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Updated: Aug 12, 2026
06:55
A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.
Published on: November 7, 2018
Evolutionary genomics of Salmonella: gene acquisitions revealed by microarray analysis
Steffen Porwollik1, Rita Mei-Yi Wong, Michael McClelland
1Sidney Kimmel Cancer Center, 10835 Altman Row, San Diego, CA 92121, USA.
Summary
This study mapped Salmonella Typhimurium LT2 gene homologues across Salmonella species using microarrays. It revealed significant gene gain and loss, with many genes acquired by the ancestor of all Salmonella and subspecies 1.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Salmonella enterica subspecies cause significant infections in mammals and birds.
- Understanding gene content variation is crucial for Salmonella pathogenesis and evolution.
Purpose of the Study:
- To assess the presence of Salmonella enterica sv. Typhimurium LT2 gene homologues in other Salmonella species.
- To infer patterns of gene gain and loss across Salmonella lineages.
Main Methods:
- Hybridization of 22 Salmonella genomes to a microarray containing over 97% of Salmonella Typhimurium LT2 annotated ORFs.
- Phylogenetic analysis based on homologue content to construct evolutionary relationships.
Main Results:
- A phylogenetic tree based on homologue content largely agreed with previous sequence-based studies.
- Predicted gene acquisition events include 513 for the Salmonella ancestor, 111 for S. enterica, 105 for diphasic Salmonella, and 216 for subspecies 1.
- High levels of gene gain, loss, or rapid divergence were observed, with at least 425 potential lateral gene transfers within Salmonella.
Conclusions:
- Gene content evolution in Salmonella is dynamic, characterized by substantial gene gain and loss.
- Genes acquired by subspecies 1 are of particular interest due to their association with mammalian and avian infections.
- Further research into these genes could elucidate Salmonella pathogenesis mechanisms.
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