Table 1.
Antimicrobial Agent | Sequence | Mass (Da) | Net Charge | MIC PM1 |
---|---|---|---|---|
LL-37 | LLGDFFRKSKEKIGKEFKRI-VQRIKDFLRNLVPRTES | 4493 | +6 | 4 |
Cecropin A | KWKLFKKIEKVGQNIRDGII-KAGPAVAVVGQATQIAK-NH2 | 4404 | +7 | 0.9 |
Melittin | GIGAVLKVLTTGLPALISWI-KRKRQQ-NH2 | 2846 | +6 | 5 |
β-peptide copolymer1 MM63:CHx37 | ~7000 | 63% cationic sidechains | 25 μg/mL | |
CM15 | KWKLFKKIGAVLKVL-NH2 | 1770 | +6 | 5 |
Minimum inhibitory concentration (in μM) against WT MG1655 E. coli over 6-hr period in aerated EZRDM medium at 30°C, determined by OD for successive two-fold dilutions in 96 well plates. Copolymer MM63:CHx37 lacks a defined molar mass, so MIC is in μg/mL. The molecular weight of an “average” copolymer is ~7 kDa. Average is 35 subunits long, with 37% CHx (cyclohexyl) and 63% MM (mono-methyl) sidechains; see Ref. 13 for details. Thus an MIC of 25 μg/mL corresponds to a molar concentration of about 4 μM.