Biomaterial Database

Characterization of dimethylargininase from bovine brain: evidence for a zinc binding site. 1998

R Bogumil, and M Knipp, and S M Fundel, and M Vasák

Biochemisches Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.

Dimethylargininase (EC 3.5.3.18) is involved in the regulation of the levels of the natural occurring free arginine derivatives L-Nomega,Nomega-dimethylarginine and L-Nomega-methylarginine, which are reversible inhibitors of nitric oxide synthase. A dimethylargininase has been isolated from bovine brain tissue and was characterized by using immunological, kinetic, and spectroscopic techniques. Western blot analysis using polyclonal antibodies revealed that the enzyme is widely distributed in bovine with the highest relative concentrations found in brain and kidney tissue. A similar tissue distribution has also been reported for the other so far isolated dimethylargininase from rat kidney [Ogawa, T., Kimoto, M., and Sasaoka, K. (1989) J. Biol. Chem. 264, 10205-10209]. The bovine enzyme is a monomeric, globular protein (molecular mass approximately 31.2 kDa) containing one tightly bound Zn2+ ion, which can be removed by dialysis against 1,10-phenanthroline. The determination of kinetic constants for both the native (holo-protein) and the zinc-depleted (apo-protein) enzyme at 37 degrees ¿C established that the dimethylargininase is not a zinc hydrolase. The specific activity was 0.66 unit/mg for the holo-protein and 0.19 unit/mg for the apo-protein. The secondary structure determination of the native enzyme by circular dichroism revealed 41% alpha-helix and 32% beta-sheet and beta-turn structure. In the apo-enzyme, a small, but significant decrease in the alpha-helical content (5%) was observed, consistent with a marked decrease in enzymatic activity to 30%. Upon preincubation of both enzyme forms at 50 degrees C, only the holo-enzyme showed a residual enzymatic activity. In thermostability studies, a 7 degrees C lower apparent Tm value was observed for the apo-enzyme compared to the 66 degrees C for the holo-enzyme, suggesting that the zinc ion has a structure-stabilizing role. Besides the tightly bound zinc, additional Zn2+ ions inhibit the enzyme competitively with a Ki value of 2.0 microM. A possible interrelationship between dimethylargininase and nitric oxide synthase is discussed.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002942	Circular Dichroism	A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Circular Dichroism, Vibrational,Dichroism, Circular,Vibrational Circular Dichroism
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D004795	Enzyme Stability	The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.	Enzyme Stabilities,Stabilities, Enzyme,Stability, Enzyme
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D006867	Hydrolases	Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.	Hydrolase
D000581	Amidohydrolases	Any member of the class of enzymes that catalyze the cleavage of amide bonds and result in the addition of water to the resulting molecules.	Amidases,Amidohydrolase