Abstract.
Although the ichthyotoxic mechanism of Chattonella marina is still unknown, several lines of evidence suggest that the reactive oxygen species (ROS), such as superoxide anion (O2 –), hydrogen peroxide (H2O2), and hydroxyl radical (·OH), produced by C. marina are involved in the mortality of fish exposed to this flagellate. Recently, we found that the cell-free supernatant prepared from C. marina, which is considered to contain the glycocalyx, showed NADPH-dependent O2 – generation. In this study, we prepared antiserum against the crude glycocalyx of C. marina. Using indirect immunofluorescence, it was confirmed that the antiserum specifically reacted with C. marina cells. In addition to C. marina, the antiserum also reacted with other raphidophycean flagellates such as Heterosigma akashiwo, Olisthodiscus luteus, and Fibrocapsa japonica, whereas no reactivity was observed against six other flagellate species tested. These results suggest that raphidophycean flagellates have common epitopes recognized by the antiserum. Interestingly, immunohistochemical analysis of paraformaldehyde-fixed gill lamellae from yellowtail exposed to C. marina revealed that the antiserum stained the surface of gill lamellae, while no such staining pattern was observed in control gill lamellae. These results suggest that the glycocalyx may be discharged when C. marina cells are inhaled into the fishes' mouths and then come into contact with the gill surface. Based on the present results, together with our previous findings, we propose that continuous accumulation of the discharged glycocalyx on the gill surface occurs during C. marina exposure, which may be responsible for the ROS-mediated severe gill tissue damage leading to fish death.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Electronic Publication
Rights and permissions
About this article
Cite this article
Kim, .DK., Okamoto, .T., Oda, .T. et al. Possible involvement of the glycocalyx in the ichthyotoxicity of Chattonella marina (Raphidophyceae): immunological approach using antiserum against cell surface structures of the flagellate. Marine Biology 139, 625–632 (2001). https://doi.org/10.1007/s002270100614
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s002270100614