In this work, applications of carbon-carbon bond hydrolases, especially ?-diketone hydrolases, in organic synthesis were studied. C-C bond hydrolases are enzymes capable of catalysing the hydrolytic cleavage of selected ketonic substances: ?-Diketone hydrolases, for example, hydrolyse C-C bonds of 1,3-diketones into a ketone and a carboxylate products. The main emphasis of this work was laid on a ?-diketone hydrolase 6-oxo camphor hydrolase (OCH) from Rhodococcus sp. which is a member of the crotonase superfamily and catalyses a reverse Claisen condensation of non-enolisable, prochiral 1,3-diketones yielding a keto acid product as a single enantiomer. In our work, OCH was shown to have a remarkable stability towards a variety of organic solvents and to be moderately thermostable. The stability and activity of OCH in organic solvents allowed the combination of the OCH catalysed hydrolysis with a simultaneous lipase catalysed esterification for the synthesis of methyl (3-oxocyclohexyl)acetate in an enantiopure form. This process was further utilized in combination with a reductive amination catalysed by ?-transaminases.OCH is a strictly (S)-selective catalysts for which no stereocomplementary counterpart has been described. Site-directed mutagenesis studies were carried out for investigating the structural determinants of the enantioselectivity and stereopreference of this enzyme. Additionally, nature?s diversity was sampled for discovering stereocomplementary hydrolytic activity. The results indicated that (R)-selective C-C-hydrolases exist in nature.In addition to the ?-diketone hydrolases, two Friedel-Crafts hydrolases, 2,4-diacetylphloroglucinol hydrolase from Pseudomonas fluorescens and phloretin hydrolase from Eubacterium ramulus were studied. The organic solvent tolerance of all the C-C-hydrolases prompted the study of alternative nucleophiles as substrates as well as C-C-bond formation studies.