OBSERVATIONS ON THE RESPIRATION OF TRYPANOSOMA CRUZI IN CULTURE

Measurement of Energy States of the Trypanosomatid Mitochondrion

The evaluation of mitochondrial functionality is critical to interpret most biological data at the (eukaryotic) cellular level. For example, metabolism, cell cycle, epigenetic regulation, cell death mechanisms, autophagy, differentiation, and response redox imbalance are dependent on the mitochondrial state. In case of parasitic organisms, such as trypanosomatids, it is very often important to have information on mitochondrial functionality in order to assess the mechanisms of actions of drugs being proposed for therapy. In this chapter we present a set of methods that together allow to evaluate with some precision the mitochondrial functionality in Trypanosoma cruzi and Trypanosoma brucei. We discuss how to determine O2 consumption, mitochondrial inner membrane potential, ATP production, and the endogenous production of reactive oxygen species.

Cultural and physiological observations on Trypanosoma rhodesiense and Trypanosoma gambiense. 1949

1. A diphasic medium of simple preparation is described for the indefinite cultivation of T. rhodesiense and T. gambiense. 2. The chief advantage of the medium is that it contains rabbit blood and thus obviates the necessity of using human blood. 3. The flagellates develop only to the proventricular stage; hence the cultures are noninfective. 4. The proventricular forms of both T. rhodesiense and T. gambiense consume sugar with the concomitant formation of acid. They are aerobic fermenters. 5. Very little, if any, ammonia is produced by the living parasites.

Strains and clones of Trypanosoma cruzi differ in their expression of a surface antigen identified by a monoclonal antibody

Four Trypanosoma cruzi strains and 50 clones derived from a total of 10 strains were assayed with a monoclonal antibody, WIC 29.26 Ab, for expression of an epitope previously demonstrated to be on the carbohydrate portion of a 72 000 Da surface glycoprotein of Y strain epimastigotes. WIC 29.26 Ab bound to only 2 of the 4 strains and 23 of the 50 clones tested. A group of 10 cloned isolates from one strain contained both reactive and non-reactive clones. Competitive inhibition studies with soluble extracts of the reactive and non-reactive isolates suggested that in addition to being absent from the surface membrane, the antigenic determinant is not synthesized by the non-reactive parasites. These data indicate that the epitope recognized by WIC 29.26 Ab is not present on all T. cruzi epimastigotes, and provide the first demonstration of clone-specific differences in a parasite antigen detected by a monoclonal antibody. No correlation was found between the reactivity of isolates with WIC 29.26 Ab and the previously investigated parameters of growth rate and modal volume.

Gas content of swim bladder of Wallago attu and oxygen consumption in Isoparorchis hypselobagri (Trematoda)

The swim bladder gas of Wallago attu contains O2 (22-58 mm Hg) and the presence or absence of Isoparorchis hypselobagri does not influence the O2 content of the swim bladder. Glucose increases the O2 consumption of I. hypselobagri by 50%. With the passage of in vitro culture time, the rate of O2 consumption gradually decreases to the extent of 64% on the 40th day. The optimal temperature for O2 consumption is 30 degrees C beyond which the rise in temperature is detrimental to the fish trematode as manifested by the decrease in their O2 consumption.