Question

what is Streptomycetes bacteria and what does it do when comes in contact with moisture / water / rain?

Answer 1

this is a bacteria which is responsible for the slow good smell after rainfall...the smell derives from an oil exuded by certain plants during dry periods, whereupon it is absorbed by clay-based soils and rocks. During rain, the oil is released into the air along with another compound, geosmin, a metabolic by-product of certain actinobacteria, which is emitted by wet soil, producing the distinctive scent; ozone may also be present if there is lightning