Brief communication - Phaeodactylum tricornutum is a bona fide calcifying diatom

Blundell-Hunter, G.; Paoli, L.; Marsden, O.; Kazamia, E.; Mozzanega, P.; Diaz-Ramos, A.; Baiden, N.; McGibbon, E.; Kumari, E.; Samuels, R.; Collard, J.; Waite, J.; Hu, I.

doi:10.64898/2026.10.12.758572

bioRxiv · 10.64898/2026.10.12.758572

Brief communication - Phaeodactylum tricornutum is a bona fide calcifying diatom

Blundell-Hunter, G.·Paoli, L.·Marsden, O.·Kazamia, E.·Mozzanega, P.·Diaz-Ramos, A.·Baiden, N.·McGibbon, E.·Kumari, E.·Samuels, R.·Collard, J.·Waite, J.·Hu, I.

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Abstract

Phaeodactylum tricornutum is an unusual member of the clade of diatoms, eukaryotic marine brown algae that possess a distinct cell wall made of silica. Phaeodactylum is a rare exception in diatom biology in that it does not require silica throughout its whole life cycle. Here, we demonstrate that Phaeodactylum has a calcifying activity, which is highly unusual in unicellular eukaryotes.

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Blundell-Hunter, G., Paoli, L., Marsden, O., Kazamia, E., Mozzanega, P., Diaz-Ramos, A., Baiden, N., McGibbon, E., Kumari, E., Samuels, R., Collard, J., Waite, J., Hu, I.. 2026-10-14. Brief communication - Phaeodactylum tricornutum is a bona fide calcifying diatom. https://doi.org/10.64898/2026.10.12.758572

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