Two streptomycete isolates, PA-31088 and PA-39504, were found to produce new carbapenem antibiotics, asparenomycins A, B and C. Strain PA-31088 was identified as a new species of Streptomyces and the name Streptomyces tokunonensis sp. nov. proposed. Strain PA-39504 was identified as Streptomyces argenteolus.