Tyrosinases, which are widely distributed among animals, plants and fungi, are involved in many biologically essential functions, including pigmentation, sclerotization, primary immune response and host defence. In the present study, we present a structural and physicochemical characterization of two new tyrosinases from the crustaceans Palinurus elephas (European spiny lobster) and Astacus lep...

In this paper, sequences of six human tyrosinase, retrieved from Swiss Prot database are analyzed and characterized using In silico tools. Primary structure analysis shows that most of the tyrosinase are hydrophobic in nature due to the high content of non -polar residues. The presence of cysteines in the most of the tyrosinases sequences infer that these proteins may form disulphide (SS) bonds...

The complete cDNA sequence and protein reading frame of a developmentally regulated hemocyanin subunit in the Dungeness crab (Cancer magister) is presented. The protein sequence is aligned with 18 potentially homologous hemocyanin-type proteins displaying apparent sequence similarities. Functional domains are identified, and a comparison of predicted hydrophilicities, surface probabilities, and...

Catechol oxidase (EC 1.10.3.1), tyrosinase (EC 1.14.18.1), and laccase (EC 1.10.3.2) are copper-containing metalloenzymes. They oxidise substituted phenols and use molecular oxygen as a terminal electron acceptor. Catechol oxidases and tyrosinases catalyse the oxidation of p-substituted o-diphenols to the corresponding o-quinones. Tyrosinases also catalyse the introduction of a hydroxyl group i...

BACKGROUND AND AIMS Following previous findings of high extracellular redox activity in lichens and the presence of laccases in lichen cell walls, the work presented here additionally demonstrates the presence of tyrosinases. Tests were made for the presence of tyrosinases in 40 species of lichens, and from selected species their cellular location and molecular weights were determined. The effe...

Oculocutaneous albinism type 1 (OCA1) is an autosomal recessive disease resulting from mutations of the tyrosinase gene (TYR). To elucidate the molecular basis of OCA1 phenotypes, we analysed the early processing and maturation of several different types of mutant tyrosinase with various degrees of structural abnormalities (i.e. two large deletion mutants, two missense mutants that completely d...

Tyrosinases (monophenol, o-diphenol:oxygen oxidoreductase, EC (1.14.18.1) are copper-containg enzymes which catalyze the o-hydroxylation of monophenols and subsequent oxidation of o-diphenols to quinones. The enzymes are involved in the pigmentation and are important factors in wound healing and primary immune response. Tyrosinases are found in prokaryotic and eukaryotic microorganisms, in mamm...