Influence of cationic triphenylmethane dyes upon DNA polymerization and product hydrolysis by Escherichia coli polymerase I.

The cationic triphenylmethane dyes crystal violet, methyl green, and malachite green inhibited DNA synthesis catalyzed by Escherichia coli B polymerase I (polymerase I). Lower concentrations of the dyes inhibited DNA replication as a direct function of the proportion of AT to GC in the DNA of Clostridium perfringens, Escherichia coli, and Micrococcus lysodeikticus. When the intercalant proflavin was employed, the GC-rich micrococcal DNA was most severely inhibited. In addition, both the triphenylmethanes and proflavin inhibited product hydrolysis catalyzed by polymerase I.