Fig. 1.
Expression and characterization of CLD-W and CLD-M. (A) Schematic representation of CLD expression system in E. coli. Two dotted arrows label the positions of two primers for inverse PCR to generate the mutant of PG3 CLD. (B) Analytical assays of recombinant proteins by MALDI-TOF mass spectrometry, and (C) CD spectra recorded from 190 to 250 nm. Δε corresponds to the variation of molar amino acid residue absorption expressed in M−1 cm−1. Spectra were taken at a peptide concentration of 0.3 mg/ml in water.