''Encephalitozoon intestinalis'' is a
parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
.
[ It can cause ]microsporidiosis
Microsporidiosis is an opportunistic intestinal infection that causes diarrhea and wasting in immunocompromised individuals ( HIV, for example). It results from different species of microsporidia, a group of microbial (unicellular) fungi.
In HI ...
.[
It is notable as having one of the smallest ]genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...
among known eukaryotic
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacte ...
organisms, containing only 2.25 million base pairs.sequenced
In genetics and biochemistry, sequencing means to determine the primary structure (sometimes incorrectly called the primary sequence) of an unbranched biopolymer. Sequencing results in a symbolic linear depiction known as a sequence which suc ...
in 2010.[
''E. intestinalis'' originally named Septata intestinalis, was reclassified based on morphologic, antigenic
and molecular similarities with other species of the genus Encephalitozoon. Recently, Some domestic
and wild animals have been found to be naturally infected with ''E. intestinalis'' and some other
microsporidian species.][Centers for Disease Control and Prevention. 2013.]
''E. intestinalis'' is transmitted in contaminated water. It causes Gastro-Intestinal tract infection which
subsequently leads to diarrhea and circulates to the ocular, genitourinary
The genitourinary system, or urogenital system, are the organs of the reproductive system and the urinary system. These are grouped together because of their proximity to each other, their common embryological origin and the use of common pathwa ...
and respiratory tracts.
Research has proven that ''E. intestinalis'' infection can increase host cell nuclear mutation rate.
Disease
''Microsporidia'' are obligate intracellular opportunistic fungi that cause significant pathology in
immunocompromised (simply put: having an impaired immune system) hosts. Like other
obligate intracellular pathogens, ''microsporidia'' exert significant stress on infected host cells.
''Microsporidia'' infection alters host cell cycle regulation and can lead to development of
multinucleated host cells.
Genome
Compared to ''E. cuniculi'' which encodes about 2000 massive genes at 2.9 Mbp, ''E. intestinalis'' had a reduced gene complement and genome size (2.3 Mbp) because of a high degree of host dependency. ''E. intestinalis'' lack large gene blocks of sequence in its subtelomeric regions unlike ''E. cuniculi''. However, ''E. intestinalis'' and ''E. cuniculi'' share a conserved gene content, order and density
over most of their genomes
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding gen ...
which have similar GC content. They also contain the same
complement of transfer RNAs and ribosomal RNAs.
Detection
The assay is adaptable to the clinical laboratory and represents the first real‐time PCR assay
designed to detect Encephalitozoon species. Melting temperature analysis of the amplicons
allows for the differentiation of three Encephalitozoon species (E. intestinalis, E. cuniculi, and E.hellem).
Prevention and Treatment
Frequent washing of hands and limited exposure to animals is highly recommended especially for
people with immunesystem deficiency. Treatment of Microsporidia can vary depending on the
species involved. Intravenous fluid administration, electrolyte repletion, dietary and nutritional
regimens can be helpful to patients with diarrhea while antiretroviral therapy can help improve
immune system function.[Steven Doerr, MD Melissa Conrad Stöppler, MD.]
References
{{DEFAULTSORT:Encephalitozoon Intestinalis
Parasitic fungi
Microsporidia