Polymerase Per Second:
Polymerase Per Second (or PoPS) is defined as the number of times that an RNA polymerase molecule passes a specific point on DNA per unit time (e.g., from the 3' end of a promoter part into the 5' end of a downstream part such as a ribosome binding site). PoPS are measured indirectly by introducing a test gene with the same regulatory region but with a CFP protein coding region and measuring the fluorescence. For more information please see the "Adventures in Synthetic Biology" comic.
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