subunit binding domain (PSBD), and a catalytic domain (E2pCD). Herein are reported the following. 1) The x-ray structure of E2pCD revealed both intra- and intertrimer interactions, similar to those reported for other E2pCDs. 2) Reconstitution of recombinant LD and E2pCD with E1p and E3p into PDHc could maintain at least 6.4% activity (NADH production), confirming the functional competence of the E2pCD and active center coupling among E1p, LD, E2pCD, and E3 even in the absence of PSBD and of a covalent link between domains within E2p. 3) Direct acetyl transfer between LD and coenzyme A catalyzed by E2pCD was observed with a rate constant of 199 s(-1), comparable with the rate of NADH production in the PDHc reaction. Hence, neither reductive acetylation of E2p nor acetyl transfer within E2p is rate-limiting. 4) An unprecedented finding is that although no interaction could be detected between E1p and E2pCD by itself, a domain-induced interaction was identified on E1p active centers upon assembly with E2p and C-terminally truncated E2p proteins by hydrogen/deuterium exchange mass spectrometry. The inclusion of each additional domain of E2p strengthened the interaction with E1p, and the interaction was strongest with intact E2p. E2p domain-induced changes at the E1p active site were also manifested by the appearance of a circular dichroism band characteristic of the canonical 4'-aminopyrimidine tautomer of bound thiamin diphosphate (AP). |
| 巻・号 | 289(22) |
| ページ | 15215-30 |
| 公開日 | 2014-5-30 |
| DOI | 10.1074/jbc.M113.544080 |
| PII | S0021-9258(20)38585-9 |
| PMID | 24742683 |
| PMC | PMC4140881 |
| MeSH | Acetyl Coenzyme A / biosynthesis Acetylation Amino Acid Sequence Carbohydrate Metabolism / physiology Catalytic Domain Crystallography, X-Ray Deuterium Exchange Measurement Dihydrolipoyllysine-Residue Acetyltransferase / chemistry Dihydrolipoyllysine-Residue Acetyltransferase / genetics Dihydrolipoyllysine-Residue Acetyltransferase / metabolism* Enzyme Activation / physiology Escherichia coli / enzymology* Escherichia coli / genetics Escherichia coli Proteins / chemistry Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Molecular Sequence Data Plasmids Pyruvate Dehydrogenase Complex / chemistry Pyruvate Dehydrogenase Complex / genetics Pyruvate Dehydrogenase Complex / metabolism* Pyruvic Acid / metabolism |
| IF | 4.238 |
| 引用数 | 23 |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 各媒体での言及数の合計 | 0 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 原核生物(大腸菌) | |