title: Cloning of the phr gene and amplification of photolyase in Escherichia coli.
abstract: A new technique is developed for physically enriching recombinant DNA molecules in an in vitro recombination mixture. UV-irradiation of the donor DNA before recombination enables photoreactivating enzyme (PRE) (deoxyribodipyrimidine photolyase, EC 4.1.99.3) to attach to the donor segments in recombinant molecules. This attached protein causes retention of the recombinant molecules on a nitrocellulose filter, while molecules not containing donor DNA pass through. The bound DNA  is repaired of its UV damage and released for insertion into cells by exposure to photoreactivating light in situ, yielding approx. 350-fold enrichment. Although applicable to any gene, this procedure has been used in cloning the Escherichia coli phr gene itself, permitting 100-fold amplification of the gene product in vivo.
mesh_terms: D004260:DNA Repair; D004269:DNA, Bacterial / Q000528:radiation effects*; D004270:DNA, Circular / Q000528:radiation effects; D004274:DNA, Recombinant; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000528:radiation effects; D005796:Genes / Q000528:radiation effects; D008190:Lyases / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial; D004270:DNA, Circular; D004274:DNA, Recombinant; D008190:Lyases; D004255:Deoxyribodipyrimidine Photo-Lyase