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Sarah J Tucker

@sjtucker.bsky.social

190 followers 280 following 31 posts

Microbial ecology & evolution 🦠👩🏻‍🔬 interested in genomic, metabolic, and physiological diversity and their impacts on aquatic systems 🌊🏝️🐠 Keen on oligotrophs 💫 Post-doc @ MBL 🦀 Previous Knauss Fellow in Arctic Ocean Observing ❄️ https://sarahjtucker.com/

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Sarah J Tucker @sjtucker.bsky.social · 15d

I'm delighted our paper is out: doi.org/10.1093/isme...
With new SAR11 isolate genomes and time-series metagenomes, we reveal coastal and offshore SAR11 ecotypes, identify associated metabolic traits, and pinpoint selective gene sweeps as a likely evolutionary driver to niche partitioning. 🌊🦠

Habitat-specificity in SAR11 is associated with a few genes under high selection

Abstract. The order Pelagibacterales (SAR11) is the most abundant group of heterotrophic bacteria in the global surface ocean, where individual sublineages

doi.org

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Reposted by Sarah J Tucker

Amy D Willis @amydwillis.bsky.social · 13h

Are you looking for a #tenuretrack or #openrank job in #biostatistics or #statistics? @fredhutch.org is hiring! Seattle is a wonderful place to grow your career; the bio/stat & science scene here is world-class; and you will work w/ amazing UW Biostat students. Apply!
apply.interfolio.com/176402

Apply - Interfolio {{$ctrl.$state.data.pageTitle}} - Apply - Interfolio

apply.interfolio.com

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Sarah J Tucker @sjtucker.bsky.social · 13d

Thank you, thats so nice to hear :)

Sarah J Tucker @sjtucker.bsky.social · 14d

I also want to mention that the new Fig S6 and a few others in the revised supplementary materials were recommendations from our reviewers. We had some great feedback in review. Hopefully the SM will be live on the ISME site soon

Sarah J Tucker @sjtucker.bsky.social · 14d

Thank you @ilnamkang.bsky.social! The carbon figure is Fig. S6 in the revised manuscript. Strange, it looks like ISME doesn't have the Supplementary Materials up yet. I can send you a copy by email

Sarah J Tucker @sjtucker.bsky.social · 14d

:) Thank you @bjesseshapiro.bsky.social!

Sarah J Tucker @sjtucker.bsky.social · 15d

I am very thankful to the co-authors on this paper and on @kc-freel.bsky.social's paper, including @merenbey.bsky.social, Mike Rappé, Steve Giovannoni, @theotherdrfreel.bsky.social, and Uli Stingl.

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Sarah J Tucker @sjtucker.bsky.social · 15d

This study relied on new SAR11 isolate genomes and taxonomy put forth by Kelle Freel. Together, our studies span different taxonomic and spatial scales to provide complementary evidence that SAR11 diversity segregates into ecologically and genetically cohesive units. doi.org/10.1101/2024...

New isolate genomes and global marine metagenomes resolve ecologically relevant units of SAR11

The bacterial order Pelagibacterales (SAR11) is among the most abundant and widely distributed microbial lineages across the global surface ocean, where it forms an integral component of the marine ca...

doi.org

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Sarah J Tucker @sjtucker.bsky.social · 15d

Our study reveals a polyphyletic distribution of coastal ocean & offshore habitat specialists, where the key genetic features that underlie these habitat preferences appear to have emerged via gene-specific sweeps. 🧹

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Sarah J Tucker @sjtucker.bsky.social · 15d

We then examined the selective pressures on the metabolic traits that associate to distinct coastal or offshore lifestyles of SAR11. We found that they generally experienced high purifying selection, and thus are likely critical to fitness in these distinct environments.

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Sarah J Tucker @sjtucker.bsky.social · 15d

We also observed distinct patterns of molybdenum-dependent enzyme utilization, where some offshore genera have completely lost the capacity to synthesize molybdenum enzymes and other offshore genera have increased reliance on molybdenum enzymes through molybdenum-dependent purine catabolism.

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Sarah J Tucker @sjtucker.bsky.social · 15d

Coastal & offshore genera specialized on different carbon sources. Offshore genera uniquely shared metabolisms that did not rely on glycolysis, while coastal genera uniquely shared metabolisms that did. This hints at fine-scale niche partitioning along the sugar-acid spectrum within SAR11.

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Sarah J Tucker @sjtucker.bsky.social · 15d

We next examined the SAR11 pangenome (focused on former subclades Ia & Ib) to identify metabolic traits associated with coastal and offshore lifestyles. We found subtle metabolic differences between genera, largely limited to a handful of genes involved in organic carbon and nitrogen metabolisms.

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Sarah J Tucker @sjtucker.bsky.social · 15d

We find SAR11 genera partition across coastal and offshore waters of the tropical Pacific. The coastal genera appear in polyphyletic clades suggesting that coastal SAR11 evolved multiple times. Also we find that the habitat preferences of these genera are mostly retained across the global ocean.

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Sarah J Tucker @sjtucker.bsky.social · 15d

Habitat-specificity in SAR11 is associated with a few genes under high selection

Abstract. The order Pelagibacterales (SAR11) is the most abundant group of heterotrophic bacteria in the global surface ocean, where individual sublineages

doi.org

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Reposted by Sarah J Tucker

Michael Manhart @michaelmanhart.bsky.social · Sep 2

I am recruiting a Ph.D. student in microbial ecology, evolution, and systems biology for fall 2026. Please share!
Details: qevomicrolab.org/Documents/Gr...
Apply by October 1 here: forms.gle/38pPS1Ky84HB...

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Reposted by Sarah J Tucker

Eduardo Rocha @epcrocha.bsky.social · Aug 27

Very happy to see this one out: doi.org/10.1093/molbev/msaf192
Here, we assessed the contribution of natural transformation to the acquisition of novel genes. See preprint thread. @molbioevol.bsky.social #microsky #evobio

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Sarah J Tucker @sjtucker.bsky.social · Aug 29

So much said in one (not so little) word 😆🙏

Aidan Wright @aidangcw.bsky.social · Aug 28

We have a winner! Verschlimmbessern - the German word for making things worse by trying to make them better.

It is a compound verb formed from two words: verschlimmern ("to make worse") and verbessern ("to improve")

The corresponding noun is die Verschlimmbesserung.

a man in a sweater says thank you so much for this in yellow letters

ALT: a man in a sweater says thank you so much for this in yellow letters

media.tenor.com

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Sarah J Tucker @sjtucker.bsky.social · Aug 25

microbes on the brain, all day, everyday :)

Sarah J Tucker @sjtucker.bsky.social · Aug 25

Anyone else read 50 μm on this traffic sign? 🔬 #microsky

Traffic sign for merging in 50 meters with a Greek μ for meters, followed by an English m for meters, resulting in 50 μ m.

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Reposted by Sarah J Tucker

Santa Fe Institute @sfiscience.bsky.social · Jul 28

Applications are open for SFI's 2026 Complexity Postdoctoral Fellowships

If you’ve recently earned a Ph.D. in any scientific field and want to pursue independent, transdisciplinary research, consider applying.

Deadline: October 1, 2025
Apply here: santafe.edu/sfifellowship

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Reposted by Sarah J Tucker

Center for Chemical Currencies of a Microbial Planet (C-CoMP) @microbialplanet.bsky.social · Jul 24

📣 New C-CoMP Pub. Alert!
Interested in marine microbial metabolites 🌊🦠? If so, check out this new pub., led by Bryndan Durham & Winn Johnson, that emerged from C-CoMP's Labile DOM workshop: An ecological framework for microbial metabolites in the ocean ecosystem.
tinyurl.com/54bu2xm7

An ecological framework for microbial metabolites in the ocean ecosystem

The ocean microbe-metabolite network involves thousands of individual metabolites that encompass a breadth of chemical diversity and biological functions. These microbial metabolites mediate biogeoch....

aslopubs.onlinelibrary.wiley.com

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Reposted by Sarah J Tucker

Dr. Carly Kenkel @drcarl.bsky.social · May 15

Its that time again - the list of Ecology/Evolution/Marine Bio Labs recruiting grad students for Fall 2026 is live!
PIs enter your position info here: forms.gle/2XTHBP6CZGEn...
Prospective students (and PIs not recruiting) share the composite list: docs.google.com/spreadsheets...
Please share! 🧪

Ecology/Evolution/Marine Biology labs recruiting for Fall 2026

Please complete this form if you are a PI recruiting graduate students for a Fall 2026 start. If you are NOT recruiting, feel free to share the response sheet with prospective students looking for lab...

forms.gle

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Reposted by Sarah J Tucker

Daan Speth @daanspeth.bsky.social · Jun 16

A short preprint describing the GlobDB is now on arXiv: arxiv.org/abs/2506.11896

If you find the resource useful, please also check globdb.org for info on how to cite the underlying resources and tools.

Daan Speth @daanspeth.bsky.social · Jun 10

I'm happy to announce the latest release of the GlobDB, available at globdb.org.

The GlobDB is a database of "species dereplicated" microbial genomes, and as of release 226 contains twice the number of species-representative genomes (306,260) than the latest GTDB release.

home | GlobDB

globdb.org

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Reposted by Sarah J Tucker

Paul Carini @uncultured.carinilab.com · Jun 26

Is this the mechanism by which excess substrate inhibits growth in oligotrophs?

Very important and cool work by @ahoiching.bsky.social @jcamthrash.bsky.social and others

bioRxiv Microbiology @biorxiv-microbiol.bsky.social · Jun 26

Cell cycle dysregulation of globally important SAR11 bacteria resulting from environmental perturbation https://www.biorxiv.org/content/10.1101/2025.06.25.661606v1

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Reposted by Sarah J Tucker

Rogier Braakman @rogierbraakman.bsky.social · Jun 18

‼️I'm looking for a postdoc‼️ Come join effort in using metagenomes to quantify microbial catabolic potential and carbon substrate availability at the ecosystem level. We seek to understand evolutionary forces shaping the carbon cycle. Part of ccomp-stc.org

careers.peopleclick.com/careerscp/cl...

Postdoctoral Associate

MIT - Postdoctoral Associate - Cambridge MA 02139

careers.peopleclick.com

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