FIG. 3.

Retardation of CRE by wild-type (wt) and mutant CcpA. Purified CcpA and HPr-Ser-P were combined with a 26mer oligonucleotide containing CRE as indicated above the lanes. Numbers indicate the position of the amino acid substitution in each CcpA mutant. Samples were incubated at 37°C for 10 min prior to loading and run on a non-denaturing 5% polyacrylamide gel. DNA was visualized with ethidium bromide.