Purification of Pyruyate Dehydrogenase Complex from an Extreme Thermophile , BtveMus ealdolytieuss - and Its Thermal Stability
نویسندگان
چکیده
(E2), and lipoamide dehydrogenase (E3) on the analogy of those from BbciVlas tearothermophilus. El and E3 were stable at pH 5.7-10.2 and 4.5-11.3, respectively. Halves of El and E3 activity were abolished by incubation for 30min at 65eC and 85eC, respectively. Loss of oyerall activity was principally due to inactiyation of El. Structural changes in the eomplex incubated st high temperature were studied by fluorescence spectroscopy. The results suggested that the thermal denaturation of the complex Proc)eeded threugh at Ieast two different s epe: inactivations of El and E3, and the former process is aceempanied by a reduction ef the complex siep.
منابع مشابه
Ancestral residues stabilizing 3-isopropylmalate dehydrogenase of an extreme thermophile: experimental evidence supporting the thermophilic common ancestor hypothesis.
Ancestral amino acid residues were inferred for 3-isopropylmalate dehydrogenase (IPMDH), and were introduced into the enzyme of an extreme thermophile, Sulfolobus sp. strain 7. The thermostability of the mutant enzymes was compared with that of the wild type enzyme. At least five of the seven mutants tested showed higher thermal stability than the wild type IPMDH. The results are compatible wit...
متن کاملFurther stabilization of 3-isopropylmalate dehydrogenase of an extreme thermophile, Thermus thermophilus, by a suppressor mutation method.
We succeeded in further improvement of the stability of 3-isopropylmalate dehydrogenase (IPMDH) from an extreme thermophile, Thermus thermophilus, by a suppressor mutation method. We previously constructed a chimeric IPMDH consisting of portions of thermophile and mesophile enzymes. The chimeric enzyme is less thermostable than the thermophile enzyme. The gene encoding the chimeric enzyme was s...
متن کاملHigh thermal stability of 3-isopropylmalate dehydrogenase from Thermus thermophilus resulting from low DeltaC(p) of unfolding.
To characterize the thermal stability of 3-isopropylmalate dehydrogenase (IPMDH) from an extreme thermophile, Thermus thermophilus, urea-induced unfolding of the enzyme and of its mesophilic counterpart from Escherichia coli was investigated at various temperatures. The unfolding curves were analyzed with a three-state model for E.coli IPMDH and with a two-state model for T.thermophilus IPMDH, ...
متن کاملAdaptation to extreme environments: macromolecular dynamics in complex systems.
What we previously thought of as insurmountable physical and chemical barriers to life, we now see as yet another niche harbouring 'extremophiles'. Extremophiles and their macromolecules had to develop molecular mechanisms of adaptation to extreme physico-chemical conditions. Using neutron spectroscopy, we have demonstrated that molecular dynamics represents one of these molecular mechanisms of...
متن کاملPurification and properties of Penicillium glucose 6-phosphate dehydrogenase.
1. Glucose 6-phosphate dehydrogenase was isolated and partially purified from a thermophilic fungus, Penicillium duponti, and a mesophilic fungus, Penicillium notatum. 2. The molecular weight of the P. duponti enzyme was found to be 120000+/-10000 by gelfiltration and sucrose-density-gradient-centrifugation techniques. No NADP(+)- or glucose 6-phosphate-induced change in molecular weight could ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2018