Craspedostauros australis frustule associated components analysis

The biomolecular composition of diatom underwater adhesives remains unknown as does the precise mechanism by which the secretion of adhesive material from the raphe slit is coupled to an intracellular motor that provides the force for cell motility. In this study we have characterized the previously identified frustule associated components (FACs) from the common fouling diatom Craspedostauors australis and demonstrated that they form a continuous cell wall coating. The FACs are encoded by a single polypeptide (caFAP1) that has a domain structure of alternating cysteine-rich and PTS-rich regions which is reminiscent of the gel-forming mucins. CaFAP1 is notably absent from the raphe slit and therefore does not play a direct role in cell adhesion and motility but may rather play an important role in lubrication and self-cleaning that is required for epipsammic benthic diatoms that grow attached to sand grains, or moving through sand.