Josy ter Beek

Feb 15, 2024 | biorxiv.org | Wei-Sheng W. Sun |Gabriel Torrens |Josy ter Beek |Felipe Cava

AbstractConjugative Type 4 Secretion Systems (T4SS) are a main driver for the spread of antibiotic resistance genes and virulence factors in bacteria. To deliver the DNA substrate to recipient cells, it must cross the cell envelopes of both donor and recipient mating bacteria. In the T4SS from the enterococcal conjugative plasmid pCF10, PrgK is known to be the active cell wall degrading enzyme. It has 3 predicted extracellular hydrolase domains, LytM, SLT and CHAP.

Feb 12, 2024 | nature.com | Laura Alvarez |Gabriel Torrens |Josy ter Beek |Vega Miguel-Ruano |Federico Gago |Ronnie P-A. Berntsson

AbstractThe bacterial cell-wall peptidoglycan is made of glycan strands crosslinked by short peptide stems. Crosslinks are catalyzed by DD-transpeptidases (4,3-crosslinks) and LD-transpeptidases (3,3-crosslinks). However, recent research on non-model species has revealed novel crosslink types, suggesting the existence of uncharacterized enzymes. Here, we identify an LD-transpeptidase, LDTGo, that generates 1,3-crosslinks in the acetic-acid bacterium Gluconobacter oxydans.

Nov 1, 2023 | biorxiv.org | Akbar Espaillat |Laura Alvarez |Gabriel Torrens |Josy ter Beek

AbstractMost bacteria are surrounded by an essential protective mesh-like structure called peptidoglycan, made of glycan chains crosslinked through short peptides by enzymes known as transpeptidases. Of these, penicillin-binding DD-transpeptidases connect adjacent peptide stems between their 4th and 3rd amino acids (4,3-type), D-alanine and a meso-diaminopimelic acid (mDAP) in Gram negatives, whereas LD-transpeptidases make the 3,3-type between mDAP3 residues.

Jun 26, 2023 | nature.com | Josy ter Beek |Laura Alvarez |André Mateus |Remy Colin |Athanasios Typas |Mikhail M. Savitski | +3 more

AbstractTo explore favourable niches while avoiding threats, many bacteria use a chemotaxis navigation system. Despite decades of studies on chemotaxis, most signals and sensory proteins are still unknown. Many bacterial species release d-amino acids to the environment; however, their function remains largely unrecognized. Here we reveal that d-arginine and d-lysine are chemotactic repellent signals for the cholera pathogen Vibrio cholerae.