Enzymes of the Ornithine‐Arginine Metabolism of Trypanosomatids of the Genus Crithidia*

Abstract

SYNOPSIS. Twelve strains of Crithidia, which fall into 8 species, were tested for occurrence of enzymes of ornithine‐arginine metabolism. The following enzymes were investigated: arginase, ornithine carbamoyltransferase, argininosuccinate lyase, citrulline hydrolase, arginine deiminase and urease. Arginase and argininosuccinate lyase were found in all species. Citrulline hydrolase was also found in all but the 2 strains carrying endosymbiotes C. deanei and C. oncopelti. On the other hand, ornithine carbamoyltransferase was found only in these 2 strains. Arginine deiminase and urease were absent in all strains. The existence of a common enzymatic pattern for species of the genus Crithidia is thus reported.

The heterogeneity of choanomastigote-shaped trypanosomatids as analyzed by their kDNA minicircle size: taxonomic implications

“…The heterogeneity amongst the choanomastigote trypanosomatids has already been shown by several biochemical and/or molecular approaches, such as the analysis of ornithine metabolism enzymes, surface proteins, isoenzymes, mini-exon gene repeats, restriction sites in kDNA and rDNA followed by hybridizations and karyotypying (Figueiredo et al 1978;Galinari and Camargo 1978;GoncË alves de Lima et al 1982;Motta et al 1991;Camargo et al 1992;Pacheco et al 1994;Teixeira et al 1995;Sousa et al 1996;Clark 1997;Fernandes et al 1997;Pires et al 1997;Hollar et al 1998). In several of these reports, similar species groupings have been proposed, based on the particular characters analyzed.…”

Morphological, Biochemical and Molecular Characterization of Herpetomonas samuelpessoai camargoi n. subsp., a Trypanosomatid Isolated from the Flower of the Squash Cucurbita moschata

“…Enzymes of ornithine‐arginine metabolism can be correlated with the trypanosomatid genera and are considered to be of taxonomic value (Camargo et al 1987; Figueiredo et al 1978; Yoshida et al 1978). The squash isolate was negative for arginase and positive for OCT—a profile comparable to that described for Herpetomonas (Yoshida et al 1978).…”

“…The squash isolate was negative for arginase and positive for OCT—a profile comparable to that described for Herpetomonas (Yoshida et al 1978). Lack of arginase is a common feature of Phytomonas, Herpetomonas , and some Leptomonas species (Camargo et al 1992; Camargo et al 1987; Figueiredo et al 1978). Activity of the OCT is particu larly detected in Herpetomonas spp., but too few Phytomonas spp.…”

Vectors of Plant Parasites of the Genus Phytomonas (Protozoa, Zoomastigophorea, Kinetoplastida)

“…Difficulties in morphological distinction between Leptomonas, Herpetomonas, and Phytomonas led to a search for alternative criteria (155)_ Enzymes of the arginine-ornithine metabolism helped to separate the genus Leptomonas from Herpetomonas and Phytomonas (15,18,36,156). Monoclonal antibodies specific for Phytomonas were used to recognize members of this genus among insect isolates (129,140) and restriction enzyme analysis of ribosomal genes and synthetic oligonucleotide rDNA probes have been used with the same objective (17).…”