TECHNOLOGY FOCUS - BIOLOGY - Preferred Components: The cyanobacterium is a Agmenellum, Anabaena, Anabaenopsis, Anacystis, Aphanizomenon, Arthrospira, Asterocapsa, Borzia, Calothrix, Chamaesiphon, Chlorogloeopsis, Chroococcidiopsis, Chroococcus, Crinalium, Cyanobium, Cyanocystis, Cyanospira, Cyanothece, Cylindrospermopsis, Cylindrospermum, Dactylococcopsis, Dermocarpella, Fischerella, Fremyella, Geitleria, Geitlerinema, Gloeobacter, Gloeocapsa, Gloeothece, Halospirulina, Iyengariella, Leptolyngbya, Limnothrix, Lyngbya, Microcoleus, Microcystis, Myxosarcina, Nodularia, Nostoc, Nostochopsis, Oscillatoria, Phormidium, Planktothrix, Pleurocapsa, Prochlorococcus, Prochloron, Prochlorothrix, Pseudanabaena, Rivularia, Schizothrix, Scytonema, Spirulina, Stanieria, Starria, Stigonema, Symploca, Synechococcus, Synechocystis, Thermosynechococcus, Tolypothrix, Trichodesmium, Tychonema or Xenococcus species. The cyanobacterium is cultured phototrophically. The amount of the fatty acid or its derivative produced is at least 10% more than the amount of the fatty acid or its derivative produced by a cyanobacterium cultured under identical conditions that does not comprises an exogenous nucleic acid molecule encoding a transcription factor domain protein, but is otherwise identical in all respects to the recombinant cyanobacterium. Preferred Method: The method further comprises isolating the free fatty acid or its derivative from the cyanobacteria or from the growth media.    TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preparation: No preparation method is given. Preferred Components: The nucleic acid sequence encodes a cyanobacterial transcription factor domain protein. The transcription factor domain protein is a homologous or heterologous protein. The transcription factor domain protein comprises an amino acid sequence having at least 60% sequence identity to SEQ ID NOs: 2, 4, 6, 10, 12, 14, or 16 (each comprising fully defined sequence of 148, 546, 391, 105, 109, 244 or 244 amino acids, respectively as given in the specification). The amino acid sequence has at least 85% sequence identity to SEQ ID NOs: 4, 6, 10, 12, 14, or 16. The exogenous nucleic acid molecule further comprises a promoter operably linked to the sequence encoding the transcription factor domain protein. The cyanobacterium further comprises: a nucleic acid molecule encoding a thioesterase and/or lipase polypeptide having lipolytic activity; and at least one additional exogenous gene, encoding a protein for the production of a fatty acid or its derivative or an enzyme comprising an acetyl coenzyme A (CoA) carboxylase, a ketoacyl-CoA synthase, an acyl-CoA synthetase, a fatty acyl-CoA/aldehyde reductase, an alcohol-forming fatty acyl-CoA reductase, a fatty aldehyde- forming fatty acyl-CoA reductase, an acyl-ACP reductase, a carboxylic acid reductase, a fatty aldehyde reductase, an alcohol acetyl transferase, an acyl-CoA alcohol transacylase, an acyltransferase, a wax synthase, a fatty aldehyde decarbonylase, or a fatty acid decarboxylase. The isolated or recombinant nucleic acid molecule operably linked to an heterologous promoter. The promoter is inducible. The nucleic acid molecule is in an expression or an integration vectors. EXAMPLE - No suitable example given.