[11] At the same time, a research team at the Universidade de Brasilia reported the biochemical properties and structural details based on transmission electron microscopy.

"[13] The bacterial nature of the endosymbiont was confirmed in 1977 when it was shown that it could be killed by treating with an antibiotic chloramphenicol,[14] and that it helps the host in synthesising the amino acid arginine from ornithine.

In 1991, Maria Auxiliadora de Sousa and Suzana Corte-Real at the Instituto Oswaldo Cruz proposed a new genus Angomonas for the species.

The cell membrane of the protozoan host contains an 18-domain β-barrel porin, which is a characteristic protein of Gram-negative bacteria, and unusual of eukaryotes.

[19] Cardiolipin is a typical lipid of bacterial membranes; phosphatidylcholine, on the other hand, is mostly present in symbiotic prokaryotes of eukaryotic cells.

For symbiotic adaptation, the protozoan host has undergone alterations such as reduced paraflagellar rod, which is required for full motility of the bacterial flagella.

[22] While the protozoan has its separate mitochondria that provide electron transport system for the production of cellular energy, the ATP molecules are produced through its glycosomes.

In return the protozoan offers its enzymes for the complete metabolic pathways for the biosynthesis of amino acids, lipids and nucleotides, that are absent in the bacterium.

[26] The bacterium has highly reduced genome compared to its related bacterial species, lacking many genes essential for its survival.

[28] A bacterium-less protozoan exhibits reduced gene activities; particularly those involved in oxidation-reduction process, ATP hydrolysis-coupled proton transport and glycolysis are stopped.

[36] The entire reproduction takes about 6 hours in an ideal culture medium; thus, a single protozoan is able to produce 256 daughter cells in a day, though it can differ slightly under its natural habitat.

The endosymbiont contains enzymes and metabolic precursors that complete essential biosynthetic pathways of the host protozoan, such as those in the urea cycle and the production of haemin and polyamine.