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Saria McKeithen-Mead, PhD

@sciria.bsky.social

1.1K followers 130 following 14 posts

HHMI Hanna Gray Fellow at Stanford University in KC Huang's Lab | PhD @ MIT Biology in Grossman Lab | Exploring mechanisms driving horizontal gene transfer in the human gut microbiome | 🏳️‍🌈🍸🥘⛺

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Reposted by Saria McKeithen-Mead, PhD

Sarafan ChEM-H @stanford-chemh.bsky.social · 28d

Next Generation Faculty Symposium

SESSION 3: Immunology and Cell-Cell Interactions

More on the speakers: www.berkeleystanfordnextgensymposium.com/speakersalumni

Saria McKeithen-Mead, PhD, is a Postdoctoral Research Fellow at Stanford University (sariam@stanford.edu); Juan Inclan Rico, PhD,
is a Postdoctoral Research Fellow at the University of Pennsylvania (jmirico.k16@gmail.com); Christian Dzuvor, PhD, is a Postdoctoral Research Fellow at Harvard University (christian_dzuvor@hsph.harvard.edu)

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Saria McKeithen-Mead, PhD @sciria.bsky.social · Sep 3

Honored to be selected to speak at this symposium. Please tune in on Sept. 10th if you’re interested in hearing what I’ve learned while mapping HGT in the gut microbiome!

www.berkeleystanfordnextgensymposium.com

Stanford.Berkeley.UCSF Next Generation Faculty Symposium

www.berkeleystanfordnextgensymposium.com

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Reposted by Saria McKeithen-Mead, PhD

George O'Toole (he/him/his) @geiselbiofilm.bsky.social · Feb 28

JB Editor's Choice: McKeithen-Mead, Grossman et al. explore the mechanism whereby ICEBs1, an integrative and conjugative element (ICE) of B. subtilis, inhibits the host SOS response and RecA function.
journals.asm.org/doi/10.1128/...
@asm.org #JBacteriology

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Reposted by Saria McKeithen-Mead, PhD

Anthony Shiver @anthonyshiver.bsky.social · Mar 13

Interested in the influence of the infant microbiome on health? Quickly interrogating non-model organisms using omic approaches?

A new publication, describing genome-scale resources in bifidobacteria, is now available online: doi.org/10.1016/j.ce...

#microbiome #microsky

Silhouettes of infant, mouse, chick, and bacteria.

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Saria McKeithen-Mead, PhD @sciria.bsky.social · Jan 26

doi.org/10.1371/jour...

Timing of integration into the chromosome is critical for the fitness of an integrative and conjugative element and its bacterial host

Author summary Horizontal gene transfer contributes significantly to microbial evolution, enabling bacteria to rapidly acquire new genes and traits. Integrative and conjugative elements (ICEs) are mob...

doi.org

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Saria McKeithen-Mead, PhD @sciria.bsky.social · Jan 26

If you're excited about MGEs and the transference of this type of perspective to the gut microbiome, I hope to update everyone soon on some work I've been doing regarding HGT in the mammalian gut. Here's a snapshot of things to come.

Saria McKeithen-Mead, PhD @sciria.bsky.social · Jan 26

And 2) show that the timing of integration in transconjugants is critically important and links two essential functions of the ICE lifecycle: replication and integration.

Saria McKeithen-Mead, PhD @sciria.bsky.social · Jan 26

In the paper, we delve a bit into why MGEs may have evolved these functions. If interested in more work like this, please check out some of my other publications where 1) we characterize how an integrative and conjugative element finds its integration site:
doi.org/10.1093/nar/...

Target search by an imported conjugative DNA element for a unique integration site along a bacterial chromosome during horizontal gene transfer

Abstract. Integrative and conjugative elements (ICEs) are mobile genetic elements that can transfer by conjugation to recipient cells. Some ICEs integrate

doi.org

Saria McKeithen-Mead, PhD @sciria.bsky.social · Jan 26

Though not fully elucidated here, this seems to differ from the mechanism utilized by PsiB encoded by F-plasmid as it is active in donors and is not believed to interact directly with RecA. Alam Heredia has done excellent follow-up characterizing the mechanism of action here: doi.org/10.1101/2024...

Saria McKeithen-Mead, PhD @sciria.bsky.social · Jan 26

We show that ICEBs1 in Bacillus subtilis encodes genes that inhibit RecA filament formation. This prevents activation of co-resident prophages following a DNA damage event and inhibits ICEBs1-mediated activation of the SOS response during rolling-circle replication.