Compositions and methods for producing isoprene

Recombinant fungal cells capable of producing isoprene, the cells comprising a heterologous nucleic acid encoding an isoprene synthase polypeptide, wherein the cells (i) produce greater than about 400 nmole/gwcm/hr of isoprene, (ii) convert more than about 0.002 molar percent of the carbon that the cells consume from a cell culture medium into isoprene, or (iii) have an average volumetric productivity of isoprene greater than about 0.1 mg/Lbroth/hr.