Article

[Identification of the cardiac beta-adrenergic receptor protein: solubilization and purification by affinity chromatography].

Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme 11/2007; 52(13 Suppl):1782-3. DOI: 10.1073/pnas.69.10.2828
Source: PubMed

ABSTRACT A protein that binds catecholamines with a specificity parallel to that of their in vivo effects on cardiac contractility (isoproterenol > epinephrine or norepinephrine > dopamine > dihydroxyphenylalanine) was solubilized from a microsomal fraction of canine ventricular myocardium. The binding protein was purified 500 to 800-fold by solubilization and subsequent affinity chromatography with conjugates of norepinephrine linked to agarose beads. Purified beta-adrenergic binding protein exists in two forms, corresponding to molecular weights of 40,000 and 160,000. The purified material has a single association constant, 2.3 x 10(5) liters/mol (as compared to two association constants, 10(7) and 10(6) liters/mol, for the binding protein in particulate form) but retains the identical binding specificity for beta-adrenergic drugs and antagonists.

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