Bioprocess efficiency in Rhizopus oryzae lipase production by Pichia pastoris under the control of PAOX1 is oxygen tension dependent. Issue 12 (December 2016)

• Record Type: Journal Article
• Authors: Ponte, Xavier; Montesinos-Seguí, José Luis; Valero, Francisco
• Is Part Of: Process biochemistry. Volume 51:Issue 12(2016:Dec.)
• Page Start: 1954
• Page End: 1963
• Publication Date: 2016-12
• Subjects: Pichia pastoris -- Fed batch -- Oxygen tension -- Rhizopus oryzae lipase -- AOX1 promoter -- Recombinant protein; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2016.08.030
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: Effect of DO on P. pastoris P AOX1 -based fed batch cultures producing ROL. Productivity and specific rates were maximal at moderate DO. Low oxygen tension did not favor substrate uptake, growth and productivity. Yields kept rather constant versus DO, excepting product to biomass yield. Productivity, yield, and titer could be optimized controlling DO. Abstract: Dissolved oxygen (DO) has been stated as a key parameter for Pichia pastoris (Mut + ) cultures growing on methanol. DO set point (DOSP ) – between 5 and 50% air saturation – with time-varying oxygen transfer rate (OTR) was investigated during the induction phase of fed batch cultures producing the heterologous Rhizopus oryzae lipase (ROL). DO around 25% was found to be the best operating condition in terms of ROL total productivity, with 4-fold increase in respect to DOSP of 5% (minimum value), and also corresponded with the highest specific rates of growth (μ), methanol consumption ( qS ), oxygen uptake ( qO2 ), carbon dioxide production ( qCO2 ) and ROL activity production ( qP ). However, the highest overall product yield ( Y * P/X ) was obtained around DOSP of 10%, with an increase of 45% compared with maximal DOSP studied (50%). Specific rates and Y * P/X were lower at the extremes of the DO range tested. The results validate that oxygen tension is essential to improve bioprocess efficiency in ROL production and enhances reliability of the system by keeping DO at optimal conditions. Productivity and yield can be optimized, thus reducing oxygen supply and energy requirements, even for different target proteins although presenting different DO optimal values.