Thermo Scientific™ phiX174 RF1 DNA

Prepare DNA molecular weight standards with Thermo Scientific™ phiX174 RF1 DNA, a 5386 bp double-stranded closed circular plasmid.

phiX174 was the first DNA virus discovered to have a single-stranded, circular genome. phiX174 DNA is 5386 nt in length. The DNA strand packaged into the virion is termed the plus strand. After entering the cell, the Thermo Scientific phiX174 DNA is used as a template for minus-strand synthesis, producing double-stranded DNA. The conversion of plus DNA strands to double-stranded DNA does not require any of the phage genes to function.

The double-stranded DNA can then be transcribed, resulting in synthesis of phage-encoded proteins. Synthesis of single-stranded (plus) DNA requires phage-encoded gene A protein. DNA synthesis is initiated at ori (+) and proceeds in the direction indicated. Late in infection, the single-stranded circles are encapsidated into new virions. The cycle terminates by cellular lysis, mediated by phage gene E encoded protein.