Fig. 1

Defining the essential genes in S. islandicus M.16.4. a Schematic overview of the genome-wide transposon mutagenesis strategy. b Evaluation of gene essentiality by two computational programs: ESSENTIALS²³ and Tn-Seq-Explorer²⁴. Points indicate individual genes plotted according to the scores returned by each program. Histograms indicate the number of genes of a particular score, and the dotted lines indicate the recommended cutoffs returned by each program as the local minimum between the essential and non-essential score distributions. Essential genes meet both criteria (lower-left quadrant). The protein-coding genes that only met the ESSENTIALS or Tn-Seq-Explorer criteria were deemed as “unassigned candidates” leaving the rest as likely non-essential to S. islandicus M.16.4 growth under these conditions. A complete list of the log₂FC and EI for the S. islandicus M.16.4 genes from the combined mutant libraries are provided in Supplementary Data 2