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- Actinomycetes are aerobic, though they generally are low-oxygen-utilizing bacteria. Actinomycets indicates an organism belonging to the Actinomycitales, a subdivision of the Prokaryotae Kingdom. Actino means ray in Greek and mycete means mushroom. (Actinomycetes were first regarded as a fungus.)
- Actinomycetes are Gram-positive organisms. This means they have a thicker layer of peptidoglycan in their cell wall than Gram-negative bacteria.
- Actinomycetes contain a cell wall. Flagella grows in and on the substrate. Another internal structure is thallus (a tissue like mass that grows in cultures). One more internal structure is mycelium (tangled mass of hyphae that is found in nature). Actinomycetes can be identified by their branching growth pattern that results in large threadlike structures. These filaments may break apart to form rods or spheroidal shapes, called bacillus. Some actinomycetes can form spores.
- Actinomycetes occur in soil. They are the primary decomposers of tough plant tissues, such as tree bark or cellulose.
- Most actinomycetes are aerobic. Very few have been known to grow in anaerobic conditions. Actinomycetes do not function well under particuarly acidic conditions or particuarly moist conditions.
- Actinomycetes reproduce by spores. One form of reproduction is Hyphal growth is followed by fragmentation and release of spores. Another form of reproduction is Conidia is when spores produce asexually on aerial fillaments.
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- From 1914 to 1939, Selman A. Waksman had been systematically screening soil bacteria and fungi. He was attempting to find an antibiotic for Tuberculosis. In 1939, at the University of California he discovered the effect of certain fungi, especially actinomycetes, on bacterial growth. Actinomycetes slowed bacterial growth because of the antibiotics they produce. In 1940, he was able to isolate an effective TB antibiotic, actinomycin. The only problem was this was too toxic for usage by humans and animals. Since then, numerous antibiotics have been created using actinomycetes.
- Actinomycets are helpful in breaking down plants, especially cellulose (The toughness in plants). Actinomycetes are very good at decomposing compost. They break down materials such as bark, paper, and plant stems. Actinomycetes take over during the last stage of decomposition. While they do this, they often produce antibiotics that prevent bacterial growth or kill other microscopic organisms that are threatening to them. They were first regarded as a type of fungus. This is shown in their name, actino (ray, gr.), mycetes (mushroom, fungus, gr.) Actinomycetes fix nitrogen from the air and convert it into a for that plants can use.
- Actinomycetes are effective as an antibiotic, and are very useful in breaking down compost. If actinomycetes weren't around, it would take a longer time for compost to decompose, and we would lack certain antibiotics.
- The "earthy" smell of soil is caused by actinomycetes. They are also especially important in the formation of hummus.
- Actinomycetes produce Streptomycin which is an antibiotic that prodeces... Spectinomycin, Neomycin, Tetracyclines, Chamydias, Rickettsias etc., Nystatin, Erythromycin, Legionella, and Chloramphenicol.
 - http://www.bearpathfarm.com/soil-food-web.htm
- Bear Path Farm
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