biostudies-literatureKasteel MDutch Research Council (NWO)e1012577https://www.ebi.ac.uk/biostudies/studies/S-EPMC11554144biostudies-literatureUnknown20(9)Microswimmers are single-celled bodies powered by flagella. Typical examples are zoospores, dispersal agents of oomycete plant pathogens that are used to track down hosts and infect. Being motile, zoospores presumably identify infection sites using chemical cues such as sugars, alcohols and amino acids. With high-speed cameras we traced swimming trajectories of Phytophthora zoospores over time and quantified key trajectory parameters to investigate chemotactic responses. Zoospores adapt their native run-and-tumble swimming patterns in response to the amino acid glutamic acid by increasing the rate at which they turn. Simulations predict that tuneable tumble frequencies are sufficient to explain zoospore aggregation, implying positive klinokinesis. Zoospores thus exploit a retention strategPLoS pathogensPhytophthora zoospores display klinokinetic behaviour in response to a chemoattractant.PMC11554144GSGT. GSGT.2018.024Sprakel JKetelaar TRajamuthu TPGovers FKasteel MfalsePhytophthora zoospores display klinokinetic behaviour in response to a chemoattractant.Microswimmers are single-celled bodies powered by flagella. Typical examples are zoospores, dispersal agents of oomycete plant pathogens that are used to track down hosts and infect. Being motile, zoospores presumably identify infection sites using chemical cues such as sugars, alcohols and amino acids. With high-speed cameras we traced swimming trajectories of Phytophthora zoospores over time and quantified key trajectory parameters to investigate chemotactic responses. Zoospores adapt their native run-and-tumble swimming patterns in response to the amino acid glutamic acid by increasing the rate at which they turn. Simulations predict that tuneable tumble frequencies are sufficient to explain zoospore aggregation, implying positive klinokinesis. Zoospores thus exploit a retention strateg2024-01-01T00:00:00Z2024 Sep2025-04-04T00:10:39.996Z2025-04-04T00:10:39.996ZS-EPMC115541443934840610.1371/journal.ppat.1012577