Detecting HGT: discordant phylogenies OEB 192 – 11.09.21.

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KEY CONCEPT New species can arise when populations are isolated.

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Presentation transcript:

Detecting HGT: discordant phylogenies OEB 192 –

Can gene histories be retraced? (Xie et al., 2004)

1. Found all mobile genetic elements (Lee, Robinson & Marx, in prep) Because this was unpublished, I’m leaving in the part that is not a problem to share and taking out a couple slides later…

(Lee, Robinson & Marx, in prep)

Limitations to HGT

‘Core’ vs. ‘non-core’ genome (Pál et al., 2005)

Limitations to HGT (Fraser et al., 2007) Bacillus subtilis Bacillus mojavensis Streptococcus pneumoniae E. coli

Patterns in HGT of IS elements?

Bacterial immunity against phage/selfish DNA: CRISPRs (Barrangou et al., 2007) (Marraffini and Sontheimer, 2010)

Species “Species are groups of actually or potentially interbreeding populations, which are reproductively isolated from other such groups” (Mayr, 1942)

Monday (9/26): Microbial species & biogeography