Labyrinthula isolate SR_Ha_C growing on seawater-serum agar culture media. The isolate grows in a dense formation, with individual cells packed tightly. The leading edge (in the right of the frame) is where the new ‘colony’ grows. Older parts of the culture exhibiting both in-agar and on-agar growth, giving it a fuzzy look. Photo was taken on an inverted phase contrast microscope. Photo credit: Stacey Trevathan-Tackett, Trevathan-Tackett SM, Sullivan BK, Robinson K, Lilje O, Macreadie PI, Gleason FH. Pathogenic Labyrinthula associated with Australian seagrasses: Considerations for seagrass wasting disease in the southern hemisphere. Microbiol Res. 2018 Jan;206:74-81. doi: 10.1016/j.micres.2017.10.003. Epub 2017 Oct 9. PMID: 29146262.

The Labyrinthula sp. SR_Ha_C genome sequence and gene models have not been determined by the JGI, but were provided by Stacey Trevathan-Tackett at Deakin University. Please note that this copy of the genome is not maintained by Trevathan-Tackett and Tan and is therefore not automatically updated. In order to allow comparative analyses with other algal genomes sequenced by the JGI, a copy of this genome is incorporated into PhycoCosm. The JGI Annotation Pipeline was used to add functional annotation to this genome.

The following text is from Trevathan-Tackett:

Members of the genus Labyrinthula are marine heterotrophic protists, although they’ve historically had various classifications, such as fungi and slime molds. These protists are found ubiquitously around the world and typically need salinities above 15 psu. Ecologically, they degrade organic matter, including algae, mangrove and seagrass plant tissue. However, they are most known for their ability to invade living seagrass leaves, causing cell death and leaf blackening. The black lesions are indicative of Seagrass Wasting Disease (SWD) caused by pathogenic or virulent isolates of Labyrinthula. SWD caused by Labyrinthula has led to major die-backs of seagrass and turfgrass. The Labyrinthula genomes are expected to increase our understanding of the seagrass-Labyrinthula pathosystem, causes of disease outbreaks and Labyrinthula ecology itself. This work will also help build foundational knowledge of this protist’s role in biogeochemical cycling and use as a source of long-chain fatty acids.