Proteomonas sulcata

Introduction

Described by Hill and Wetherbee; type species Proteomonas sulcata (marine; Hill and Wetherbee 1986).

Only one strain has been sequenced (Marin et al. 1998; Deane et al. 2002; Hoef-Emden et al. 2002). Proteomonas sulcata was the first cryptophyte for which a dimorphism was reported (Hill and Wetherbee 1986). In molecular phylogenies inferred from nucleomorph SSU rDNA sequences, this strain seems to be related to the other two PE545-containing clades with free nucleomorphs (Guillardia/Hanusia and Geminigera/Plagioselmis/Teleaulax genus complex), whereas its position is not resolved in nuclear SSU rDNA phylogenies (Hoef-Emden et al. 2002).

Characteristics

• Type of biliprotein: PE545
• Nucleomorph free in periplastidial space
• Dimorphic
• Light microscopy: reddish cryptophytes, one bilobed plastid with a pyrenoid, haplomorphs smaller than diplomorphs
• Ultrastructure of haplomorph: inner periplast component with hexagonal plates, surface covered by hexagonal scales, furrow only, non-keeled rhizostyle
• Ultrastructure of diplomorph: sheet-like inner periplast component, surface covered by fibrils and rosulate scales, furrow only, keeled rhizostyle

References

Deane JA, Hill DRA, Brett SJ, McFadden GI (2002) Cryptomonad evolution: Nuclear 18S rDNA phylogeny versus cell morphology and pigmentation. J. Phycol. 38: 1236-1244

Hill DRA, Wetherbee R (1986) Proteomonas sulcata gen. et sp. nov. (Cryptophyceae), a cryptomonad with two morphologically distinct and alternating forms. Phycologia 25: 521-543

Hoef-Emden K, Marin B, Melkonian M (2002) Nuclear and nucleomorph SSU rDNA phylogeny in the Cryptophyta and the evolution of cryptophyte diversity. J. Mol. Evol. 55: 161-179

Marin B, Klingberg M, Melkonian M (1998) Phylogenetic relationships among the Cryptophyta: analyses of nuclear-encoded SSU rRNA sequences support the monophyly of extant plastid-containing lineages. Protist 149: 265-276