Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Calicheamicin γ causes negative writhing of plasmid DNA. The effect of binding of calicheamicin γ (•) and esperamicin C (○) on the topology of negatively supercoiled pUC19 was determined by sucrose gradient centrifugation as described in Materials and Methods. The sedimentation of supercoiled pUC19 DNA was determined relative to nicked, open-circular pUC19.
