Isolation and Chemical Composition of Dinoflagellate Nuclei*

Abstract
SYNOPSIS: Nuclei were isolated fromPeridinium cinctum. Peridinium trochoideum, Gyrodinium cohnii(Cryptothecodinium cohnii) andGymnodinium nelsoni.The nuclei ofG. cohnii, P. trochoideumandG. nelsoniwere found to contain ∼ 6.9, 34 and 143 picograms of DNA respectively. The ratios to DNA of RNA, acid‐soluble and acid‐insoluble protein forG. cohniiwere 0.32, 0.13 and 0.99, respectively. The corresponding values forP. trochoideumwere 0.22, 0.08 and 1.22, while those forG. nelsoniwere 0.21, 0.10 and 1.09. The chemical composition of dinoflagellate nuclei is compared and contrasted with that of typical eukaryotic nuclei. The culture of these difficult organisms also is discussed.