RT Journal Article SR Electronic T1 Conjugation factors controlling F-plasmid antibiotic resistance transmission JF bioRxiv FD Cold Spring Harbor Laboratory SP 271254 DO 10.1101/271254 A1 Hanna Alalam A1 Fabrice E. Graf A1 Martin Palm A1 Marie Abadikhah A1 Martin Zackrisson A1 Matilda Mattsson A1 Chris Hadjineophytou A1 Linnéa Persson A1 Simon Stenberg A1 Payam Ghiaci A1 Per Sunnerhagen A1 Jonas Warringer A1 Anne Farewell YR 2018 UL http://biorxiv.org/content/early/2018/03/05/271254.abstract AB The rapid horizontal transmission of many antibiotic resistance genes between bacterial host cells on conjugative plasmids is a major cause of the accelerating antibiotic resistance crisis. Preventing understanding and targeting conjugation, there currently are no experimental platforms for fast and cost-efficient screening of genetic effects on antibiotic resistance transmission by conjugation. We introduce a novel experimental framework to screen for conjugation based horizontal transmission of antibiotic resistance between >60.000 pairs of cell populations in parallel. Plasmid-carrying donor strains are constructed in high throughput. We then mix the resistance plasmid carrying donors with recipients in a design where only transconjugants can reproduce, measure growth in dense intervals and extract transmission times as the growth lag. As proof-of-principle, we exhaustively explored chromosomal genes controlling F plasmid donation within E. coli populations, by screening the Keio deletion collection at high replication. We recover all six known chromosomal gene mutants affecting conjugation and identify >50 novel factors, all of which diminish antibiotic resistance transmission. We verify 10 of the novel genes’ effects in a liquid mating assay. The new framework holds great potential for exhaustive disclosing of candidate targets for helper drugs that delay resistance development in patients and societies and improves the longevity of current and future antibiotics.