Journal of Bioscience and Bioengineering, Vol.105, No.4, 335-340, 2008
Oxygen vectors used for S-adenosylmethionine production in recombinant Pichia pastoris with sorbitol as supplemental carbon source
In order to increase the yield of S-adenosylmethionine (SAM) in recombinant Pichia pastoris, a strategy of adding oxygen vectors and supplemental carbon sources was described. Three organic solutions were used as oxygen vectors for SAM accumulation at different concentrations and addition times. Firstly, n-hexane (0.5%) or n-heptane (1.0%) was added after 72 It of cultivation to improve SAM production. Carbon metabolism was scarce during the induction phase because of low methanol concentration. Secondly, sorbitol (1.2%), selected from three candidates (glycerol, lactic acid, and sorbitol), was used as the supplemental carbon source. The yield of SAM was improved significantly (53.261/0) at 1.0% n-heptane added at 72 h (48 h induction), 1.2% sorbitol added at 72, 96, and 120 h of cultivation and 1.0% methanol added every 24 h during cultivation.
Keywords:S-adenosylmethionine;fermentation;oxygen vectors;Pichia pastoris;supplemental carbon source