What greets my nose is a dark, familiar smell of earth, rich and dank and ripe. The smell brings back warm spring evenings and freshly plowed midwestern soil. Actinomycetes are microorganisms that are a sort of transitional group between bacteria and fungi. Like fungi, they produce tendril-like hyphae. But they also have cell walls, like bacteria.
Actinomycetes are intriguing characters.
They are able to decompose some fairly complex organic compounds. They eat tough substances such as cellulose and chitins. They also produce antibiotics. Streptomycin, for example, comes from a strain of actinomycetes. Although actinomycetes give healthy soil one of its signature smells, they are merely part of an enormous cast of colorful characters.