Bodo saltans
Encyclopedia
Bodo saltans, also published as Pleuromonas jaculans, is a free-living nonparasitic species of kinetoplastid
flagellate
protozoa
n that is distinguished by the organism's feeding upon bacteria. B. saltans can be found widely distributed throughout the world in both freshwater and marine environments.
B. saltans is a single-celled bean-shaped organism 4 to 5 micrometers in length. It has two flagella: a short anterior projecting flagellum and a longer posterior-projecting flagellum without hairs (acronematic) that extends beyond the length of the cell. B. saltans secures itself to the substrate of its aquatic habitat by the tip of a posterior flagellum. Flexing of the posterior flagellum results in a twitching, jumping movement that is characteristic of this species. This type of movement is appears similar to the undulating membrane of the sexually-transmitted pathogen Trichomonas vaginalis
and can result in a false-positive diagnosis in cases where B. saltans is a contaminant in test samples, especially if a nonsterile saline solution
has been used.
Phylogenetic analysis
of the mitochondrial
RNA editing process and inferred protein sequences in B. saltans appear to show that B. saltans diverged early on from the evolutionary line of kinetoplastids and that this species of bodonid is more closely related to the trypanosomatids than at least two species of parasitic bodonids of the genus Cryptobia
.
Analysis based on the sequence of the topoisomerase II
(topo II) gene provides evidence that B. saltans is a predecessor of the trypanosomatids. Commonly, the molecules of mitochondrial DNA
in eukaryotes is circular and replication and transcription result in topological stress that is mitigated by enzymes called topoisomerases. Kinetoplastids possess a single mitochondrion with what is perhaps the most complex network of mitochondrial "kDNA" in small and large circular forms. As a consequence, mitochondrial genes for topoisomerases are available in high quantities that make it an attractive focus of genetic study. It is also the significance of the enzyme class of topoisomerases to the function of kinetoplastids that makes the topo genes a target for the medical treatment of trypanosomial and leishmania
l diseases.
In one phylogenetic tree
, the parasitic kinetoplastids included two separate groups of species – C. helicis and T. borreli in one group and the trypanosomatids in the other. The non-parasitic free-living B.saltans and B. uncinatus were distributed among the two groups which implies that the bodonids such as B. saltans, may not have been predecessors of the parasitic species. Other studies show that the trypanosomatids evolved relatively late among the kinetoplastids and constitute a monophyletic group, but that the bodonids may be paraphyletic.
Kinetoplastid
The kinetoplastids are a group of single-cell flagellate protozoa, including a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments...
flagellate
Flagellate
Flagellates are organisms with one or more whip-like organelles called flagella. Some cells in animals may be flagellate, for instance the spermatozoa of most phyla. Flowering plants do not produce flagellate cells, but ferns, mosses, green algae, some gymnosperms and other closely related plants...
protozoa
Protozoa
Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...
n that is distinguished by the organism's feeding upon bacteria. B. saltans can be found widely distributed throughout the world in both freshwater and marine environments.
B. saltans is a single-celled bean-shaped organism 4 to 5 micrometers in length. It has two flagella: a short anterior projecting flagellum and a longer posterior-projecting flagellum without hairs (acronematic) that extends beyond the length of the cell. B. saltans secures itself to the substrate of its aquatic habitat by the tip of a posterior flagellum. Flexing of the posterior flagellum results in a twitching, jumping movement that is characteristic of this species. This type of movement is appears similar to the undulating membrane of the sexually-transmitted pathogen Trichomonas vaginalis
Trichomonas vaginalis
Trichomonas vaginalis is an anaerobic, flagellated protozoan, a form of microorganism. The parasitic microorganism is the causative agent of trichomoniasis, and is the most common pathogenic protozoan infection of humans in industrialized countries. Infection rates between men and women are the...
and can result in a false-positive diagnosis in cases where B. saltans is a contaminant in test samples, especially if a nonsterile saline solution
Saline (medicine)
In medicine, saline is a general term referring to a sterile solution of sodium chloride in water but is only sterile when it is to be placed intravenously, otherwise, a saline solution is a salt water solution...
has been used.
Phylogenetic analysis
Phylogenetics
In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...
of the mitochondrial
Mitochondrion
In cell biology, a mitochondrion is a membrane-enclosed organelle found in most eukaryotic cells. These organelles range from 0.5 to 1.0 micrometers in diameter...
RNA editing process and inferred protein sequences in B. saltans appear to show that B. saltans diverged early on from the evolutionary line of kinetoplastids and that this species of bodonid is more closely related to the trypanosomatids than at least two species of parasitic bodonids of the genus Cryptobia
Cryptobia
-Introduction:Cryptobia species are protozoa that can lead to disease in fish. C. branchialis is an ectoparasite that lives on the skin or gills of fish, and the other four pathogenic species are endoparasites that live in the circulatory system or intestines.Marine and freshwater fish can be...
.
Analysis based on the sequence of the topoisomerase II
Topoisomerase
Topoisomerases are enzymes that regulate the overwinding or underwinding of DNA. The winding problem of DNA arises due to the intertwined nature of its double helical structure. For example, during DNA replication, DNA becomes overwound ahead of a replication fork...
(topo II) gene provides evidence that B. saltans is a predecessor of the trypanosomatids. Commonly, the molecules of mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
in eukaryotes is circular and replication and transcription result in topological stress that is mitigated by enzymes called topoisomerases. Kinetoplastids possess a single mitochondrion with what is perhaps the most complex network of mitochondrial "kDNA" in small and large circular forms. As a consequence, mitochondrial genes for topoisomerases are available in high quantities that make it an attractive focus of genetic study. It is also the significance of the enzyme class of topoisomerases to the function of kinetoplastids that makes the topo genes a target for the medical treatment of trypanosomial and leishmania
Leishmania
Leishmania is a genus of Trypanosomatid protozoa, and is the parasite responsible for the disease leishmaniasis. It is spread through sandflies of the genus Phlebotomus in the Old World, and of the genus Lutzomyia in the New World. Their primary hosts are vertebrates; Leishmania commonly infects...
l diseases.
In one phylogenetic tree
Phylogenetic tree
A phylogenetic tree or evolutionary tree is a branching diagram or "tree" showing the inferred evolutionary relationships among various biological species or other entities based upon similarities and differences in their physical and/or genetic characteristics...
, the parasitic kinetoplastids included two separate groups of species – C. helicis and T. borreli in one group and the trypanosomatids in the other. The non-parasitic free-living B.saltans and B. uncinatus were distributed among the two groups which implies that the bodonids such as B. saltans, may not have been predecessors of the parasitic species. Other studies show that the trypanosomatids evolved relatively late among the kinetoplastids and constitute a monophyletic group, but that the bodonids may be paraphyletic.