Artificial antibody-antigen-directed immobilization of α-amylase to hydrolyze starch for cascade reduction of 2-nitro-4-methylphenol to 2-amino-4-methylphenol

Nitrophenol is a hazardous substance that poses a threat to the environment and human health, and its treatment has attracted widespread attention. The purpose of this study is to establish an environmentally friendly α-amylase system for the hydrolysis of starch to reduce nitrophenol to aminophenol through cascade reactions. The α-amylase system was obtained through artificial antibody-antigen-directed immobilization, including the synthesis of artificial antibodies, synthesis of artificial antigens, and affinity assembly. In this process, catechol and protocatechuic aldehyde were used to prepare artificial antibodies and artificial antigens respectively through polymerization and Schiff base reactions. Then, artificial antibodies captured the catechol in the artificial antigen structure to form immobilized α-amylases. Compared with free α-amylase, the immobilized α-amylase showed a good reusability and excellent regenerative ability. Subsequently, the immobilized α-amylase were used in the reaction of catalyzing starch hydrolysis to synthesize 2-amino-4-methylphenol, and the yield of 2-amino-4-methylphenol was 58.88 ± 0.19 %. After 5 consecutive catalytic reactions, a yield of 47.61 ± 1.27 % can still be achieved.

Hydroxylammonium derivatives for selective active-site lysine modification in the anti-virulence bacterial target DHQ1 enzyme

The first example of a hydroxylammonium derivative that causes a specific covalent modification of the active-site lysine residue of an aldolase enzyme, which is a promising target for anti-bacterial drug discovery, is reported.

ECBS & ICBS 2015 Joint Meeting: Bringing Chemistry to Life

The European Chemical Biology Society (ECBS) and the International Chemical Biology Society (ICBS) recently organized a joint meeting in Berlin. This meeting had more than 250 participants. Four keynote lectures were given by Timothy Mitchison, David Tirrell, Carolyn Bertozzi and Jason Chin; in addition there were 13 invited speakers, 20 selected oral talks and 30 talks selected from 90 posters. The meeting was divided into six topics: chemoproteomics, epigenetics, conjugates for target delivering, anti-infectives, molecular imaging and probing the structure, and function of post-translational modifications. The highlights of the meeting are presented in this report.

Specific chemical modification of bacterial type I dehydroquinase – opportunities for drug discovery

Type I dehydroquinase (DHQ1) is a class I aldolase enzyme that catalyzes the reversible dehydration of 3-dehydroquinic acid to form 3-dehydroshikimic acid by multistep mechanism that involves the formation of Schiff-base species. DHQ1 is present in plants and several bacterial sources but it does not have any counterpart in human cells. It has been suggested that DHQ1 may act as a virulence factor in vivo and therefore a promising target in the search for new antivirulence agents to combat widespread antibiotic resistance. This review covers recent progress in the structure-based design and chemical modifications caused by selective irreversible inhibitors. Computational studies aimed at understanding the experimentally obtained covalent modifications and inhibitory potencies of these inhibitors are also described.