The present invention provides for a fuel compositions are provided comprising a hydrogenation product of a tricyclic sesquiterpene (epi-isozizaene, pentalenene, or -isocomene) and a fuel additive. Methods of making and using the fuel compositions are also disclosed.

The present application relates to a modified isoprene synthase that has an isoprene synthetic activity and has at least one mutation of an amino acid residue in the amino acid sequence of SEQ ID NO: 4, an amino acid sequence having one or several amino acid substitutions, deletions, insertions or additions in the amino acid sequence of SEQ ID NO: 4, or an amino acid sequence having 90% or more identity to the amino acid sequence of SEQ ID NO: 4. The modified isoprene synthase is useful for preparing isoprene monomers in improved yields.

Disclosed are production of terpenoid compound and the strain used by, which belong to the technical field of bioengineering. The disclosure constructs an engineered strain of Serratia marcescens in production of hemiterpenes or monoterpenes, and the engineered strain of S. marcescens can produce linalool, isoprene, isopentenol, 1,8-cineole, -pinene, pinene, -terpinene, geraniol, (+)-limonene, ()-limonene, myrcene, -ocimene, sabinene, ()--bisabolol, farnesol, longifolene, valencene, -elemene, farnesene, patchoulol, pentalenene, and -santalene. In a 30 L fermenter, the yield of linalool produced by the engineered strain of S. marcescens is 40.72 g.Math.L.sup.1.