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With potent herbicidal activity, biocatalysis synthesis of l-glufosinate has drawn attention. In present research, NAP-Das2.3, a deacetylase capable of stereoselectively resolving N-acetyl-l-glufosinate to l-glufosinate mined from Arenimonas malthae, was heterologously expressed and characterized. In Escherichia coli, NAP-Das2.3 activity only reached 0.25 U/L due to the formation of inclusive bodies. Efficient soluble expression of NAP-Das2.3 was achieved in Pichia pastoris. In shake flask and 5 L bioreactor fermentation, NAP-Das2.3 activity by recombinant P. pastoris reached 107.39 U/L and 1287.52 U/L, respectively. The optimum temperature and pH for N-acetyl-glufosinate hydrolysis by NAP-Das2.3 were 45 °C and pH 8.0, respectively. The Km and Vmax of NAP-Das2.3 towards N-acetyl-glufosinate were 25.32 mM and 19.23 μmol mg−1 min−1, respectively. Within 90 min, 92.71% of L-enantiomer in 100 mM racemic N-acetyl-glufosinate was converted by NAP-Das2.3. l-glufosinate with high optical purity (e.e.P above 99.9%) was obtained. Therefore, the recombinant NAP-Das2.3 might be an alternative for l-glufosinate biosynthesis. [ABSTRACT FROM AUTHOR]

In this work, we designed and synthesized a novel naphthalenediimide-based n-type conjugated polymer PNDICI, which bears asymmetric backbone containing a 3-chlorothiophene unit. The asymmetric structure associated with steric effects of the chlorine atom imparts remarkable solubility to PNDICI in various organic solvents, enabling the fabrication of all-polymer solar cells (all-PSCs) by using an environmentally friendly solvent of d-limonene. Combined with a novel pyrrolo[3,4-f]benzotriazole-5,7(6H)-dione based p-type conjugated polymer P2F-Si with deep highest occupied molecular orbital energy level, the resulting d-limonene-processed all-PSCs presents an impressively high open-circuit voltage of approaching 1.0 V, corresponding to a very small energy loss of 0.49 eV. Through further morphology optimization by using γ-valerolactone, we demonstrated an impressive device efficiency of 4.2%, which is among the best photovoltaic performance of devices processed using d-limonene and comparable to that processed by conventional solvent, suggesting the great promise of using greener solvent for fabricating high-performance all-PSCs. [ABSTRACT FROM AUTHOR]