Counting Chromosomes in Individual Bacteria to Quantify Their Impacts on Persistence. Author Allison Murawski, Katherine Rittenbach, Christina DeCoste, Gary Laevsky, Mark Brynildsen Publication Year 2021 Type Journal Article Abstract Persisters are phenotypic variants within bacterial populations that tolerate antibiotic treatments considerably better than the majority of cells. A phenotypic quality that varies within bacterial populations is the chromosome number of individual cells. One, two, four, or more chromosomes per cell have been observed previously, and the impact of genome copy number can range from gene dosage effects to an inability to perform specific DNA repair functions, such as homologous recombination. We hypothesize that chromosome abundance is an underappreciated phenotypic variable that could impact persistence to antibiotics. Here, we describe methodologies to segregate bacterial populations based on chromosome number, assess the purity of those subpopulations, and suggest assays that could be used to quantify the impacts of genome abundance on persistence. Keywords Anti-Bacterial Agents, Bacteria, DNA Repair, Homologous Recombination, Chromosomes Journal Methods Mol Biol Volume 2357 Pages 125-146 Date Published 2021 ISSN Number 1940-6029 DOI 10.1007/978-1-0716-1621-5_9 Alternate Journal Methods Mol Biol PMCID 7136161 PMID 34590256 PubMedPubMed CentralGoogle ScholarBibTeXEndNote X3 XML