Cloning and expression of a functional core streptavidin in Pichia pastoris: Strategies to increase yield

• Autor(a) principal: Silveira, Wendel B. da
• Data de Publicação: 2012
• Outros Autores: Diniz, Raphael H. S., Passos, Flavia M. L., Casteluber, Marisa C. F., Damasceno, Leonardo M., Passos, Frederico J. V.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1002/btpr.1621; http://www.locus.ufv.br/handle/123456789/21779
• topic: Pichia pastoris; Streptadivin; Heterologous protein expression; Recycling of biomass; Aeration

Streptavidin is widely used as an analytical tool and affinity tag together with biotinylated surfaces or molecules. We report for the first time a simple strategy that yields high biomass of a Pichia pastoris strain containing a methanol induced core streptavidin (cStp) gene. Three factors were evaluated for biomass production: glycerol concentration, aeration, and feed flow rates in a bioreactor. Recycling of recombinant cells, either free or immobilized, was investigated during induction. Concentration of 2.0 M glycerol, feeding flow rate of 0.11 mL min−1, and aeration by air injection dispersed with a porous stone combined with agitation at 500 rpm were the set of conditions resulting into maximum biomass yield (150 g L−1). These parameters yielded 4.0 g L−1 of cStp, after 96 h of induction. Recombinant biomass was recycled twice before being discarded, which can reduce production costs and simplify the process. Immobilized P. pastoris biomass produced 2.94 and 1.70 g L−1 of cStp in the first and second induction cycle, respectively. Immobilization and recycling of recombinant P. pastoris biomass opens new possibilities as a potential strategy to improve volumetric productivity for heterologous protein expression.