3'-end labeling of DNA with [alpha-32P]cordycepin-5'-triphosphate

Gene. 1980 Jul;10(2):177-83. doi: 10.1016/0378-1119(80)90135-3.


Cordycepin-5'-triphosphate (3'-deoxyadenosine-5'-triphosphate) can be incorporated into the 3'-ends of DNA fragments using terminal deoxynucleotidyl transferase from calf thymus (Bollum, 1974). Because cordycepin-5'-monophosphate lacks a 3'-OH group, only a single residue is incorporated. Furthermore, DNA molecules that contain cordycepin-5'-monophosphate at their 3'-ends become resistant to hydrolysis by exonucleases that require free 3'-OH ends. As an alternative to 5'-end labeling of complementary DNA strands, we have used [32P]cordycepin-5'-triphosphate labeling of 3'-ends to confirm the nucleotide sequence of a HhaI-endonuclease-generated pTU4-plasmid DNA fragment that contains several hot spots for insertions of the transposable genetic element Tn3. 3'-End labeling with [32P] cordycepin-5'-triphosphate has also proved useful in determining the sequence of the pTU4 DNA in the vicinity of a strategically located SstII endonuclease cleavage site in the replication region of the plasmid.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Attachment Sites, Microbiological
  • Base Sequence*
  • DNA Nucleotidyltransferases
  • DNA Transposable Elements
  • DNA, Bacterial / metabolism*
  • DNA, Circular
  • Deoxyadenine Nucleotides / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics
  • Methods
  • Phosphorus Radioisotopes
  • Plasmids


  • DNA Transposable Elements
  • DNA, Bacterial
  • DNA, Circular
  • Deoxyadenine Nucleotides
  • Phosphorus Radioisotopes
  • 3'-deoxyadenosine 5'-triphosphate
  • DNA Nucleotidyltransferases

Associated data

  • GENBANK/M10569
  • GENBANK/M10589