Sterol Composition of the Peridinin-Containing Dinoflagellate Gertia stigmatica, a Member of the Kareniaceae without a Canonical Haptophyte-Derived Plastid

Sterols of the aberrant plastid, Kareniacean dinoflagellate Asterodinium gracile: Chemotaxonomic overlap with amphisterol‐producing Amphidinium carterae

“…(2007) and Leblond et al . (2023): Similar to all other Kareniaceae with aberrant plastids, A. gracile possesses 4α‐methyl‐substituted, Δ 8(14) ‐nuclear‐unsaturated major sterols, namely sterols 5 and 6 . However, as described below, these particular sterols are not common to other identified sterols in the Kareniaceae.…”

“…2019), has also been shown to possess 4‐desmethyl sterols, including ergosta‐5,8(14),22E‐trien‐3β‐ol (C 28:3 ; also known as 24‐methylcholesta‐5,8(14),22E‐trien‐3β‐ol) and cholesta‐5,8(14),22E‐trien‐3β‐ol (C 28:3 ), which both possess a Δ 8(14) nuclear unsaturation, yet also have a Δ 5 nuclear unsaturation (Leblond et al . 2023). Ergosta‐5,8(14),22E‐trien‐3β‐ol is also found in K. papilionacea (Mooney et al .…”

“…It was grown autotrophically to a density of approximately 1 × 10 4 cells mL −1 and harvested according to the same conditions as used for G. stigmatica (Leblond et al . 2023), namely being grown in triplicate at 20°C under a 14:10 h light/dark photocycle at an irradiance of approximately 50 μmol photons m −2 s −1 of white light (one‐half cool white fluorescent bulbs and one‐half LED bulbs within the incubator). Although we have only examined one set of growth conditions, as based on the work of Volkman et al .…”

“…(2019) and Leblond et al . (2023). Relative retention times to cholesterol were determined per Jones et al .…”

“…2007), including G. stigmatica (Leblond et al . 2023), cholestanol has only been found in G. stigmatica . Cholestanol is a minor sterol in some other dinoflagellates outside of the Kareniaceae [see discussion in Leblond et al .…”