Hydrogenosomes in a mixed isolate of Isotricha prostoma and Isotricha intestinalis from ovine rumen contents.
1. Both Isotricha intestinalis and I. prostoma possess microbody-like organelles, with a highly granular appearance. 2. These organelles, which are sedimentable at 10(5) g-min, bear no morphological similarity to mitochondria, but are enzymatically similar to organelles possessed by certain other anaerobic protozoa and termed hydrogenosomes. 3. The hydrogenosomes isolated from a preparation of mixed isotrichs bear a closer similarity to those isolated from the other rumen holotrich. Dasytricha ruminantium, than those recently identified in a mixed entodiniomorph preparation, or the trichomonads, in that the enzyme malate dehydrogenase (decarboxylating) is non-sedimentable and phosphoacetyl transferase together with acetate kinase are involved in the transformation of acetyl CoA to acetate. 4. The results enable a scheme of acetate, CO2 and H2 formation from carbohydrates to be proposed and extends the number of protozoa known to possess this organelle.
D000818:Animals; D016798:Ciliophora / Q000378:metabolism / Q000648:ultrastructure*; D006859:Hydrogen / Q000378:metabolism*; D006867:Hydrolases / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism; D012417:Rumen / Q000469:parasitology*; D012756:Sheep / Q000469:parasitology*; D013347:Subcellular Fractions / Q000378:metabolism
D006859:Hydrogen; D010088:Oxidoreductases; D006867:Hydrolases