Actinomycetes form a special order within the bacteria: thread-like structures, resembling hyphae (fungal threads). However, they are not fungi, as they do not contain a cell nucleus, nor does their cell wall contain cellulose or chitin, in contrast to the cell wall of fungi.
Actinomycetes like Streptomyces produce antibiotics, suppress soil fungi, parasitize fungal spores, and compete for nutrients. They also decompose tough organics (cellulose, lignin, chitin), forming stable humus that improves soil structure, CEC, and water balance.
Actinomycetes cannot tolerate acidic conditions well, with the most favorable pH values being between 6.5 and 8.0.