Abstract

PEREZ-MARTINEZ, A.S.; BARBA DE LA ROSA, A.P.  and  DE LEON-RODRIGUEZ, A.. Heterologous expression of Trichoderma atroviride endochitinase ech42 in Pichia pastoris at low and high dissolved oxygen tensions. Rev. Mex. Ing. Quím [online]. 2014, vol.13, n.1, pp.93-101. ISSN 1665-2738.

The expression of recombinant Trichoderma atroviride endochitinase ech42 (rech42) in Pichia pastoris driven by the constitutive P_GAP promoter was tested at low (3%) and high (40%) dissolved oxygen tension (DOT) conditions. Maximum volumetric enzyme activities of 18,600±1053 and 12,330±1000 U1⁻¹ were attained at 3% and 40% DOT, respectively. Whereas maximum specific enzyme activities were 89.4±4.6 y 88.8±4.0 U mg⁻¹_protein. We found that conjunction of low DOT and the overexpression of rech42 affected the cell size of the P. pastoris but no the rech42 specific enzyme activity.

Keywords : chitin; cell size; recombinant endochitinase; oxygen-limited fermentation.