NOVELTY - Method for biosynthetic production of 1-alkenes, involves culturing an engineered microorganism in a culture medium, where the engineered microorganism comprises a recombinant 1-alkene synthase and produces 1-alkenes, and the amount of 1-alkenes produced by the engineered microorganism is greater than the amount produced by an identical microorganism cultured under identical conditions, but lacking the recombinant 1-alkene synthase.    USE - The method (M1) is useful for biosynthetic production of 1-alkenes, preferably 1-nonadecene and 1-octadecene. The method (M2) is useful for biosynthetic production of olefins, preferably 1-octadecene (all claimed). The alkenes are useful as lubricant and surfactant, and in fuel.    ADVANTAGE - The 1-alkenes and olefins can be mass produced.    DETAILED DESCRIPTION - Method for biosynthetic production of 1-alkenes, involves (a) culturing an engineered microorganism in a culture medium, where the engineered microorganism comprises a recombinant 1-alkene synthase and produces 1-alkenes, and the amount of 1-alkenes produced by the engineered microorganism is greater than the amount produced by an identical microorganism cultured under identical conditions, but lacking the recombinant 1-alkene synthase, or (b) (i) culturing an engineered microorganism in a culture medium, where the engineered microorganism comprises a modification which reduces the activity of an A1174 hydrolase originated from Cyanobacterium, and (ii) exposing the microorganism to light and carbon dioxide, where the exposure results in the production of alkenes by engineered microorganism, where the alkenes comprise 1-alkenes. INDEPENDENT CLAIMS are included for the following: (1) method (M2) for biosynthetic production of an olefin, involves culturing a Cyanobacterium in a culture medium, where the Cyanobacterium has a 1-alkene synthase activity and the culture medium comprises a exogenous fatty acid, and exposing the engineered Cyanobacterium to light and carbon dioxide, where the exposure results in the production of an olefin by the Cyanobacterium and the amount of the olefin produced is greater than the amount produced by an identical Cyanobacterium, cultured under identical conditions but in the absence of the exogenous fatty acid; (2) engineered Cyanobacterium, where the Cyanobacterium comprises a mutation in an A1174 hydrolase and the mutation reduces the activity of the hydrolase; and (3) engineered cell for the production of olefins, where the cell comprises a recombinant nonA gene, and the activity of the protein encoded by the nonA gene is greater than the activity of the protein in an otherwise identical cell lacking the recombinant nonA gene.