MEPS 119:229-236 (1995)  -  doi:10.3354/meps119229

Films that form quickly on surfaces immersed in the ocean influence the settlement of microbes and eukaryotic cells via differential distribution of specific receptors that initiate attachment and metamorphosis. This study probed both inert, non-biological surfaces (glass slides) and living surfaces (leaves of seagrass Halophila hawaiiana) with fluorescently labelled lectins to detect and describe distributions of glycoconjugates deployed on surface films. Lectins from Canavalis ensiformis (Con A) and Limulus polyphemus (limulin) bound particular glycoconjugates in films that formed 1 and 3 d following immersion of glass slides in Pearl Harbor (Hawai'i, USA) waters. A complex spatial pattern in film development was observed on glass surfaces; approximately circular areas of reduced receptor densities were interspersed in an otherwise homogeneous matrix. The circular area surrounded centrally located aggregates of particles (including microbes) in 1 d films. The diameter of these zones increased nearly 10-fold when 1 and 3 d films were compared. A third lectin from Helix pomatia localized a third set of glycoconjugates in specific filmed areas and with the organic matter associated with bacteria on 3 d films. Each lectin also bound to surface glycoconjugates on newly emergent leaves of H. hawaiiana with qualitatively different results than those observed for glass. The distributions of receptors for Con A, H. pomatia and limulin lectins were less dense on seagrass surfaces than on filmed glass. Also, receptors for limulin and H. pomatia lectins were associated with the cell walls and peripheral cytoplasm of seagrass cells, not in surface films on leaves. Con A localized glycoconjugates showed only a faint signal on the cell walls of these young leaves. This technique documents previously undescribed spatial and chemical heterogeneities of early, similarly aged surfaces. This understanding allows the definition and localization of possible microscale cues for biofouling. These early steps are expected to be crucial to the distribution of sessile organisms in marine environments.

Lectins . Molecular probes . Biofilms . Epifluorescence microscopy . Biofouling