Produção de estreptavidina recombinante pela levedura Pichia pastoris

• Autor(a) principal: Fonseca, Marisa Cristina da
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5386
• topic: Estreptavidina; Pichia pastoris; Biomassa; Purificação; Proteínas recombinantes; Reatores químicos; Biotina; Streptavidin; Pichia pastoris; Biomass; Purification; Recombinant proteins; Chemical reactors; CNPQ::CIENCIAS BIOLOGICAS::MICROBIOLOGIA::MICROBIOLOGIA APLICADA

Streptavidin has been exploited as affinity tag to isolate protein in biotinilated columns. Recombinant Pichia pastoris KM71/Stp strains containing the streptavidin core gene were cultured in fed-batch generating 150 g L-1 biomass. This biomass was achieved with a simpler and shorter process that has never been reported. The yeast was pre-cultured into 50 mL minimum medium with glycerol as only carbon source at 25ºC and 250 rpm. After 12 hours incubation, the culture was transferred to a bioreactor with 200 mL of the same initial A600 0,2. After 24 hours incubation the culture was fed-batch with glycerol and basal salts medium to reach 400 mL. The glycerol concentration of 2.0 moles. L-1 combined with a flow of 0.11 mL. min-1 and aeration by air injection dispersed with a porous stone and magnetic stirring of 500 rpm were the set of conditions to yield maximum biomass. The streptavidin concentration at the supernatant of the free cell culture at 96 hours, the maximum induction period, has achieved 4.0 g. L-1, reducing to 3.2 and 0.87 g. L-1 with two reutilizations. At the same time period the immobilized culture yield 75 %, 50 % and 80% less at the first, second and third culture utilization, respectively. The immobilization and recycling of recombinant P. pastoris biomass can prove to be a potential strategy to improve volumetric productivity.