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bioRxiv · 10.1101/2022.11.02.514973

CauloKO: an ordered transposon mutant library in Caulobacter crescentus

Moore, G. M.·Ramos, J. G.·Bratton, B. P.·Gitai, Z.
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Abstract

Genetic screens are powerful approaches to unveiling new biological insight and ordered redundant transposon libraries have emerged as a primary tool for performing screens of known genetic saturation. Newer sequencing methods based on combinatorial pooling have lowered the cost and time required to generate these libraries. Caulobacter crescentus is a gramnegative bacterium that has served as a model for understanding bacterial physiology with a myriad of genetic tools. To add to this collection of tools, we created CauloKO - the first ordered, transposon library in C. crescentus. CauloKO includes insertion mutants in 86% of all non-essential genes and 77% of all open reading frames of strain CB15. CauloKO insertion mutants were validated using Sanger sequencing. We also present phenotypic analysis of the CauloKO library using a crystal violet screen for biofilm mutants, which both confirmed previous results and identified new mutants for future studies. This combined approach revealed that the CauloKO library shows promise for screening applications, particularly for phenotypes that require monoclonal populations of cells.

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Moore, G. M., Ramos, J. G., Bratton, B. P., Gitai, Z.. 2022-11-03. CauloKO: an ordered transposon mutant library in Caulobacter crescentus. https://doi.org/10.1101/2022.11.02.514973

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