Henneguya salminicola

=Henneguya salminicola = Henneguya salminicola is a myxozoan parasite that primarily infects salmonid fish. It is notable for being one of the few multicellular organisms that does not rely on oxygen for survival. This unique characteristic has made it a subject of interest in the study of anaerobic life forms.

Taxonomy

Henneguya salminicola belongs to the phylum Cnidaria, class Myxosporea, and family Myxobolidae. It is closely related to other myxozoans, which are parasitic cnidarians.

Morphology

The organism is characterized by its spore stage, which is the most commonly observed form. The spores are microscopic and have two polar capsules, which are used to attach to the host tissue. The spores are typically oval-shaped and contain a sporoplasm that houses the parasite's genetic material.

Life Cycle

Henneguya salminicola has a complex life cycle involving two hosts: a fish and an annelid worm. The parasite's spores are released into the water when an infected fish dies. These spores are then ingested by annelid worms, where they develop into actinospores. The actinospores are released into the water and infect new fish hosts, completing the cycle.

Host Interaction

The primary hosts for Henneguya salminicola are salmonid fish, including species such as Oncorhynchus mykiss (rainbow trout) and Salmo salar (Atlantic salmon). The parasite typically infects the muscle tissue of the fish, forming cysts that can be visible to the naked eye. These cysts are often referred to as "milky flesh" or "tapioca disease" due to their appearance.

Anaerobic Metabolism

One of the most intriguing aspects of Henneguya salminicola is its ability to survive without oxygen. Unlike most multicellular organisms, it lacks mitochondria, the organelles responsible for aerobic respiration. Instead, it relies on anaerobic metabolic pathways to generate energy, a trait that is rare among multicellular organisms.

Impact on Fisheries

While Henneguya salminicola is generally not harmful to humans, it can have economic impacts on fisheries. The presence of cysts in fish muscle can make the fish less marketable, affecting the commercial value of infected fish stocks.

Research and Studies

Recent studies have focused on the genetic and metabolic adaptations that allow Henneguya salminicola to thrive in anaerobic environments. Understanding these mechanisms could provide insights into the evolution of anaerobic life and potential applications in biotechnology.

See Also

• Myxozoa
• Anaerobic organisms
• Salmonid fish diseases

External Links

• Henneguya salminicola Genome Study
• Henneguya salminicola Impact on Fisheries

NIH genetic and rare disease info

• NIH info on Henneguya salminicola

Henneguya salminicola is a rare disease.