Figure 2

Analysis of production of anti-oxazolone single-chain antibody fragment scFv _Ox . A) Inducible expression of scFv_ox in strain RULOx. Soluble scFv_ox in supernatants of YNB-cultures pregrown in glucose, 0, 2 and 4 hrs after induction by lactose was detected by Western blotting. The reference lane contains 15 ng of purified scFv_ox. B) Constitutive expression of scFv_ox in strain RULOx/D802 (Klgal80Δ). Upon disruption of the KlGAL80 gene higher levels of soluble scFv_ox were present in supernatants of glucose- than lactose-grown cells. The reference lane contains 5 ng of purified scFv_ox. C) Long-term cultivation in glucose or glycerol medium (2% and 3% initial concentration, respectively) of the Klgal80 mutant strain expressing scFv_ox (RULOx/D802 strain). Cell density (squares) is plotted with oxazolone-binding activity (triangles) and protein content (diamonds) in culture supernatant as determined by ELISA and SDS-PAGE, respectively, against the pure reference protein.