Repurposing a bacterial prolidase for organophosphorus hydrolysis: Reshaped catalytic cavity switches substrate selectivity.

Enzyme promiscuity is critical to the acquisition of evolutionary plasticity in cells and can be recruited for high-value chemical synthesis or xenobiotic degradation. The molecular determinants of substrate ambiguity are essential to this activity; however, these details remain unknown. Here, we performed the directed evolution of a prolidase to enhance its initially weak paraoxonase activity.

Statistical optimization of alkaline protease production from Penicillium citrinum YL-1 under solid-state fermentation.

Proteases from halotolerant and halophilic microorganisms were found in traditional Chinese fish sauce. In this study, 30 fungi were isolated from fermented fish sauce in five growth media based on their morphology. However, only one strain, YL-1, which was identified as Penicillium citrinum by internal transcribed spacer (ITS) sequence analysis, can produce alkaline protease.