Audrey Proença

On my way and looking forward to it!

I'll have a look at your paper to have a better sense for it, but for now the presence of casamino acids seems to be the main difference. We have tried different glucose concentrations before, so I don't think 0.4 vs 0.2% gluc explains it.
If you try adding casamino acids, let me know how it goes!

Ohh that's interesting!
We can add Sampaio et al. 2022 to the list of labs who have seen the fluctuation (doi.org/10.1073/pnas.2115032119).
They also used M9 + 0.4% glucose + 0.2% casamino acids.

Progressive decline in old pole gene expression signal enhances phenotypic heterogeneity in bacteria Bacterial aging increases variance in gene expression and protein inheritance through a gradual decline in old pole activity.

Excited to share our latest paper, where we show the development of gene expression asymmetry in aging E. coli!
Work done in the Evolutionary Demography Group at FU Berlin with @mtugrul.bsky.social, @arpitanath.bsky.social and Ulrich Steiner.

www.science.org/doi/10.1126/...

Thanks #MEEhubs2024 for the opportunity to present my work online, despite the visa delays that prevented me from joining in Lausanne. It was great to interact with the hubs this morning! @meehubs.bsky.social

Thanks for the interest! In the end, aging makes bacteria different from each other. Having these differences can help them survive difficult situations: some stresses can kill the mother cell, while the daughter still survives (and vice-versa). What matters is that someone survives!

The difference between bacteria and stem cells is how asymmetric the division can be. E. coli divide their damage with some asymmetry, but it's more like a 60-40 split between mother and daughter. If they're under stress, it can still mean that the mother dies and the daughter survives :)

I love the stem cell analogy! Every time a bacterium divides, the cell inheriting a new pole (the one that was created from the fission site) is what we call the daughter. Damage tends to get stuck in the pole over time, so getting a freshly made pole is a good thing.

It's not hard, but it requires time-lapse to know which cell inherits the new pole from the previous generation. It can be done with WT cells, without fluorescent markers.
It's a lot harder without following lineages over time, but some polar markers can tell which is more likely to be a daughter.

Excited to join this conference from Berlin! Our Evolutionary Demography Lab is looking forward to all talks & posters, and the exchange of ideas to come over the next few days!

Graphical representation of aging bacterial lineages, with a mother cell that retains damage and produces rejuvenated daughters.

Hello Bluesky! I'm Audrey, an evolutionary microbiologist exploring aging with an unconventional choice of model organism: bacteria! I track cell lineages as they grow and divide to investigate the most basic principles of aging, like the accumulation and partitioning of cellular damage.

#evosky