Isoprene synthase variants for improved microbial production of isoprene

摘要

The present invention provides methods and compositions comprising at least one isoprene synthase enzyme with improved catalytic activity and/or solubility. In particular, the present invention provides variant plant isoprene synthases for increased isoprene production in microbial host cells. Biosynthetically produced isoprene of the present invention finds use in the manufacture of rubber and elastomers.

主权项

1. An isolated host cell comprising a heterologous polynucleotide sequence encoding an isoprene synthase variant in operable combination with a promoter, wherein said isoprene synthase variant comprises one or more amino acid substitution(s) at one or more amino acid residues corresponding to a poplar isoprene synthase having the sequence of SEQ ID NO: 120, wherein said substitution(s) are selected from the group consisting of V10M, F12S, T15A, E18G, V58I, V58F, L70Q, L70R, L70V, L70T, T71P, V79L, E89D, G94A, S119F, F120L, G127R, E175V, T212I, S257A, R262G, A266G, F280L, N297K, F305L, L319M, E323K, A328T, D342E, A359T, K366N, E368D, L374M, S396T, V418S, K438N, H440R, T442A, I449V, A469S, K500R, K505Q, G507S, S509N, F511Y, and N532K; and
wherein the variant is capable of more effectively converting dimethylallyl diphosphate (DMAPP) to isoprene, as compared to an isoprene synthase variant without a substitution.