Mikrobiota hos grønn kråkebolle, Strongylocentrotus droebachiensis. Fokus på identifikasjon av bakteriestammer

Abstract

It has been reported that the green sea urchin, Strongylocentrotus droebachiensis, can be affected by symptoms that is associated with the disease called “bald sea urchin disease”. However, no pathogen for sea urchins are known in the literature, but a working hypothesis claims that species of the Vibrio splendidus clade can be associated with symptoms characterized as bald sea urchin disease in S. droebachiensis.

With use of 16S rRNA sequencing, it is shown in this study that species belonging to the V. splendidus clade are present in both healthy and diseased S. droebachiensis. As gene sequencing proved to be a time consuming, costly and unreliable method for identifying Vibrio bacteria at species level, a MALDI-TOF MS database was developed for easier and faster identification of certain Vibrio species. In addition, further analysis was performed with whole genome sequencing on some of the V. splendidus related isolates from diseased S. droebachiensis. Virulence factors such as OmpU, vsm, flagellum and hemolytic activity were found in the isolates, but still a small challenge experiment could not verify the working hypothesis.