NOVELTY - An isolated polypeptide (P1) derived from botryococcene synthase, having a specific amino acid sequence, and capable of producing a triterpenoid hydrocarbon, is new.    USE - For producing a triterpenoid hydrocarbons, preferably botryococcene or dehydrobotryococcene, useful for biofuels, bioplastics, pharmaceuticals, food additives, industrial chemicals or specialty chemicals (all claimed), also as feedstock for hydrocracking in oil refinery to produce e.g. petrol, kerosene or diesel.    ADVANTAGE - The polypeptide and nucleic acid encoding the polypeptide provide the microorganisms that have faster growth, produce high levels of hydrocarbons, and that can facilitate commercialization of triterpenoid hydrocarbons production.    DETAILED DESCRIPTION - An isolated polypeptide (P1) derived from botryococcene synthase is new. The polypeptide (P1) comprises an amino acid sequence selected from: amino acid sequence having 227 amino acids as given in the specification (SEQ ID NO:41), amino acid sequence having 397 amino acids as given in the specification (SEQ ID NO:71), amino acid sequence having 392 amino acids as given in the specification (SEQ ID NO:72), or amino acid sequence having 162 amino acids as given in the specification (SEQ ID NO:73); or has at least 70% sequence identity, or is a functional fragment of any of these sequences. INDEPENDENT CLAIMS are included for the following:    (1) new isolated nucleic acid molecule (N1) encoding the polypeptide (P1);    (2) new vector (V1) comprising the nucleic acid molecule (N1);    (3) new vector (V1) deposited as V11/011086 or V11/011087;    (4) new recombinant non-human organism (B1) capable of producing a triterpenoid hydrocarbon, and comprising the nucleic acid molecule (N1), or the vector (V1);    (5) producing (M1) a triterpenoid hydrocarbon, involving growing the recombinant organism (B1) to produce the triterpenoid hydrocarbon;    (6) a triterpenoid hydrocarbon produced by the method (M1);    (7) producing (M2) an intermediate of a biofuel, a bioplastic, a pharmaceutical, a food additive, an industrial chemical or a specialty chemical, involving growing the recombinant organism (B1) to produce a triterpenoid hydrocarbon, harvesting the triterpenoid hydrocarbon from the organism, and producing the intermediate from the triterpenoid hydrocarbon; and    (8) new intermediate produced by the method (M2).