Biomaterial Database

Comparative temperature-stability properties of malate dehydrogenases from some thermophilic fungi. 1979

A S Wali, and A K Mattoo, and V V Modi

Temperature-activity and temperature-stability relationships of malate dehydrogenases from eight thermophilic fungi were determined. Temperature optima for maximum activity of the enzymes varied between 50 degrees and 60 degrees and the Arrhenius plots were linear between 5 degrees and 50 degrees. The energies of activation ranged from 2.1 Kcal/mol for the enzyme from Sporotrichum thermophile to 9.1 Kcal/mol for that from Penicillium duponti. Heat inactivation kinetics at 50 degrees revealed heat lability of the enzyme from most of the thermophilic fungi. The t1/2's (min) were less than 10 for the enzymes from P. duponti, S. thermophile and Thermoascus aurantiacus; less than 30 for those from Chaetomium thermophile var. coprophile, H. lanuginosa and C. thermophile var. dissitum; and greater than 30 for those from Mucor pusillus and H. insolens. Salts of Na+, K+ and NH4+, and citrate protected the enzymes from H. lanuginosa, C. thermophile var. dissitum and M. pusillus against heat inactivation.

UI	MeSH Term	Description	Entries
D008291	Malate Dehydrogenase	An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.	Malic Dehydrogenase,NAD-Malate Dehydrogenase,Dehydrogenase, Malate,Dehydrogenase, Malic,Dehydrogenase, NAD-Malate,NAD Malate Dehydrogenase
D002414	Cations, Monovalent	Positively charged atoms, radicals or group of atoms with a valence of plus 1, which travel to the cathode or negative pole during electrolysis.	Monovalent Cation,Cation, Monovalent,Monovalent Cations
D004355	Drug Stability	The chemical and physical integrity of a pharmaceutical product.	Drug Shelf Life,Drugs Shelf Lives,Shelf Life, Drugs,Drug Stabilities,Drugs Shelf Life,Drugs Shelf Live,Life, Drugs Shelf,Shelf Life, Drug,Shelf Live, Drugs,Shelf Lives, Drugs
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations
D005656	Fungal Proteins	Proteins found in any species of fungus.	Fungal Gene Products,Fungal Gene Proteins,Fungal Peptides,Gene Products, Fungal,Yeast Proteins,Gene Proteins, Fungal,Peptides, Fungal,Proteins, Fungal
D005658	Fungi	A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including MUSHROOMS; YEASTS; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.	Fungi, Filamentous,Molds,Filamentous Fungi,Filamentous Fungus,Fungus,Fungus, Filamentous,Mold
D006207	Half-Life	The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.	Halflife,Half Life,Half-Lifes,Halflifes
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures