ETUDE DES COMPLEXES DE PIGMENTS CHLOROPHYLLIENS D'EUGLENA GRACILIS AU COURS DE LA CROISSANCE ET A L'ETAT ADULTE

Une tude des cellules d'Euglnes et de leurs extraits prparsavec les ultra-sons, chauffs ou non chauffs (quelques heures 35), montre que:

1. le chauffage ne dtruit pas la chlorophylle de faon notable;
2. en prsence d'alcool, un agrgat de chlorophylle ayant unebanded'absorption 740–750 mµ apparait dans lesextraitsd'Euglnes ges de plus de 11 jours;
3. les jeunesEuglnes et les Euglnes ges et chauffes ne peuventformerl'agrgat absorbant aux grandes longueurs d'ondes;
4. deux outrois complexes chlorophylliens diffrents sont impliqusdansla formation des agrgats qui absorbent 740 mµ.

¹ Travail rendu possible par l'attribution d'une bourse d'tudede l'universit de Montral l'un des auteurs (DE K.) et l'octroid'une subvention de recherches (A-1196) du Conseil Nationaldes Recherches du Canada.     

CHLOROPLAST PIGMENTS OF CHLOROMONADOPHYCEAE

The chloroplast pigments of 2 species of Chloro-monadophyceae have been examined. Both Gonyo-stomum semen and Vacuolaria virescens possessed only one chlorophyll, chlorophyll a. Gonyostomum contained 4 carotenoids, but not fucoxanthin and peridinin. Vacuolaria also possessed 4 carotenoids which have been identified as β-carotene and the 3 xanthophylls commonly found in the Xanthophyceae (as represented by Tribonema aequale). These are antheraxanthin, lutein monoepoxide, and an hydroxy lutein monoepoxide-like xanthophyll. The taxonomic significance of these findings, the first for the Chloromonadophyceae, is discussed.     

PHOTOLYTIC LIPIDS FROM VISUAL PIGMENTS

A method is described for the preservation of iodopsin, the labile photopigment of daylight vision, by freeze drying in vacuo. The lipids released by the action of light on rhodopsin and iodopsin are found to be similar and to possess a labile absorption spectrum in chloroform, with a rising peak at about 390 mµ and a declining peak in the region of 470 mµ. After the change is complete the absorption spectrum resembles closely that of retinene.