A strategy for analyzing a database of antimicrobial peptides shows promise for the computer design of new, more potent antimicrobials—in particular, peptides that kill methicillin-resistant Staphylococcus aureus (MRSA). Guangshun Wang and Biswajit Mishra of the University of Nebraska Medical Center describe a filtering method for generating compounds from their lab’s antimicrobial peptide database. They use a series of filters to select promising combinations of properties—including peptide length, hydrophobicity, and structure—to design peptides with highly tailored bacteria-killing traits (J. Am. Chem. Soc., DOI: 10.1021/ja305644e). The method has already borne fruit: Wang’s group recently designed a peptide dubbed DFTamP1, which they then synthesized. DFTamP1 rapidly destroyed MRSA in culture. The group has also used its method to identify another molecule, temporin-PTa8L, that also shows potent antimicrobial activity. The group plans to use these two peptides as templates for another round of computer-based peptide engineering. The researchers may also incorporate the filtering technology directly into their database.