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dc.contributor.authorRoca Moliner, María Teresa
dc.contributor.authorLiu, Hanbin
dc.contributor.authorMesser, Benjamin
dc.contributor.authorWarshel, Arieh
dc.date.accessioned2016-05-10T07:47:24Z
dc.date.available2016-05-10T07:47:24Z
dc.date.issued2007-12-25
dc.identifier.citationROCA MOLINER, María Teresa; LIU, Hanbin; MESSER, Benjamin; WARSHEL, Arieh. On the relationship between thermal stability and catalytic power of enzymes. Biochemistry (2007), v. 46, issue 51, pp. 15076-15088,ca_CA
dc.identifier.urihttp://hdl.handle.net/10234/159458
dc.description.abstractThe  possible  relationship  between  the  thermal  stability  and  the  catalytic  power  of  enzymes  is  of   great  current  interest.  In  particular,  it  has  been  suggested  that  thermophilic  or  hyperthermophilic   (Tm)   enzymes   have   lower   catalytic   power   at   a   given   temperature   than   the   corresponding   mesophilic   (Ms)   enzymes,   because   the   thermophilic   enzymes   are   less   flexible   (assuming   that   flexibility   and   catalysis   are   directly   correlated).   These   suggestions   presume   that   the   reduced   dynamics   of   the   thermophilic   enzymes   is   the   reason   for   their   reduced   catalytic   power.   The   present  paper  takes  the  specific  case  of  dihydrofolate  reductase  (DHFR) and explores the validity of the above argument by simulation approaches. It is found that the Tm enzymes have restricted motions in the direction of the folding coordinate, but this is not relevant to the chemical process, since the motions along the reaction coordinate are perpendicular to the folding motions. Moreover, it is shown that the rate of the chemical reaction is determined by the activation barrier and the corresponding reorganization energy, rather than by dynamics or flexibility in the ground state. In fact, as far as flexibility is concerned, we conclude that the displacement along the reaction coordinate is larger in the Tm enzyme than in the Ms enzyme and that the general trend in enzyme catalysis is that the best catalyst involves less motion during the reaction than the less optimal catalyst. The relationship between thermal stability and catalysis appears to reflect the fact that in order to obtain small electrostatic reorganization energy it is necessary to invest some folding energy in the overall preorganization process. Thus, the optimized catalysts are less stable. This trend is clearly observed in the DHFR case.ca_CA
dc.format.extent55 p.ca_CA
dc.format.mimetypeapplication/pdfca_CA
dc.language.isoengca_CA
dc.publisherACS Publicationsca_CA
dc.relation.isPartOfBiochemistry (2007), v. 46, issue 51ca_CA
dc.subjectThermal stabilityca_CA
dc.subjectEnzymesca_CA
dc.subjectCatalytic powerca_CA
dc.subjectDynamicsca_CA
dc.subjectDihydrofolate  reductase  (DHFR)ca_CA
dc.titleOn the relationship between thermal stability and catalytic power of enzymesca_CA
dc.typeinfo:eu-repo/semantics/articleca_CA
dc.identifier.doihttp://dx.doi.org/10.1021/bi701732a
dc.rights.accessRightsinfo:eu-repo/semantics/openAccessca_CA
dc.relation.publisherVersionhttp://pubs.acs.org/doi/abs/10.1021/bi701732aca_CA
dc.editionPreprintca_CA


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