Extracellular matrix proteo-glycans involved in diatom adhesion and motility

Gretz, M.R.

Journal of Phycology 36(3 Suppl): 26


ISSN/ISBN: 0022-3646
DOI: 10.1046/j.1529-8817.1999.00001-77.x
Accession: 034913673

Download citation:  

Article/Abstract emailed within 0-6 h
Payments are secure & encrypted
Powered by Stripe
Powered by PayPal

Although diatom extracellular matricies are usually thought of exclusively in terms of the beautiful, architecturally complex silicious frustule, polymers exuded through the frustule are critical mediators of interactions with the external environment. In several species, complex proteoglycans appear to be the primary components involved in adhesion and motility. When viewed with high-resolution cryo-scanning electron microscopy methods, the ubiquity and pervasiveness of these polymers was revealed in both freshwater and marine taxa. Monoclonal antibody mapping of carbohydrate epitopes characterized by NMR, methylation and monosaccharide analysis and correlated with structural observations by Em revealed an organizational pattern far more complex than previously proposed. Modeling assembly of extracellular "stalks" in the marine biofouling diatom Achnanthes longipes involves intracellular sequestering of multiple components, deposition at the protoplasmic membrane/diatotepum interface, transport through the multilayered diatotepum and holes in the silica, extrusion from the frustule, and assembly into a very complex multi-laminate biocomposite structure. The mechanism of extracellular polymer participation in motility is complex in a different way, as some current models of raphe associated motility involve cytoskeletal interactions and molecular motors.