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Using machine learning, molecular dynamics simulations, and density functional theory calculations we gain insight into the selectivity patterns of substrate activation by the cytochromes P450. In nature, the reactions catalyzed by the P450s lead to the biodegradation of xenobiotics, but recent work has shown that fungi utilize P450s for the activation of lignin fragments, such as monomer and dimer units. These fragments often are the building blocks of valuable materials, including drug molecules and fragrances, hence a highly selective biocatalyst that can produce these compounds in good yield with high selectivity would be an important step in biotechnology. In this work a detailed computational study is reported on two reaction channels of two P450 isozymes, namely the O-deethylation of guaethol by CYP255A and the O-demethylation versus aromatic hydroxylation of p-anisic acid by CYP199A4. The studies show that the second-coordination sphere plays a major role in substrate binding and positioning, heme access, and in the selectivity patterns. Moreover, the local environment affects the kinetics of the reaction through lowering or raising barrier heights. Furthermore, we predict a site-selective mutation for highly specific reaction channels for CYP199A4. [ABSTRACT FROM AUTHOR]

Molecular sieve films have been successfully employed in separation membranes and corrosion-resistant coatings in which the orientation is poised to enhance their performance. However, the simple synthesis of oriented molecular sieve films remains a challenge. In this study, we report an amine-assisted ionothermal strategy for the formation of in-plane oriented coatings with good anti-corrosion properties. Benefiting from the introduction of amine as a co-template with an ionic liquid solvent, the morphology was also controlled in the coatings. [ABSTRACT FROM AUTHOR]

Microscale covalent organic polymers with a unique 3D hollow wool ball-like morphology have been woven from 1D nanorods by a cascade emulsion strategy with a large surface area (284 m 2 g -1 ), which showed great potential for simultaneous removal ( Q max , 358.15 mg g -1 ) and fluorescent detection (detection limit, 8.0 μg L -1 ) of bisphenol A.