kinase (redirected from protein k's)

kinase /ki·nase/ (ki´nās)

1. a subclass of the transferases, comprising the enzymes that catalyze the transfer of a high-energy group from a donor (usually ATP) to an acceptor.

2. a suffix used in the names of some enzymes that convert an inactive or precursor form.

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ki·nase (kns, -nz, kns, -z)

n.

1. An enzyme that catalyzes the conversion of a proenzyme to an active enzyme.

2. A various enzyme that catalyzes the transfer of a phosphate group from a donor, such as ADP or ATP, to an acceptor.

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kinase

[kī′nās]

Etymology: Gk, kinesis, motion; ase, enzyme

1 an enzyme that catalyzes the transfer of a phosphate group or another high-energy molecular group to an acceptor molecule. Each of these kinases is named for its receptor, such as acetate kinase, fructokinase, or hexokinase.

2 an enzyme that activates a preenzyme (zymogen). Each of these kinases is named for its source, such as bacterial kinase, enterokinase, fibrinokinase, insulin kinase, staphylokinase, streptokinase, streptokinase-streptodornase, or urokinase.

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kinase

1. a subclass of the transferases, comprising the enzymes that catalyze the transfer of a high-energy group from a donor (usually ATP) to an acceptor, and named, according to the acceptor, as creatine kinase, fructokinase, etc.

2. an enzyme that activates a zymogen, and named, according to its source, as enterokinase, streptokinase, etc.

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protein k's

cellular enzymes which utilize ATP to phosphorylate proteins, usually at a selected OH group of serine, threonine or tyrosine residue in the protein, so as to increase or decrease the activity of the protein.

protein kinase C

membrane bound protein kinase designated C because it requires Ca²+ and phosphatidyl serine for its activity. Activated by sn-1,2-diacylglycerol (DAG) produced from phosphatidyl inositol 4,5-bisphosphate. Phosphorylates target proteins such as the insulin receptor, β-adrenergic receptor, glucose transporter, HMG-CoA reductase, cytochrome P-450 and tyrosine hydroxylase.