Cytological, genetic, and biochemical characteristics of an unusual non‐Chlorella photobiont of Stentor polymorphus collected from an artificial pond close to the shore of Lake Biwa, Japan. Issue 1 (6th December 2012)

• Record Type: Journal Article
• Authors: Hoshina, Ryo; Sato, Emi; Shibata, Aika; Fujiwara, Yuko; Kusuoka, Yasushi; Imamura, Nobutaka
• Is Part Of: Phycological research. Volume 61:Issue 1(2013:Jan.)
• Page Start: 7
• Page End: 14
• Publication Date: 2012-12-06
• Subjects: Algae -- Japan -- Periodicals; Algae -- Periodicals; 579.8
• DOI: 10.1111/j.1440-1835.2012.00664.x
• Languages: English
• ISSNs: 1322-0829

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p> <italic>Stentor polymorphus</italic> (Müller) Ehrenberg (Heterotrichea, Ciliophora) is a trumpet‐form ciliate with endosymbiotic green algae (photobionts). Previous reports have indicated that this photobiont has a form typical of <italic>Chlorella</italic> Beijerinck (Trebouxiophyceae), with one chloroplast and a distinct pyrenoid. We collected <italic>S. polymorphus</italic> from an artificial pond on the shore of Lake Biwa in Japan. Microscopic examination demonstrated that there was no pyrenoid in the photobiont, and thus we analyzed the cytological, genetic, and biochemical characteristics of these algal cells. Cultured photobionts were smaller than those <italic>in hospite</italic>. Phylogenetic analyses placed the photobiont within the genus <italic>Mychonastes</italic> Simpson and Van Valkenburg, a chlorophycean alga occurring in fresh/brackish waters that lacks pyrenoids. <italic>Mychonastes</italic> provided little photosynthate to its host; the quantity of carbohydrate amounted to only 2% of that provided to <italic>Paramecium bursaria</italic> (Ehrenberg) Focker by its photobiont.</p> </abstract>