The current COVID-19 pandemic maybe waning due to medical and practical interventions; however, we may be entering another major global medical health issue posed by the rise of antibiotic resistant bacteria, which will require targeting multiple pathogens, not just one. This will require the development of several novel antimicrobial materials to tackle this looming global health threat. Here, we show that a new class of antimicrobial agents, termed ‘Structurally Nanoengineered Antimicrobial Polypeptide Particles’ (SNAPPs), synthesized using ring-opening polymerization (ROP) of α-amino acid N-carboxyanhydrides (NCAs) to produce star-shaped polypeptide nanoparticles exhibit potent antibacterial activity. By altering the star-polymer arm composition by end-capping the polymer arms with fatty acids we were able to investigate the effect of adding different alkyl chains (C4-C18) on antimicrobial activity and their cytotoxicity. We show that the Fatty-Acid-SNAPPs (FA-SNAPPs) have enhanced activity compared to the original parent SNAPP using tradition antimicrobial assays determine MIC and MBC as well as showing via microbial flow cytometry that the FA-SNAPPs disrupt the inner/cytoplasmic membrane of bacterial. This membrane disruption capacity was further investigated using microbial flow cytometry assays we have developed to monitor bacterial stress via reactive oxygen species generation and how membrane potential is affected. Cytotoxicity towards mammalian cells was determined by the LDH and MTS bioassays indicating cell death and cell growth inhibition, respectively. Our findings show that short chain fatty acids enhance antimicrobial activity of the SNAPPs while retaining very low cytotoxicity as compared to the parent SNAPP. Taken together, our study demonstrates that inclusion of fatty acids enhances SNAPP antimicrobial efficacy and their ability to target bacteria.