title: Temperature-induced behavioral switches in a bacterial coral pathogen.
abstract: Evidence to date indicates that elevated seawater temperatures increase the occurrence of coral disease, which is frequently microbial in origin. Microbial behaviors such as motility and chemotaxis are often implicated in coral colonization and infection, yet little is known about the effect of warming temperatures on these behaviors. Here we present data demonstrating that increasing water temperatures induce two behavioral switches in the coral pathogen Vibrio coralliilyticus that considerably augment the bacterium's performance in tracking the chemical signals of its coral host, Pocillopora damicornis. Coupling field-based heat-stress manipulations with laboratory-based observations in microfluidic devices, we recorded the swimming behavior of thousands of individual pathogen cells at different temperatures, associated with current and future climate scenarios. When temperature reached ⩾23 °C, we found that the pathogen's chemotactic ability toward coral mucus increased by >60%, denoting an enhanced capability to track host-derived chemical cues. Raising the temperature further, to 30 °C, increased the pathogen's chemokinetic ability by >57%, denoting an enhanced capability of cells to accelerate in favorable, mucus-rich chemical conditions. This work demonstrates that increasing temperature can have strong, multifarious effects that enhance the motile behaviors and host-seeking efficiency of a marine bacterial pathogen.
authors.affiliation: Division of Science and Environmental Policy, California State University Monterey Bay, Seaside, CA, USA.|Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Garren
authors.affiliation: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.|Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
authors.forename: Kwangmin
authors.initials: K
authors.lastname: Son
authors.affiliation: Plant Functional Biology and Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, Australia.
authors.forename: Jessica
authors.initials: J
authors.lastname: Tout
authors.affiliation: Plant Functional Biology and Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, Australia.
authors.forename: Justin R
authors.initials: JR
authors.lastname: Seymour
authors.affiliation: Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich, Switzerland.
authors.forename: Roman
authors.initials: R
authors.lastname: Stocker
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000737:chemistry / Q000382:microbiology*; D002633:Chemotaxis; D057894:Coral Reefs; D054884:Host-Pathogen Interactions; D012623:Seawater / Q000382:microbiology*; D013696:Temperature; D014733:Vibrio / Q000502:physiology*