RESUMO
The original version of this article (Bartolo-Aguilar et al. 2017) was written and published including the first construction strategy of pLGC09, but not the final one. This error was pointed out by a reader and an analysis of sequences of parts of the plasmid corroborated this. The final construction strategy was reanalysed and confirmed the error. This error affected the text, Table 2, Fig. 1 and Additional files, but did not affect the results and conclusions stated in the paper. The authors regret that this error occurred in the original publication of the article. The corrected text, Table 2 and Fig. 1, and Additional files (Additional file 1. Construction strategy of pLGC09 and Additional file 2. Plasmid pLGC09) are given in this correction.
RESUMO
The production of recombinant biopharmaceutical proteins is a multi-billion dollar market. Protein recovery represents a major part of the production costs. Pichia pastoris is one of the microbial systems most used for the production of heterologous proteins. The use of a cold-induced promoter to express lytic enzymes in the yeast after the growth stage could reduce protein recovery costs. This study shows that a cold-shock can be applied to induce lysis of the yeast cells. A strain of P. pastoris was constructed in which the endogenous eng gene encoding a putative endo-ß-1,3-glucanase was overexpressed using the cold-shock induced promoter of the cctα gene from Saccharomyces cerevisiae. In the transgenic P. pastoris, the expression of eng increased 3.6-fold after chilling the cells from 30 to 4 °C (cold-shock stage) followed by incubation for 6 h (eng expression stage). The culture was heated to 30 °C for 6 h (ENG synthesis stage) and kept at 37 °C for 24 h (lysis stage). After this procedure the cell morphology changed, spheroplasts were obtained and cellular lysis was observed. Thus, a clone of P. pastoris was obtained, which undergoes autolysis after a cold-shock.