Genus XXIII. Gelidibacter

The genus Gelidibacter is a member of the family Flavobacteriaceae. The first strains of the genus to be isolated were from several Antarctic marine samples and the genus is most closely related to other Antarctic genera, including Subsaxibacter and Subsaximicrobium (Bowman and Nichols, 2005). The genus contains four species: Gelidibacter algens, Gelidibacter gilvus, Gelidibacter mesophilus, and Gelidibacter salicanalis.

Gelidibacter species typically form pale to bright yellow colonies with a mucoid consistency and with a spreading margin. The species are all active gliders. Gliding motility is best seen on nutrient-poor media or media containing utilizable carbohydrates. Cells appear usually as rods of highly variant lengths from coccobacilli to filamentous cells up to 15-20 μm long. In ~Ider cultures, cells may degenerate into spheroplast-like bod~es approximately 1-2 μm in diameter. This feature is PartiCUlarly obvious in some strains of Gelidibacter algens.