The genus
forms a distinct phyletic line in the 16S rRNA gene
tree; produces a branched, non-fragmenting substrate
mycelium which carries aerial hyphae that differentiate
into globose or spherical spore vesicles; has
meso-diaminopimelic acid and madurose in the peptidoglycan;
contains di- and tetra-hydrogenated menaquinones
with nine isoprene units; complex mixtures
of iso-, anteiso-, saturated, unsaturated and 10-methyl
branched fatty acids; diphosphatidylglycerol, phosphatidylethanolamine,
phosphatidylglycerol, phosphatidylinositol
and glucosamine—containing polar lipids
as major components; and has a DNA base composition
within the range 69–71 mol% GC (Quintana and
Goodfellow 2012). These authors also reported that
Streptosporangium species can be distinguished
from one another by using a battery of biochemical,
nutritional and morphological criteria.