Microbiology: Symbiotic Relationships in Microorganism Mutualism

Symbiotic Relationships Involving Microorganism

Commensalism

• Demodex, a tiny mite, lives in human hair follicles and sebaceous glands, especially in eyelashes and eyebrows, without harming the host.

Mutualism

• Humans have a mutualistic relationship with many microorganisms in their indigenous microbiota.
• Escherichia coli, an intestinal bacterium, obtains nutrients from blood materials and produces vitamins (e.g., vitamin K) that benefit the host.
• Some indigenous microbiota prevent colonization by pathogens and overgrowth by opportunistic pathogens.
• Protozoa in termites' intestines break down wood molecules into absorbable nutrients, and the termite provides food and a warm, moist environment for the protozoa.
• Lichens, composed of an alga or cyanobacterium and a fungus, demonstrate mutualism, where the fungus uses energy from the alga's photosynthesis, and the fungal cell walls protect the alga from desiccation.

Parasitism

• Parasitism is a symbiotic relationship that benefits the parasite and harms the host.
• Not all parasites cause disease; some take only the necessary nutrients without harming the host.
• "Smart" parasites coexist with their hosts, while "dumb" parasites can kill their hosts and need to find a new host or die.
• Certain parasites, like Trypanosoma gambiense, always cause disease and can lead to death, as in African sleeping sickness.

Explore the concept of symbiotic relationships in microbiology and parasitology, focusing on mutualistic interactions between microorganisms. Learn about the example of protozoa living in the intestine of termites and their role in breaking down wood for termite nutrition.