DNA-LIGASE IS ASSOCIATED WITH THE 21-S-COMPLEX OF ENZYMES FOR DNA-SYNTHESIS IN HELA-CELLS

Approximately 80% of the DNA ligase activity in HeLa cell extracts is associated with the 21 S enzyme complex that functions in simian virus 40 DNA replication in vitro (Malkas at al., Biochemistry 29, 6362 - 6 374., 1990). The DNA ligase associated with the 21 S complex was purif ied extensively and its physical, enzymic and immunological properties characterized as DNA ligase I. The association of DNA ligase I with t he 21 S complex of enzymes for DNA synthesis provides evidence for the physiological function; of this DNA ligase in DNA replication in huma n cells.