Jan-Willem Veening
@veeninglab.com
Professor and director at the Department of Fundamental Microbiology, University of Lausanne, https://veeninglab.com/. Interested in antibiotic resistance, bacterial cell biology, host-microbe interactions.
It will be interesting to test whether induction of RipA leads to stalled replication and subsequent increased comCDE copy numbers and that this is the mechanism for triggered competence. Seems like a simple experiment but they don't like this hypothesis for some reason 🤷♂️
September 3, 2025 at 7:01 AM
It will be interesting to test whether induction of RipA leads to stalled replication and subsequent increased comCDE copy numbers and that this is the mechanism for triggered competence. Seems like a simple experiment but they don't like this hypothesis for some reason 🤷♂️
Tour de force paper by Jingren Zhang's group @tsinghuauniversity.bsky.social showing a complex link between peptidoglycan acetylation and phase variation through nutrient sensing #MicroSky journals.plos.org/plospathogen...
August 8, 2025 at 11:11 AM
Tour de force paper by Jingren Zhang's group @tsinghuauniversity.bsky.social showing a complex link between peptidoglycan acetylation and phase variation through nutrient sensing #MicroSky journals.plos.org/plospathogen...
Of course, we ( @axeljanssen.bsky.social) setup a genome browser with a track with sgRNA target sites for easy target validation and gene hunting
August 7, 2025 at 4:33 PM
Of course, we ( @axeljanssen.bsky.social) setup a genome browser with a track with sgRNA target sites for easy target validation and gene hunting
Great collaboration with the lab of Junkal Garmendia, spearheaded by Celia and Johann. First we setup CRISPRi for this bacterium and then generated a genome-wide sgRNA library that allows us to do CRISPRi-seq.
August 7, 2025 at 4:33 PM
Great collaboration with the lab of Junkal Garmendia, spearheaded by Celia and Johann. First we setup CRISPRi for this bacterium and then generated a genome-wide sgRNA library that allows us to do CRISPRi-seq.
Great review by @pinholab.bsky.social and Simon Foster on the current knowledge regarding growth, elongation and division of Staphylococcus aureus www.annualreviews.org/content/jour...
November 21, 2024 at 5:42 PM
Great review by @pinholab.bsky.social and Simon Foster on the current knowledge regarding growth, elongation and division of Staphylococcus aureus www.annualreviews.org/content/jour...
The work supports a model in which the S protein activates PBP1a at sites of cell wall damage. PgdA then deacetylates the newly synthesized PG making the cell wall once again resistant to antimicrobial attack. In absence of the S protein, the complex remains stuck leading to cell death
November 10, 2024 at 4:35 PM
The work supports a model in which the S protein activates PBP1a at sites of cell wall damage. PgdA then deacetylates the newly synthesized PG making the cell wall once again resistant to antimicrobial attack. In absence of the S protein, the complex remains stuck leading to cell death
S protein mutants are also more sensitive to host-derived antimicrobials such as lysozyme and LL-37 and are attenuated in a zebrafish meningitis and mouse pneumonia infection model.
November 10, 2024 at 4:35 PM
S protein mutants are also more sensitive to host-derived antimicrobials such as lysozyme and LL-37 and are attenuated in a zebrafish meningitis and mouse pneumonia infection model.
In absence of the S protein, a smaller proportion of PBP1a molecules move circumferentially and cells are consequently misshapen and more sensitive to cell wall damage and antibiotics.
November 10, 2024 at 4:35 PM
In absence of the S protein, a smaller proportion of PBP1a molecules move circumferentially and cells are consequently misshapen and more sensitive to cell wall damage and antibiotics.
We show that the pneumococcal S protein regulates the activity of the class A penicillin binding protein PBP1a and is in a complex with the peptidoglycan (PG) modifying enzyme PgdA (and interacts with several other proteins such as GpsB and MpgA). Also nice colocalization with PBP1a and PgdA.
November 10, 2024 at 4:35 PM
We show that the pneumococcal S protein regulates the activity of the class A penicillin binding protein PBP1a and is in a complex with the peptidoglycan (PG) modifying enzyme PgdA (and interacts with several other proteins such as GpsB and MpgA). Also nice colocalization with PBP1a and PgdA.
This project started already in 2014 when Clement GFP tagged all hypothetical proteins in S.pneumoniae and we found that this enigmatic LysM-domain containing protein, now called the S protein, was midcell localized through its TM domain. Its also at mid-cell in Streptococcus salivarius.
November 10, 2024 at 4:35 PM
This project started already in 2014 when Clement GFP tagged all hypothetical proteins in S.pneumoniae and we found that this enigmatic LysM-domain containing protein, now called the S protein, was midcell localized through its TM domain. Its also at mid-cell in Streptococcus salivarius.
Bacitracin/levofloxacin combination therapy was also effective in vivo and improved the treatment of fluoroquinolone-resistant S. pneumoniae infection in a zebrafish meningitis model.
October 31, 2024 at 8:49 AM
Bacitracin/levofloxacin combination therapy was also effective in vivo and improved the treatment of fluoroquinolone-resistant S. pneumoniae infection in a zebrafish meningitis model.
Activating the LiaR-regulon by the cell envelope-targeting antibiotic bacitracin synergized with ciprofloxacin and levofloxacin. This synergistic antibiotic combination restored sensitivity in fluoroquinolone-resistant strains in vitro.
October 31, 2024 at 8:49 AM
Activating the LiaR-regulon by the cell envelope-targeting antibiotic bacitracin synergized with ciprofloxacin and levofloxacin. This synergistic antibiotic combination restored sensitivity in fluoroquinolone-resistant strains in vitro.
This makes LiaS unable to dephosphorylate LiaR. LiaR then activates its regulon. This model makes sense physiologically for a membrane homeostasis sensing system as upon membrane damage the system does not require an intact phosphotransfer reaction, which might be compromised
October 31, 2024 at 8:48 AM
This makes LiaS unable to dephosphorylate LiaR. LiaR then activates its regulon. This model makes sense physiologically for a membrane homeostasis sensing system as upon membrane damage the system does not require an intact phosphotransfer reaction, which might be compromised
Surprisingly, downregulation of liaS caused fluoroquinolone hypersensitivity. LiaS is part of the LiaFSR (VraTSR) three-component regulatory system involved in cell envelope homeostasis. We show that LiaS keeps the response regulator LiaR inactive.
October 31, 2024 at 8:47 AM
Surprisingly, downregulation of liaS caused fluoroquinolone hypersensitivity. LiaS is part of the LiaFSR (VraTSR) three-component regulatory system involved in cell envelope homeostasis. We show that LiaS keeps the response regulator LiaR inactive.
These profiles show a very specific gene essentiality signature shared between 3 different fluoroquinolones; levo-, cipro- and moxifloxacin, something not seen with Tn-seq or RNA-seq approaches. Not surprisingly, genes involved in DNA repair become more essential.
October 31, 2024 at 8:47 AM
These profiles show a very specific gene essentiality signature shared between 3 different fluoroquinolones; levo-, cipro- and moxifloxacin, something not seen with Tn-seq or RNA-seq approaches. Not surprisingly, genes involved in DNA repair become more essential.
Superresolution microscopy (SIM, PALM), ChIP-seq, Hi-C, Streptococcus pneumoniae. What’s not to like?! Many thanks also to (then) MSc students Jasper&Barbara. Project started years ago in Groningen and brilliantly completed by Maria Vittoria
September 28, 2024 at 2:37 PM
Superresolution microscopy (SIM, PALM), ChIP-seq, Hi-C, Streptococcus pneumoniae. What’s not to like?! Many thanks also to (then) MSc students Jasper&Barbara. Project started years ago in Groningen and brilliantly completed by Maria Vittoria
Most genes are not essential in any given bacteria under any given condition. This makes it hard to assign function to genes. Uncovering genetic interactions such as synthetic lethal (negative) GIs is a great way to figure out what a gene does. Here comes dual CRISPRi-seq!
August 17, 2024 at 5:05 AM
Most genes are not essential in any given bacteria under any given condition. This makes it hard to assign function to genes. Uncovering genetic interactions such as synthetic lethal (negative) GIs is a great way to figure out what a gene does. Here comes dual CRISPRi-seq!
Now online at Cell Host & Microbe! From CRISPRi-seq to a new potent pneumococcal vaccine. Great collaboration with the lab of Jean-Claude Sirard, @gruberlab.bsky.social Victor Nizet. Congrats to Xue and Laurye for their amazing work!
authors.elsevier.com/a/1ig8V6t8JE...
authors.elsevier.com/a/1ig8V6t8JE...
February 28, 2024 at 7:15 AM
Now online at Cell Host & Microbe! From CRISPRi-seq to a new potent pneumococcal vaccine. Great collaboration with the lab of Jean-Claude Sirard, @gruberlab.bsky.social Victor Nizet. Congrats to Xue and Laurye for their amazing work!
authors.elsevier.com/a/1ig8V6t8JE...
authors.elsevier.com/a/1ig8V6t8JE...
Reminder to sign up for the 2024 Streptococcal GRS and GRC!
February 10, 2024 at 10:53 AM
Reminder to sign up for the 2024 Streptococcal GRS and GRC!
Congratulations to Julien for his BactExtract paper published and successfully defending his PhD! Many thanks to @pinholab.bsky.social and @gruberlab.bsky.social for the expert discussions!
www.microbiologyresearch.org/content/jour...
www.microbiologyresearch.org/content/jour...
January 28, 2024 at 7:24 AM
Congratulations to Julien for his BactExtract paper published and successfully defending his PhD! Many thanks to @pinholab.bsky.social and @gruberlab.bsky.social for the expert discussions!
www.microbiologyresearch.org/content/jour...
www.microbiologyresearch.org/content/jour...
Very excited to announce the 2024 Streptococcal Biology GRC (11-16 Aug) and GRS (10-11)! Co-organized with Michael Federle, @kimingeneva.bsky.social Jose Lemos, Kristin Huse, Luke Joyce.
Great line up of speakers and discussion leaders!
Registration: www.grc.org/streptococca...
Great line up of speakers and discussion leaders!
Registration: www.grc.org/streptococca...
December 19, 2023 at 4:26 PM
Very excited to announce the 2024 Streptococcal Biology GRC (11-16 Aug) and GRS (10-11)! Co-organized with Michael Federle, @kimingeneva.bsky.social Jose Lemos, Kristin Huse, Luke Joyce.
Great line up of speakers and discussion leaders!
Registration: www.grc.org/streptococca...
Great line up of speakers and discussion leaders!
Registration: www.grc.org/streptococca...
November 16, 2023 at 12:39 PM
Join us on Friday the 8th of December 16:15h at the Biophore for the inaugural lecture of Yolanda Schaerli. We're so happy to have Yolanda as colleague at the DMF and this will be very entertaining with an apéro to finish! Read more here: www.unil.ch/fbm/fr/home/...
November 16, 2023 at 8:39 AM
Join us on Friday the 8th of December 16:15h at the Biophore for the inaugural lecture of Yolanda Schaerli. We're so happy to have Yolanda as colleague at the DMF and this will be very entertaining with an apéro to finish! Read more here: www.unil.ch/fbm/fr/home/...
Nice to catch up with @liselotdewachter.bsky.social and help get her new lab ready and stocked up with our favorite strains 😅💪
November 11, 2023 at 7:41 AM
Nice to catch up with @liselotdewachter.bsky.social and help get her new lab ready and stocked up with our favorite strains 😅💪
Congratulations to Afonso for a great public PhD defence, completely coded in Python! Nice to see Nassos also present ;-)
October 6, 2023 at 3:56 PM
Congratulations to Afonso for a great public PhD defence, completely coded in Python! Nice to see Nassos also present ;-)