Porphyrin Rings and Phospholipids: Stimulators of Cloning Efficiency in Certain Species of Tetrahymena

Abstract

Species of Tetrahymena, including T. vorax, T. thermophila, T. pyriformis, and T. pigmentosa, were tested for cloning efficiency in proteose peptone and in synthetic nutrient media to which were added hemin, protoporphyrin IX, chlorophyllin, or asolectin, an impure mixture of phospholipids. All species could be cloned with high efficiency in the crude media. In unsupplemented synthetic medium the cloning efficiencies were 0-10%, around 50%, around 50%, and 90-100% for T. thermophila, T. vorax, T. pyriformis, and T. pigmentosa, respectively. The first three were all stimulated to 90-100% by addition of the porphyrin or phospholipid compounds mentioned above. Uroporphyrin III and coproporphyrin I and III had no effect. We suggest that cells unable to form clones suffer from a lack of cellular energy. This situation may be alleviated by our additions, certain porphyrin rings may be built into cytochromes and phospholipids may be used as fuel. Thus, the synthetic media used so far for these ciliates have not been optimal.

Inhibition of the Rumen Ciliate Entodinium caudatum by Antibiotics

“…The tested growth factors included fetal bovine serum (1%, v/v), stigmasterol (1 μg/ml), hemin (0.767 μM), and bovine serum albumin (0.005%, w/v), all of which have been used in developing axenic cultures of ciliate protozoa by other researchers (Yamin, 1978; Wagener and Pfennig, 1987; Schousboe et al, 1992; Mori et al, 2011). All growth factors were added at the concentrations recommended in the above studies or at concentrations slightly modified based on a preliminary study.…”

Cell survival and multiplication The overriding need for signals: from unicellular to multicellular systems

“…A second set includes hemin, protoporphyrin IX, and sodium nitroprusside (an NO-releasing compound) [7, 16,17]. They all play a role in activating a cytosolit, "soluble", in contrast to a "particulate", membrane-bound guanylate cyclase in mammalian cells [ 181. Guanylate cyclase is a heme-containing enzyme.…”

Signalling in cell growth and death: adequate nutrition alone may not be sufficient for ciliates

“…[These authors coined the term "probiotics" for their growth promoters, in contradistinction to antibiotics, but the term has not been adopted.] The structural homology of TGSF to mammalian and other growth factors needs to be looked into, since a wider range of exogenous nutrient and non-nutrient molecules can "kick-start" cell proliferation in the manner described by Schousboe et al (1992). Included among the positive substances are sterols, asolectin, tetra-decanol (but not dodecanol), dipalmytoyl phosphatidylcholine (which has undergone extensive "dissection" to find the active moiety of the molecule , porphyrin, hemin, triphorbol esters, diacylglyc-erol and croton oil (Le.…”