noun
actinomycetes; ray fungus
A group of filamentous bacteria. The term is often used in microbiology. Note the similar term 放線菌 (ほうせんきん) is more common for this meaning; 放射菌 is a less frequent variant.
See also: 放線菌 (ほうせんきん)
放射菌は土壌中に広く分布している。
Actinomycetes are widely distributed in soil.
この抗生物質は放射菌から発見された。
This antibiotic was discovered from actinomycetes.