STUDIES ON THE RED AND BLUE FORMS OF THE PIGMENT OF BLEPHARISMA*

Abstract

Abstract— –The intracellular pigment of the ciliate protozoan Blepharisma in the presence of oxygen sensitizes the cells to bright visible light (2700 foot candles (fc)). Illumination of the cells with dim visible light (200 fc) changes the color of the pigment to blue‐gray; such cells are no longer sensitive to bright visible light. The pigment which exists in granules can be extruded by cold treatment and is slowly regenerated. The suspension of red cells, the extruded pigment from them and an ethanol extract of the pigment all have very similar absorption spectra. Illumination of the red pigment in ethanol converts it to the blue form of the pigment but only if oxygen is present, indicating a photooxidation. The pigment can be oxidized in darkness to the blue form by ozonation. A suspension of blue cells, the extruded pigment from them and an ethanol extract from them, all have similar absorption spectra. The pigments in red and blue form are very similar spectrophotometrically and in solubility in three species of Blepharisma studies: B. americanum, B. intermedium and B. japonicum. The purified pigment has strong absorption in the far (200–300 nm) ultraviolet (u.v.) and may serve as a screen against damaging U.V. radiation, especially as Blepharisma shows poor photoreactivation.

PHOTOMOVEMENT RESPONSES OF THE HETEROTRICHOUS CILIATE Blepharisma Japonicum

“…The absorption characteristics of the red main pigment (Fig. 7) are very similar to those reported by Sevenants (196.5) and by Giese and Grainger (1970). Compared to the red pigment, only very small amounts of the black and the yellow pigments can be obtained.…”

Amethystin, the Coloring Principle of Stentor amethystinus

“…Stentor and Blepharisma are heterotrich ciliates (protozoa) prevalent in lakes, ponds, and marine environments. Some species are brightly colored by pinkish, red, blue, violet, or brown pigments located predominantly in granules that are arranged in stripes just below the cell surface, , The compounds responsible are structurally related to hypericin, the coloring principle of St. John’s Wort ( Hypericum perforatum ), which, most remarkably, is also stored in “granules” embedded in the leaves and petals of the plant, , and the fringelites, fossil pigments from a Jurassic sea lily. , …”

“…Thus, stentorin C ( 1a ), the blue pigment isolated from Stentor coeruleus , has been identified as the 3,3′-diisopropyl analogue of fringelite D with the alkylation pattern proven by total synthesis . Maristentorin from Stentor dinoferus shows yet another, though questionable, alkylation pattern. , In contrast, the pinkish blepharismin ( 2 ) from Blepharisma japonicum resembles protohypericin with the gap in the ring system bridged by a p -hydroxybenzylidene group. , From cultures kept in daylight, or on subsequent irradiation of blepharismins ( 2 ) in the presence of oxygen, oxyblepharismins ( 3 ) were isolated, and its stentorin-like structure was elucidated . Both compounds were found as a mixture of homologues with R 1 , R 2 = Et, i-Pr, R 3 = H, Me.…”

Defense Function of Pigment Granules in the Ciliate Blepharisma japonicum against Two Predatory Protists,Amoeba proteus (Rhizopodea) and Climacostomum virens (Ciliata)

“…The mechanism of the defense function of pigment granules in the light is made more complicated by the fact that light changes blepharismin to oxyblepharismin (Giese and Zeuthen, 1948;Giese and Grainger, 1970;Ghetti et al, 1992;Watanabe et al, 1995: Spitzner et al, 1998. We found that oxyblepharismin also has intrinsic toxicity and phototoxicity and that it also plays a role in the defense function of the pigment granules in B. japonicum .…”

“…The mutant albino of B. japonicum appeared spontaneously in the laboratory among wild-type red cells (Chunosoff et al ., 1965). It contains only a minute amount of the red pigment blepharismin and looks white (Chunosoff et al ., 1965;Giese and Grainger, 1970). For more details about stocks of Blepharisma , see Harumoto et al ., 1998.…”