Rxivist logo

Rxivist combines preprints from bioRxiv with data from Twitter to help you find the papers being discussed in your field. Currently indexing 67,014 bioRxiv papers from 294,953 authors.

Genomic and gene-expression comparisons among phage-resistant type-IV pilus mutants of Pseudomonas syringae pathovar phaseolicola

By Mark Sistrom, Derek Park, Heath E. O’Brien, Zheng Wang, David S Guttman, Jeffrey P. Townsend, Paul E Turner

Posted 20 Aug 2015
bioRxiv DOI: 10.1101/025106 (published DOI: 10.1371/journal.pone.0144514)

Pseudomonas syringae pv. phaseolicola (Pph) is a significant bacterial pathogen of agricultural crops, and phage φ6 and other members of the dsRNA virus family Cystoviridae undergo lytic (virulent) infection of Pph, using the type IV pilus as the initial site of cellular attachment. Despite the popularity of Pph/phage φ6 as a model system in evolutionary biology, Pph resistance to phage φ6 remains poorly characterized. To investigate differences between phage φ6 resistant Pph strains, we examined genomic and gene expression variation among three bacterial genotypes that differ in the number of type IV pili expressed per cell: ordinary (wild-type), non-piliated, and super-piliated. Genome sequencing of non-piliated and super-piliated Pph identified few mutations that separate these genotypes from wild type Pph – and none present in genes known to be directly involved in type IV pilus expression. Expression analysis revealed that 81.1% of GO terms up-regulated in the non-piliated strain were down-regulated in the super-piliated strain. This differential expression is particularly prevalent in genes associated with respiration — specifically genes in the tricarboxylic acid cycle (TCA) cycle, aerobic respiration, and acetyl-CoA metabolism. The expression patterns of the TCA pathway appear to be generally up and down-regulated, in non-piliated and super-piliated Pph respectively. As pilus retraction is mediated by an ATP motor, loss of retraction ability might lead to a lower energy draw on the bacterial cell, leading to a different energy balance than wild type. The lower metabolic rate of the super-piliated strain is potentially a result of its loss of ability to retract.

Download data

  • Downloaded 273 times
  • Download rankings, all-time:
    • Site-wide: 38,925 out of 67,027
    • In evolutionary biology: 2,889 out of 4,454
  • Year to date:
    • Site-wide: 56,900 out of 67,027
  • Since beginning of last month:
    • Site-wide: 58,154 out of 67,027

Altmetric data


Downloads over time

Distribution of downloads per paper, site-wide


Sign up for the Rxivist weekly newsletter! (Click here for more details.)


News