Any feedback?
Please rate this page
(enzyme.php)
(0/150)

BRENDA support

BRENDA Home
show all | hide all No of entries

Information on EC 1.14.18.1 - tyrosinase

for references in articles please use BRENDA:EC1.14.18.1
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
EC Tree
IUBMB Comments
A type III copper protein found in a broad variety of bacteria, fungi, plants, insects, crustaceans, and mammals, which is involved in the synthesis of betalains and melanin. The enzyme, which is activated upon binding molecular oxygen, can catalyse both a monophenolase reaction cycle (reaction 1) or a diphenolase reaction cycle (reaction 2). During the monophenolase cycle, one of the bound oxygen atoms is transferred to a monophenol (such as L-tyrosine), generating an o-diphenol intermediate, which is subsequently oxidized to an o-quinone and released, along with a water molecule. The enzyme remains in an inactive deoxy state, and is restored to the active oxy state by the binding of a new oxygen molecule. During the diphenolase cycle the enzyme binds an external diphenol molecule (such as L-dopa) and oxidizes it to an o-quinone that is released along with a water molecule, leaving the enzyme in the intermediate met state. The enzyme then binds a second diphenol molecule and repeats the process, ending in a deoxy state . The second reaction is identical to that catalysed by the related enzyme catechol oxidase (EC 1.10.3.1). However, the latter can not catalyse the hydroxylation or monooxygenation of monophenols.
Specify your search results
Select one or more organisms in this record: ?
Show additional data
Do not include text mining results
Include (text mining) results
Include results (AMENDA + additional results, but less precise)
Word Map
hide
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria, Archaea
Reaction Schemes
hide(Overall reactions are displayed. Show all >>)
L-tyrosine
+
O2
=
dopaquinone
+
H2O
+
=
+
2
L-dopa
+
O2
=
2
dopaquinone
+
2
H2O
2
+
=
2
+
2
Synonyms
tyrosinase, monophenolase, oxygen oxidoreductase, phenol oxidases, murine tyrosinase, melc2, o-diphenol oxidase, monophenol oxidase, met-tyrosinase, jrppo1, more