DC Field | Value | Language |
---|---|---|
dc.contributor.author | Choi, KY | - |
dc.contributor.author | Choi, G | - |
dc.contributor.author | Ha, NC | - |
dc.contributor.author | Kim, MS | - |
dc.contributor.author | Hong, BH | - |
dc.contributor.author | Oh, BH | - |
dc.date.accessioned | 2016-03-31T13:18:03Z | - |
dc.date.available | 2016-03-31T13:18:03Z | - |
dc.date.created | 2009-03-17 | - |
dc.date.issued | 2001-06-12 | - |
dc.identifier.issn | 0006-2960 | - |
dc.identifier.other | 2001-OAK-0000002032 | - |
dc.identifier.uri | https://oasis.postech.ac.kr/handle/2014.oak/19518 | - |
dc.description.abstract | Delta (5)-3-ketosteroid isomerase (KSI) from Pseudomonas putida Biotype B catalyzes the allylic isomerization of Delta (5)-3-ketosteroids to their conjugated Delta (4)-isomers via a dienolate intermediate. Two electrophilic catalysts, Tyr-14 and Asp-99, are involved in a hydrogen bond network that comprises Asp99 O delta2 . . .O of Wat504 . . . Tyr-14 O eta . . . Tyr-55 O eta . . . Tyr-30 O eta in the active site of P, putida KSI. Even though neither Tyr-30 nor Tyr-55 plays an essential role in catalysis by the KSI, the catalytic activity of Y14F could be increased ca. 26-51-fold by the additional Y30F and/or Y55F mutation in the hydrogen bond network. To identify the structural basis for the pseudoreversion in the KSI, crystal structures of Y14F and Y14F/Y30F/Y55F have been determined at 1.8 and 2.0 Angstrom resolution, respectively. Comparisons of the two structures near the catalytic center indicate that the hydrogen bond between Asp-99 O delta2 and C3-O of the steroid, which is perturbed by the Y14F mutation, can be partially restored to that in the wild-type enzyme by the additional Y30F/Y55F mutations. The kinetic parameters of the tyrosine mutants with the additional D99N or D99L mutation also support the idea that Asp-99 contributes to catalysis more efficiently in Y14F/Y30F/Y55F than in Y14F. In contrast to the catalytic mechanism of Y14F, the C4 proton of the steroid substrate was found to be transferred to the C6 position in Y14F/Y30F/Y55F with little exchange of the substrate 4 beta -proton with a solvent deuterium based on the reaction rate in D2O. Taken together, our findings strongly suggest that the improvement in the catalytic activity of Y14F by the additional Y30F/Y55F mutations is due to the changes in the structural integrity at the catalytic site and the resulting restoration of the proton-transfer mechanism in Y14F/Y30F/Y55F. | - |
dc.description.statementofresponsibility | X | - |
dc.language | English | - |
dc.publisher | AMER CHEMICAL SOC | - |
dc.relation.isPartOf | BIOCHEMISTRY | - |
dc.title | Pseudoreversion of the catalytic activity of Y14F by the additional substitution(s) of tyrosine with phenylalanine in the hydrogen bond network of Delta(5)-3-ketosteroid isomerase from Pseudomonas putida Biotype B | - |
dc.type | Article | - |
dc.contributor.college | 생명과학과 | - |
dc.identifier.doi | 10.1021/BI002767+ | - |
dc.author.google | Choi, G | - |
dc.author.google | Ha, NC | - |
dc.author.google | Kim, MS | - |
dc.author.google | Hong, BH | - |
dc.author.google | Oh, BH | - |
dc.author.google | Choi, KY | - |
dc.relation.volume | 40 | - |
dc.relation.issue | 23 | - |
dc.relation.startpage | 6828 | - |
dc.relation.lastpage | 6835 | - |
dc.contributor.id | 10052985 | - |
dc.relation.journal | BIOCHEMISTRY | - |
dc.relation.index | SCI급, SCOPUS 등재논문 | - |
dc.relation.sci | SCI | - |
dc.collections.name | Journal Papers | - |
dc.type.rims | ART | - |
dc.identifier.bibliographicCitation | BIOCHEMISTRY, v.40, no.23, pp.6828 - 6835 | - |
dc.identifier.wosid | 000169232300013 | - |
dc.date.tcdate | 2019-01-01 | - |
dc.citation.endPage | 6835 | - |
dc.citation.number | 23 | - |
dc.citation.startPage | 6828 | - |
dc.citation.title | BIOCHEMISTRY | - |
dc.citation.volume | 40 | - |
dc.contributor.affiliatedAuthor | Choi, KY | - |
dc.contributor.affiliatedAuthor | Kim, MS | - |
dc.contributor.affiliatedAuthor | Oh, BH | - |
dc.identifier.scopusid | 2-s2.0-0035849571 | - |
dc.description.journalClass | 1 | - |
dc.description.journalClass | 1 | - |
dc.description.wostc | 23 | - |
dc.description.scptc | 23 | * |
dc.date.scptcdate | 2018-05-121 | * |
dc.description.isOpenAccess | N | - |
dc.type.docType | Article | - |
dc.subject.keywordPlus | SECONDARY S96P MUTATION | - |
dc.subject.keywordPlus | 3-OXO-DELTA(5)-STEROID ISOMERASE | - |
dc.subject.keywordPlus | DELTA-5-3-KETOSTEROID ISOMERASE | - |
dc.subject.keywordPlus | KETOSTEROID ISOMERASE | - |
dc.subject.keywordPlus | TRIOSEPHOSPHATE ISOMERASE | - |
dc.subject.keywordPlus | CRYSTAL-STRUCTURE | - |
dc.subject.keywordPlus | SITE | - |
dc.subject.keywordPlus | MECHANISM | - |
dc.subject.keywordPlus | ENZYME | - |
dc.subject.keywordPlus | RESIDUES | - |
dc.relation.journalWebOfScienceCategory | Biochemistry & Molecular Biology | - |
dc.description.journalRegisteredClass | scie | - |
dc.description.journalRegisteredClass | scopus | - |
dc.relation.journalResearchArea | Biochemistry & Molecular Biology | - |
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