Optimization of expression condition of hAD in D1 strain compared by fluorescence microscopy. (A&B) D1 hAD expression strain was cultured and induced with 3 different concentrations of IPTG, for 2 hours or 4 hours. The bacterial culture of hAD expression D1 strain were induced for 2 hours or 4 hours aliquoted, observed and recorded under bright field and red fluorescence in 40×magnification. Scale bar, 50μm for 40×magnification and 50μm for 100×magnification. I-a, 0.1mM IPTG induced; I-b, 0.5mM IPTG induced; I-c, 0.5mM IPTG induced.