Protein motions during catalysis by dihydrofolate reductases
نویسندگان
چکیده
منابع مشابه
Coupling of protein motions and hydrogen transfer during catalysis by Escherichia coli dihydrofolate reductase.
The enzyme DHFR (dihydrofolate reductase) catalyses hydride transfer from NADPH to, and protonation of, dihydrofolate. The physical basis of the hydride transfer step catalysed by DHFR from Escherichia coli has been studied through the measurement of the temperature dependence of the reaction rates and the kinetic isotope effects. Single turnover experiments at pH 7.0 revealed a strong dependen...
متن کاملHydride transfer during catalysis by dihydrofolate reductase from Thermotoga maritima.
DHFR (dihydrofolate reductase) catalyses the metabolically important reduction of 7,8-dihydrofolate by NADPH. DHFR from the hyperthermophilic bacterium Thermotoga maritima (TmDHFR), which shares similarity with DHFR from Escherichia coli, has previously been characterized structurally. Its tertiary structure is similar to that of DHFR from E. coli but it is the only DHFR characterized so far th...
متن کاملLoop interactions during catalysis by dihydrofolate reductase from Moritella profunda.
Dihydrofolate reductase (DHFR) is often used as a model system to study the relation between protein dynamics and catalysis. We have studied a number of variants of the cold-adapted DHFR from Moritella profunda (MpDHFR), in which the catalytically important M20 and FG loops have been altered, and present a comparison with the corresponding variants of the well-studied DHFR from Escherichia coli...
متن کاملCatalysis by dihydrofolate reductase and other enzymes arises from electrostatic preorganization, not conformational motions.
The proposal that enzymatic catalysis is due to conformational fluctuations has been previously promoted by means of indirect considerations. However, recent works have focused on cases where the relevant motions have components toward distinct conformational regions, whose population could be manipulated by mutations. In particular, a recent work has claimed to provide direct experimental evid...
متن کاملThe Role of Large-Scale Motions in Catalysis by Dihydrofolate Reductase
Dihydrofolate reductase has long been used as a model system to study the coupling of protein motions to enzymatic hydride transfer. By studying environmental effects on hydride transfer in dihydrofolate reductase (DHFR) from the cold-adapted bacterium Moritella profunda (MpDHFR) and comparing the flexibility of this enzyme to that of DHFR from Escherichia coli (EcDHFR), we demonstrate that fac...
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ژورنال
عنوان ژورنال: Philosophical Transactions of the Royal Society B: Biological Sciences
سال: 2006
ISSN: 0962-8436,1471-2970
DOI: 10.1098/rstb.2006.1865