Simultaneous assay of every Salmonella Typhi gene using one million transposon mutants

Gemma C. Langridge, Minh Duy Phan, Daniel J. Turner, Timothy T. Perkins, Leopold Parts, Jana Haase, Ian Charles, Duncan J. Maskell, Sarah E. Peters, Gordon Dougan, John Wain, Julian Parkhill*, A. Keith Turner

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    465 Citations (Scopus)


    Very high-throughput sequencing technologies need to be matched by high-throughput functional studies if we are to make full use of the current explosion in genome sequences. We have generated a very large bacterial mutant pool, consisting of an estimated 1.1 million transposon mutants and we have used genomic DNA from this mutant pool, and Illumina nucleotide sequencing to prime from the transposon and sequence into the adjacent target DNA. With this method, which we have called TraDIS (transposon directed insertion-site sequencing), we have been able to map 370,000 unique transposon insertion sites to the Salmonella enterica serovar Typhi chromosome. The unprecedented density and resolution of mapped insertion sites, an average of one every 13 base pairs, has allowed us to assay simultaneously every gene in the genome for essentiality and generate a genome-wide list of candidate essential genes. In addition, the semiquantitative nature of the assay allowed us to identify genes that are advantageous and those that are disadvantageous for growth under standard laboratory conditions. Comparison of the mutant pool following growth in the presence or absence of ox bile enabled every gene to be assayed for its contribution toward bile tolerance, a trait required of any enteric bacterium and for carriage of S. Typhi in the gall bladder. This screen validated our hypothesis that we can simultaneously assay every gene in the genome to identify niche-specific essential genes.

    Original languageEnglish
    Pages (from-to)2308-2316
    Number of pages9
    JournalGenome Research
    Issue number12
    Publication statusPublished - Dec 2009

    Bibliographical note

    Copyright 2010 Elsevier B.V., All rights reserved.


    Dive into the research topics of 'Simultaneous assay of every Salmonella Typhi gene using one million transposon mutants'. Together they form a unique fingerprint.

    Cite this