User:LannyPack/sandbox2

= Lophomonas =

Introduction
Lophomonas is a genus of single-celled parabasalids that is found in the hindgut of some cockroaches, termites, and crickets. Lophomonas’ unique pear-shaped body and tufted appearance due to its many flagella make it easily recognizable. Lophomonas is endocommensal to its host, meaning it is a beneficial symbiotic relationship for both organisms. Lophomonas helps its host in the digestion of lignocellulose, and in return receives a supply of food and shelter. Lophomonas has recently been subject to increased study due to its potential as a human pathogen affecting the respiratory system.

Etymology
First described by Stein in 1860, the name "Lophomonas" was likely derived from two Greek words: "lophos," used as a prefix meaning "crested" or "tufted" and "-monas," a suffix used to denote a ”unicellular organism." Together, the name was likely intended to refer to the appearance of the organism under a microscope, with a tuft or crest on its surface.

Type Species
Lophomonas blattarum Stein 1860

History
Lophomonas, among other multiflagellates, was first identified in the intestine of Blatta orientalis (common cockroach) by Stein in 1860. It is one of the earliest described genera in the group Parabasalia. The histology of Lophomonas was described using an optical microscope in 1911 and with a scanning and transmission electron microscope in 1990. The first detected case of Lophomonas infection in humans occurred in China in 1993. The genus has since been subject to increased study and is considered an “emerging protozoan disease” that primarily infects the pulmonary system.

Habitat and ecology
Lophomonas is primarily found in the gut of cockroaches, where it lives as an endocommensal organism. Commensal organisms are those that live in close association with another organism (the host), and obtain benefits from the relationship without causing harm to the host. In the gut of cockroaches, Lophomonas feeds on bacteria and other microorganisms that are present in the termite's digestive tract while also playing a crucial role in lignocellulose digestion. Lophomonas is adapted to survive in the highly acidic and anaerobic conditions that are found in the cockroach hindgut. While Lophomonas is primarily associated with cockroaches, it has also been found in the gut of other insects, including termites and crickets.

Morphology:
Lophomonas typically measures 20-60 μm in length and 12-20 μm in width. Lophomonas appears colourless under the microscope and generally exhibits an ovoid or pear-shaped cell body, with a long, tapering posterior end and a broad, flattened anterior end. The size and shape of Lophomonas is flexible however, and can vary depending on the species and environmental conditions. The cytoplasm appears grainy due to phagocytic vesicles. Cells appear “tufted” at the anterior end due to the 50 or more flagella which erupt from the calyx. Each emerging from a basal body embedded in the calyx, the flagella are unequal in length with longer ones emerging from the centre, and shorter ones emerging from the periphery of the basal body.

The calyx is a structure that is unique to Lophomonas. It is funnel or trumpet-shaped and extends down the central anteroposterior axis of the cell. The nucleus is contained within the calyx and appears as a prominent dark body that is slightly oval shaped and is situated in close proximity to the embedded basal bodies of the flagella. The calyx is surrounded by a “collar” of perinuclear tubules (once called the parabasal apparatus) that resembles, and functions as an equivalent to, the endoplasmic reticulum in other cells. The function of the calyx in Lophomonas is not well understood, but it is thought to play a role in the regulation of movement and the orientation of the cell. The microtubules that support the calyx may also be involved in the transport of materials within the cell and in the regulation of cell shape and structure.

Life cycle:
The life cycle of Lophomonas is not well understood, as little-to-no research has been conducted on the reproductive processes in live specimens of this genus. Based on observations of various smears, it appears that Lophomonas reproduces asexually through binary fission.

During binary fission, the cell elongates and the nucleus divides into two identical copies, followed by division of the cytoplasm and separation of the two daughter cells. The length of the cell division cycle and the frequency of cell division may vary depending on environmental conditions such as temperature, pH, and nutrient availability.

It is possible that Lophomonas may also undergo sexual reproduction, although this has not been observed directly. Some related organisms in the class Hypermastigia, such as Trichonympha, are known to undergo sexual reproduction through the fusion of gametes or the exchange of genetic material between cells.

Practical importance
Lophomonas is considered by some scientists to be an “emerging protozoan disease” in humans as it has recently been found in the respiratory tracts of individuals with asthma, tuberculosis, chronic obstructive pulmonary disease (COPD), and COVID-19. Research suggests that the presence of Lophomonas in the respiratory tract may contribute to the development or exacerbation of these respiratory conditions. It is believed that Lophomonas may trigger an inflammatory response in the airways and can lead to fevers, cough with thick mucus produced, respiratory insufficiency and even pulmonary abscesses.

The classification of Lophomonas as a human pathogen is still disputed with some scientists contesting that most reported Lophomonas infections were misdiagnosed due to limitations in the methodology of those studies (ex. Morphology the sole method of diagnoses).

List of Species
Lophomonas blattarum

Lophomonas striata