Local peptidoglycan composition defines division site selection in Streptococcus pneumoniae Nature Microbiology, Published online: 07 April 2026; doi:10.1038/s41564-026-02322-6Sequential peptidoglycan carboxylase activity of DacA and DacB generates a local peptidoglycan signature that recruits MapZ and establishes the division site at the Streptococcus pneumoniae cell equator.

Out Now! Local peptidoglycan composition defines division site selection in Streptococcus pneumoniae #MicroSky

Exciting research here on the development and lab evaluation of #CRISPR #POC tests for #STIs (chlamydia, gonorrhea, syphilis, HSV 1 /2)

Also very interesting they could detect S91F to predict cipro resistance in #gonorrhea

POC tests for STIs can be game-changers in many settings

#STIsky #IDsky

Dr. Cole's presentations at the Neisseria meetings were delightful. So sorry he is gone.

This is a great @cidjournal.bsky.social supplement for all you #gonorrhea, #STI, and #AMR enthusiasts. Or for anyone who’s heard about drug-resistant gonorrhea and wants to learn more.

Will link articles in 🧵 below - check it out and share! #openaccess

#IDsky #STIsky

bsky.app/profile/carb...

A small dish containing black-eyed peas, collard greens, a wedge of cornbread, and a Serrano pepper.

Wishing a happy and successful year to all of you

We mapped the whole human fallopian tube in 3D and at single-cell resolution via our CODA workflow.

More about this work here: biorxiv.org/content/10.1...

Molecular dissection of Class A PBP function uncovers novel features of the non-canonical Clostridioides difficile divisome complex Author summary Bacterial cell division is an ancient and essential process, but our molecular understanding of this process is primarily based on studies in a select few model systems. Recent work fou...

Excited to share my latest postdoctoral work in the Shen Lab at Tufts! In this study, we follow up on an exciting finding by former grad student @shailab.bsky.social that C diff uses its Class A PBP (PBP1) to drive cell division (unlike previously studied bacteria)! journals.plos.org/plosgenetics...

Go Fuzzy Bees!

A Lyt at the end of the tunnel? Unraveling the complex interactions of the N-acetylglucosaminidase LytG in cell wall metabolism The growth and division of the Gram-positive cell requires the coordinated action of enzymes involved in the synthesis and degradation of the heteropolymer peptidoglycan. Herein, we present the use of...

A Lyt at the end of the tunnel? Unraveling the complex interactions of the N-acetylglucosaminidase LytG in cell wall metabolism

RSC Chemical Biology

pubs.rsc.org/en/content/a...

STD Cases Fall, but Not Syphilis in Newborns Overall decreases may be due to a general decline in young people having new partners

STD cases have fallen, but not syphilis in newborns. Data for 2024 from the CDC showed a 3rd consecutive year of fewer gonorrhea cases & the 2nd year of fewer adult cases of chlamydia & the most infectious form of syphilis. However, congenital syphilis cases aren't seeing the same improvements👇

LytF contributes to pilus extrusion during natural competence in Streptococcus sanguinis SK36. Streptococci may enter a physiological state called competence, during which they express a specific set of genes required for exogenous DNA uptake and its subsequent integration into the genome throu...

Cool work by @mkjos.bsky.social Daniel Straume showing that the competence-induced peptidoglycan hydrolase LytF promotes pilus extrusion, thereby enhancing the efficiency of DNA uptake in S, sanguinis. Is this also a major function of the pneumococcal CbpD fratricide?
www.biorxiv.org/content/10.1...

Divisome dynamics in intracellular UPEC cells during infection. Left: Representative confocal image of intracellular UTI89 expressing a division marker (FtsZ-mCitrine; pseudo coloured green) with mCherry (pseudo coloured magenta) as cytoplasmic marker, bladder cell membranes shown in blue (CellBrite Steady Membrane 405) and nuclei shown in gold (NucSpot Live Cell 650). Right: Still images of a time-lapse sequence showing FtsZ-mCitrine (pseudo coloured green) driven coccobacilli divisions imaged using HiLo illumination.

Uropathogenic #Ecoli #UPEC proliferate as round coccoid cells during intracellular infection; @alaskapokhrel.bsky.social @bill-lab.bsky.social &co show that accelerated division via FtsZ constriction drives this, the coccobacillus form persisting for generations @plosbiology.org 🧪 plos.io/4gdx97i

Genetic transformation of Gardnerella species and characterization of vaginolysin and sialidase mutants | Infection and Immunity Genetic manipulation is a fundamental process in the study of bacterial pathogenesis. The ability to make mutations and complements is necessary for definitive identification of virulence genes, and the ability to make unmarked mutations is preferable in these studies (1). Certain bacterial pathogens were considered genetically intractable for many years, such as Mycobacterium tuberculosis or Chlamydia trachomatis, and studies of their virulence mechanisms necessarily focused on epidemiology, immunology, cell biology in the host, and proteomic or transcriptomic analyses (2, 3). Those classic cases were eventually resolved by the discovery of effective transduction, natural transformation, and chemical transformation methods, greatly facilitating the identification of virulence factors (4–7). Gardnerella species have similarly been considered genetically intractable, and like M. tuberculosis and C. trachomatis, Gardnerella have an unusual cell envelope. Similar to other Actinobacteria, Gardnerella are generally considered gram-positive, but stain gram-variable because of their unusual and incompletely characterized envelope (8).

Our paper describing transformation of Gardnerella species is published in Infection and Immunity. We think this will lead to further molecular studies of bacterial vaginosis and potential therapeutics.
journals.asm.org/doi/10.1128/...

Archaea produce peptidoglycan hydrolases that kill bacteria Archaea regularly interact with bacteria but reports of archaea killing bacteria are very rare. This study shows that many archaea encode peptidoglycan hydrolases, which specifically target bacterial ...

This first-author publication is my… first! Archaea kill bacteria by targeting their Achilles’ heel: peptidoglycan. Big shoutout to @ahocher.bsky.social‬, @valeriesoo.bsky.social‬, Pauline Misson, @tobiaswarnecke.bsky.social‬ and MRC LMS Proteomics. A thread 🔽
journals.plos.org/plosbiology/...

Bacterial cell wall & periplasm paradigm shift - important read #MicroSky

www.nature.com/articles/s41...

Thrilled to share the first preprint from my group! Prevotella are predominant but understudied members of the respiratory microbiome. They have a reputation for being hard to work with, but understanding them is likely important for understanding how they contribute to respiratory health. 🧫🔬

Interferon-epsilon, an estrogen-induced type I interferon, is uniquely exploited by Neisseria gonorrhoeae via effects on sialic acid metabolism Kurt-Jones et al. examined IFN-ε, a hormone-responsive type I IFN expressed by genital epithelial cells, during Neisseria gonorrhoeae (Ng) infection. They demonstrated that mice lacking IFN-ε exhibit ...

Kurt-Jones et al. show that IFN-epsilon increases production of CMP-sialic acid from epithelial cells, allowing gonococci to add sialic acid to their lipooligosaccharide and become resistant to an antimicrobial peptide. www.cell.com/cell-host-mi...

Type I interferons give gonococci a sweet treat and a chance at survival In this issue, Kurt-Jones et al. demonstrate a surprising role for the type I interferon, IFN-ε, in Neisseria gonorrhoeae infections of the female reproductive tract. Rather than protecting the host, ...

I wrote a preview for Cell Host & Microbe about the article from Kurt-Jones et al. on IFN-epsilon enhancement of gonococcal infection. One cool facet of this work is that it provides a possible mechanism for Chlamydia to increase gonococcal co-infection. www.cell.com/cell-host-mi...

Cyclic-di-AMP modulates cellular turgor in response to defects in bacterial cell wall synthesis - Nature Microbiology Brogan et al. uncover a signalling pathway in which levels of the nucleotide second messenger c-di-AMP increase in response to defects in cell wall synthesis. This regulatory pathway decreases turgor ...

Very happy to share that a large part of my thesis work is out today: B. subtilis uses the second messenger c-di-AMP to modulate its turgor pressure in response to the state of its cell envelope. www.nature.com/articles/s41...

That headline is a little misleading. The vaccine is the meningococcal vaccine 4CMenB. It's been licensed in the US for ten years, for protecting against group B meningococcal disease. Yes, it provides some protection against gonorrhea, but it's not a new GC vaccine, something that is still needed.

78 morel mushrooms, mostly of the yellow variety, dry on a metal dish rack.

It's the height of morel season in south-central Wisconsin.

Being geneticists, we also needed to complement. We built a complementation construct that directs introduced DNA to a region on the chromosome that is conserved among Gardnerella species. I think these tools should be useful for the whole Gardnerella community.

Finally, Amy made a plasmid that had mutated pheS as a counter-selectable marker. So, we were able to deliver mutation constructs to the chromosome by selecting for the plasmid to integrate and then selecting for it to resolve. The isolates could be screened to see if they kept the mutation.

To get DNA constructs across the actinobacterial envelope, we grew the bacteria with a cell wall-weakening agent, D-cycloserine. To protect the DNA, we needed to methylate it, and circular DNA worked better than linear. So, suicide plasmids worked.

The oligo work was nice, but we wanted to use selectable markers to knock-out virulence and colonization genes. Amy Klimowicz tried many different methods to make electroporation work better, to protect the DNA from degradation, and then to get insertions in the chromosome.

I heard that Dr. Kim Jefferson's lab at VCU was doing oligo recombineering in Gardnerella, and she was nice enough to collaborate with us. Then Dr. Erin Garcia who was doing that work, came to post-doc with us. Erin taught us to electroporate Gardnerella with oligos.

We've worked on Neisseria gonorrhoeae for decades. After an interesting session at the Neisseria meeting in Asilomar, I decided we needed to understand more about the other bacteria that gonococci interact with. Gardnerella was an obvious choice, since BV patients are more likely to get gonorrhea.

Genetic transformation of Gardnerella species and characterization of vaginolysin and sialidase mutants Bacterial vaginosis (BV) is the most prevalent vaginal disorder in women of childbearing age and causes pregnancy complications including preterm birth. Species of Gardnerella increase just prior to t...

Checkout out our preprint describing mutagenesis methods for Gardnerellla species. We showed that a vaginolysin mutant was defective in lysing cervical cells in human cervix explants and that a sialidase mutant was deficient in degrading human cervical mucus.
www.biorxiv.org/content/10.1...

A scanning electron micrograph showing rod-shaped Gardnerella vaginalis bacteria colored purple interacting with coccal Neisseria gonorrhoeae bacteria colored pink, all surrounded by biofilm goo colored yellow. The experiment in the picture was done by Amy Klimowicz, and the false-coloring by Melanie Callaghan.

We have developed methods for making targeted mutations in Gardnerella species. It's been a long slog, and the bacteria put up a lot of hurdles. Thanks to the hard work and ingenuity of Amy Klimowicz and Erin Garcia, we can make deletions, point mutations, and complements. Preprint is on bioRxiv.

Our review on Z-ring placement mechanisms in cocci is out! This was a fun one to write!
#Microsky 🦠🧫