DC Field | Value | Language |
---|---|---|
dc.contributor.author | Jang, DS | - |
dc.contributor.author | Choi, G | - |
dc.contributor.author | Cha, HJ | - |
dc.contributor.author | Shin, S | - |
dc.contributor.author | Hong, BH | - |
dc.contributor.author | Lee, HJ | - |
dc.contributor.author | Lee, HC | - |
dc.contributor.author | Choi, KY | - |
dc.date.accessioned | 2017-07-19T12:43:11Z | - |
dc.date.available | 2017-07-19T12:43:11Z | - |
dc.date.created | 2016-01-15 | - |
dc.date.issued | 2015-05-31 | - |
dc.identifier.issn | 1016-8478 | - |
dc.identifier.uri | https://oasis.postech.ac.kr/handle/2014.oak/36318 | - |
dc.description.abstract | Low-barrier hydrogen bonds (LBHBs) have been proposed to have important influences on the enormous reaction rate increases achieved by many enzymes. Delta(5)-3-ketosteroid isomerase (KSI) catalyzes the allylic isomerization of Delta(5)-3-ketosteroid to its conjugated Delta(4)-isomers at a rate that approaches the diffusion limit. Tyr14, a catalytic residue of KSI, has been hypothesized to form an LBHB with the oxyanion of a dienolate steroid intermediate generated during the catalysis. The unusual chemical shift of a proton at 16.8 ppm in the nuclear magnetic resonance spectrum has been attributed to an LBHB between Tyr14 O eta and C3-O of equilenin, an intermediate analogue, in the active site of D38N KSI. This shift in the spectrum was not observed in Y30F/Y55F/D38N and Y30F/Y55F/Y115F/D38N mutant KSIs when each mutant was complexed with equilenin, suggesting that Tyr14 could not form LBHB with the intermediate analogue in these mutant KSIs. The crystal structure of Y30F/Y55F/Y115F/D38N-equilenin complex revealed that the distance between Tyr14 O eta and C3-O of the bound steroid was within a direct hydrogen bond. The conversion of LBHB to an ordinary hydrogen bond in the mutant KSI reduced the binding affinity for the steroid inhibitors by a factor of 8.1-11. In addition, the absence of LBHB reduced the catalytic activity by only a factor of 1.7-2. These results suggest that the amount of stabilization energy of the reaction intermediate provided by LBHB is small compared with that provided by an ordinary hydrogen bond in KSI. | - |
dc.language | English | - |
dc.publisher | KOREAN SOC MOLECULAR & CELLULAR BIOLOGY | - |
dc.relation.isPartOf | MOLECULES AND CELLS | - |
dc.title | Contribution of a Low-Barrier Hydrogen Bond to Catalysis Is Not Significant in Ketosteroid Isomerase | - |
dc.type | Article | - |
dc.identifier.doi | 10.14348/MOLCELLS.2015.2266 | - |
dc.type.rims | ART | - |
dc.identifier.bibliographicCitation | MOLECULES AND CELLS, v.38, no.5, pp.409 - 415 | - |
dc.identifier.wosid | 000355558800005 | - |
dc.date.tcdate | 2019-02-01 | - |
dc.citation.endPage | 415 | - |
dc.citation.number | 5 | - |
dc.citation.startPage | 409 | - |
dc.citation.title | MOLECULES AND CELLS | - |
dc.citation.volume | 38 | - |
dc.contributor.affiliatedAuthor | Lee, HC | - |
dc.contributor.affiliatedAuthor | Choi, KY | - |
dc.identifier.scopusid | 2-s2.0-84946407528 | - |
dc.description.journalClass | 1 | - |
dc.description.journalClass | 1 | - |
dc.description.wostc | 1 | - |
dc.description.scptc | 1 | * |
dc.date.scptcdate | 2018-05-121 | * |
dc.type.docType | Article | - |
dc.subject.keywordPlus | PUTIDA BIOTYPE-B | - |
dc.subject.keywordPlus | ACTIVE-SITE | - |
dc.subject.keywordPlus | DELTA(5)-3-KETOSTEROID ISOMERASE | - |
dc.subject.keywordPlus | 3-OXO-DELTA(5)-STEROID ISOMERASE | - |
dc.subject.keywordPlus | ENZYMATIC CATALYSIS | - |
dc.subject.keywordPlus | SERINE PROTEASES | - |
dc.subject.keywordPlus | DELTA-5-3-KETOSTEROID ISOMERASE | - |
dc.subject.keywordPlus | PSEUDOMONAS-TESTOSTERONI | - |
dc.subject.keywordPlus | CRYSTAL-STRUCTURE | - |
dc.subject.keywordPlus | TRANSITION-STATE | - |
dc.subject.keywordAuthor | enzyme catalysis | - |
dc.subject.keywordAuthor | ketosteroid isomerase | - |
dc.subject.keywordAuthor | low-barrier hydrogen bond | - |
dc.subject.keywordAuthor | Tyr14 | - |
dc.relation.journalWebOfScienceCategory | Biochemistry & Molecular Biology | - |
dc.relation.journalWebOfScienceCategory | Cell Biology | - |
dc.description.journalRegisteredClass | scie | - |
dc.description.journalRegisteredClass | scopus | - |
dc.description.journalRegisteredClass | kci | - |
dc.relation.journalResearchArea | Biochemistry & Molecular Biology | - |
dc.relation.journalResearchArea | Cell Biology | - |
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