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Figure 2 | Microbial Cell Factories

Figure 2

From: Directed evolution of single-chain Fv for cytoplasmic expression using the β-galactosidase complementation assay results in proteins highly susceptible to protease degradation and aggregation

Figure 2

Lactose phenotype correlates with the soluble expression levels Phenotype of strain TG1 transformed with the pPM170 plasmid containing a series of scFv with different soluble expression levels in E. coli cytoplasm. The scFv13, 13R1, 13R2, 13R3 and 13R4 are described in [28]. T- and T+ are TG1 transformed with the pTrc99A and pUC119 plasmids, respectively. 173S1 is a spontaneous lac+ mutant isolated from TG1(pPM173) (see text and Fig. 1). A) Lactose phenotype on MacConkey lactose plates. The ability of the cell to use lactose is proportional to the depth of the red coloration. B) βgal activity present in the cytoplasm of the cells measured using Miller's whole cell assay [30].

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