Expression of Pisum sativum defensin 1 (Psd1) in shaking flasks and bioreactor cultivations of recombinant Pichia pastoris at different pHs

• Autor(a) principal: Larentis,A. L.
• Data de Publicação: 2004
• Outros Autores: Almeida,M. S., Cabral,K. M. S., Medeiros,L. N., Kurtenbach,E., Coelho,M. A. Z.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Chemical Engineering
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322004000200004
• topic: Pichia pastoris; Pisum sativum Defensin 1; recombinant DNA; fed-batch; modeling; pH

The methylotrophic yeast Pichia pastoris was used to produce the recombinant Pisum sativum defensin (rPsd1), a small peptide from pea seeds that has a high level of antifungal activity. The plasmid rPsd1/pPIC9 was integrated into the yeast genome and methanol was used to induce expression and secretion of the recombinant Psd1, at 30º C in a fed-batch mode. The effects of different pH conditions and process scale-up were evaluated using a Monod-type model where dissolved oxygen was considered the limiting substrate. Parameter estimation showed that the process could be improved by expressing rPsd1 in a 1000 mL bioreactor at pH 4. Structural and functional analyses revealed that the recombinant Psd1 is very similar to the native one.