from
The Collaborative International Dictionary of English v.0.48
actinomycetes \actinomycetes\ n.
1. branched gram-positive bacteria, often found in soil, some
of which are pathogenic for humans and animals.
Note: some species have been found to produce metabolites
which are useful in medicine. Many species of these
bacteria have been isolated and extensively screened by
pharmaceutical companies and university research groups
for production of useful therapeutic agents. Among the
agent produced by actinomycetes are tetracyclines,
streptomycin, avermectin, and thienamycin
[WordNet 1.5]