Machine-Learning-Optimized Peptide CIT8 Clears Carbapenem-Resistant Acinetobacter in 15 Minutes in Lab Tests
Researchers at Houston Methodist Hospital and the National and Kapodistrian University of Athens reported in Frontiers in Microbiology on October 19, 2026 that CIT8, a 13-amino-acid antimicrobial peptide previously tuned by machine learning against MRSA, also kills drug-resistant Gram-negative bacteria. It inhibited 15 of 16 Acinetobacter baumannii strains at 4 µg/mL, including carbapenem-resistant clinical isolates, and at five times that dose cut about 50 million bacteria per mL to undetectable levels within 15 minutes by breaking their membranes. CIT8 and a mirror-image version also disrupted biofilms with relatively low toxicity to human cells; the work is in the lab.