pro·mot·er   (prə-mō'tər)    n.   One that promotes, especially an active supporter or advocate. A financial and publicity organizer, as of a boxing match or an artistic performance. Genetics The region of an operon that acts as the initial binding site for RNA polymerase.

Main Entry: pro·mot·er
Function: noun
: one who alone or with others actively participates in the formation of a business or venture <promoters owe a fiduciary duty to the corporation they are promoting —Railroad C. Clark>

Main Entry: pro·mot·er
Pronunciation: -'mOt-&r
Function: noun
1 : a substance that in very small amounts is able to increase theactivity of a catalyst
2 : a binding site in a DNA chain at which RNA polymerase binds to initiate transcription of messenger RNA by one or more nearby structural genes
3 : a chemical believed to promote carcinogenicity or mutagenicity

promoter pro·mot·er (prə-mō'tər)
n.

1. A substance that increases the activity of a catalyst.

2. A DNA molecule to which RNA polymerase binds, initiating the transcription of mRNA.

3. A chemical that may promote carcinogenicity or mutagenicity.

promoter   (prə-mō'tər)  Pronunciation Key  The region of an operon that acts as the initial binding site for RNA polymerase.

promoter

in chemistry, substance added to a solid catalyst to improve its performance in a chemical reaction. By itself the promoter has little or no catalytic effect. Some promoters interact with active components of catalysts and thereby alter their chemical effect on the catalyzed substance. The interaction may cause changes in the electronic or crystal structures of the active solid component. Commonly used promoters are metallic ions incorporated into metals and metallic oxide catalysts, reducing and oxidizing gases or liquids, and acids and bases added during the reaction or to the catalysts before being used.

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