Star activity

The star activity or star activity describes in molecular biology the ability of a restriction enzyme to bind to DNA other than the standard recognition sequences under special conditions and to cleave it there. Star activity thus lowers the selectivity of a DNA digest by the restriction enzyme and therefore represents a major problem in biotechnological processes. Star activity has been found for a large number of different restriction enzymes, including Eco RI , Eco RV , Hind III and Taq I , and can occur in particular when there are deviations from the standard conditions, for example with too high a glycerol concentration (> 5%), organic solvents, too high a pH value and an excessive enzyme concentration (> 100 U / µg DNA) or an excessively long exposure time.

literature

• Blanchard, A. et al. (2008): The Fidelity Index provides a systematic quantitation of star activity of DNA restriction endonucleases. In: Nucleic Acids Res. 36 (9): e50. PMID 18413342 doi : 10.1093 / nar / gkn182 PDF