|Products||Calf Topoisomerase I from USB Corp.|
|Item||Calf Topoisomerase I|
|Description|| Source: Calf thymus |
Topoisomerase I relaxes both positively and negatively supercoiled DNA by a transient breakage and rejoining of phosphodiester bonds(1,2). Relaxing supercoiled DNA with Topoisomerase I allows molecules to be differentiated by a single nucleotide pair by gel electrophoresis(3). Topoisomerase I is active in the absence of Mn2+ and can be used in solutions containing EDTA.
Tested for contaminating endonucleases and exonucleases.
20mM potassium phosphate (pH 7.2), 50mM KCl, 0.05mM EDTA, 5mM 2-mercaptoethanol, 0.02% BSA, 50% glycerol.
Shipping and Storage:
Shipped on dry ice. Store at -20C.
One unit is the amount of enzyme required to catalyze the conversion of 0.5 g supercoiled pBR322 DNA to a relaxed state in 30 min at 37C.
Applications:*Analysis of DNA supercoiling and conformation(2) .
*Produces knots in single-stranded, circular DNA(2).
*Analysis of chromatin reconstitution in vitro(4).
*DNA repair studies(4).
*Studies on drug resistance, cell proliferation and leukemia(5,6).
|Info|| USB Corp.|
26111 Miles Road
Cleveland Ohio 44128
Fax Number: 216.464.5075
Web Site: http://www.usbweb.com