Time-lapse proteomics unveil constant high exposure of non-antibiotic drug induces synthetic susceptibility towards regular antibiotics.

Antibiotic resistance is a significant threat to the human race, as regular consumption of antibiotics may lead to antibiotic-resistant bacterial strains. Non-antibiotic drugs also have an extensive impact on bacterial strains, where persistent uptake alters the survival mechanisms of bacteria that could lead to cross-resistance towards other antibiotics. Here, we use time-lapse proteomics shift assays to examine Gram-negative (E. coli. O157:H7 and P. aeruginosa) and Gram-positive (E. faecalis and S. aureus) strains of bacteria for short and continuous exposure to the non-antibiotic drug Hydroxychloroquine (HCQ). Proteomic transitions from wild type to HCQ-exposed strains revealed bacterial transitions and their survival adaptabilities, which were different across all strains. In addition to their structural differences, some shared pathways were enriched among Gram-negative and positive strains. We also validated the cross-resistance and sensitivity towards 24 regularly prescribed antibiotics, indicating that long-term exposure to non-antibiotic drugs may induce general proteomics alterations in the bacterial strains, promoting antibiotic resistance. We validated that HCQ exposure renders Gram-negative strains resistant to Β-lactam and susceptible to macrolides and folic acid. In contrast, Gram-positive strains become susceptible to Β-lactam and resistant to aminoglycosides. Exposure to non-antibiotic drugs causes resistance or susceptibility toward other antibiotics, providing clinicians a reason to overcome antibiotic resistance.