Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 3871

W.H. Johnson, M.D. Brennan, D.K. Berard, J.H. Morrow, and K.D. Hudson; Proteins and Polysaccharides in the Nutrition of Paramecium multimicronucleatum. J.Protozool. 27(3):332-336, 1980

Reprint

In File

Notes

Paramecium multimicronucleatum has been cultured for 20 years on a medium of salts, vitamins, amino acids, fatty acids, ribosides, and stigmasterol plus a little nondialyzable fraction (NDF) of baker's yeast. Fractionations of NDF identified 2 essentials: (a) in a fraction <100,000 daltons which contained much protein and replaceable by ovalbumin and (b) in a fraction of >300,000 daltons; this fraction contained much polysaccharide, replaceable by glycogen, which is >300,000 daltons. For 2 years now P. multimicronucleatum has grown well with ovalbumin and glycogen replacing NDF. Besides ovalbumin, concanavalin A satisfies the protein requirement; this lectin attaches to sugar residues in glycogen. Studies with a fluorescent dye, PGA-1A, a stilbene derivative, provides further evidence for the polysaccharide requirement. This dye attaches to polysaccharides; when added to glycogen, and this in turn is added to a culture containing ovalbumin, fluorescent blue vacuoles appear within 2-3 hr. When dye + glycogen were added to a culture without ovalbumin, no fluorescent vacuoles were found. A protein appears involved in formation of food vacuoles; this fits the pattern of endocytosis described in recent reviews. Besides glycogen, mannan gave good growth. Dextrin and amylopectin gave only fair growth through 7 serial transfers; glucose, maltose and amylose did not sustain growth. Strain 51 of P. tetraurelia, which grows well in NDF medium, grows well when NDF is replaced with ovalbumin and glycogen.