Impact of gene dosage and methanol concentration on Rhizopus chinensis recombinant lipase production in Pichia pastoris

Abstract:

The Rhizopus chinensis lipase genes was cloned and expressed in Mut⁺ methylotrophic Pichia pastoris with different gene dosage. The high-density fermentation of the recombinant Pichia pastoris with gene dosage of three (XY RCL-3), five (XY RCL-5) and six (XY RCL-6) was investigated on 7-liter fermenter. The impact of methanol concentration on Rhizopus chinensis lipase expression was also explored. Our results indicated that more Rhizopus chinensis lipase was produced in XY RCL-5 produced than that of XY RCL-6 and XY RCL-3 under the same conditions. When methanol concentration was controlled at 0.10%±0.02%, the enzyme activity of Rhizopus chinensis lipase produced by XY RCL-5 could achieve 12 500 U/mL, and the dry weight of XY RCL-5 and protein concentration could reach 204 g/L and 8.02 g/L, respectively.