Thiamphenicol

Zerovalent iron (Fe⁰)-based Fenton-like technology has great potential for treating recalcitrant organic pollutants (ROPs) in wastewater. However, rapidly and precisely manufacturing Fe⁰-based materials with the desired geometries is challenging. Herein, novel three-dimensional printed Fe⁰ (3DP-Fe⁰) and bimetallic 3DP-Ni/Fe⁰ were customized by 3D printing for efficient Fenton-like degradation of florfenicol (FLO), a typical antibiotic in wastewater. 3DP-Ni/Fe⁰ with hydrogen peroxide (H₂O₂) exhibited superior reactivity toward FLO than 3DP-Fe⁰, generating hydroxyl radicals (·OH) and atomic hydrogen to achieve >90% dehalogenation and >70% total organic carbon removal within 10 min. The resulting degradation intermediates possessed lower antibacterial activity than FLO and did not cause resistance gene proliferation in activated sludge. The Fenton-like activity of 3DP-Ni/Fe⁰ was similar across different shapes but increased with increasing porosity and size. Compared with powdered Ni/Fe⁰, 3DP-Ni/Fe⁰ exhibited faster electron transfer during Fe(II)/Fe(III) cycling, which increased the utilization efficiency of dissolved Fe²⁺ and H₂O₂ for ·OH production. Moreover, 3DP-Ni/Fe⁰ could be reused >150 times, 5-fold more than powdered Ni/Fe⁰, owing to its lower metal ion release and Fe⁰ depletion. 3DP-Ni/Fe⁰ with H₂O₂ can also efficiently remove chemical oxygen demand from real wastewater and other ROPs (e.g., acetaminophen, carbamazepine, thiamphenicol, and tetrabromobisphenol A).

Acetyl-CoA is an essential central metabolite in living organisms and a key precursor for various value-added products as well.However, the intracellular availability of acetyl-CoA limits the efficient production of these target products due to complex and strict regulation.Here, we proposed a new acetyl-CoA pathway, relying on two enzymes, threonine aldolase and acetaldehyde dehydrogenase (acetylating), which can convert one L-threonine into one acetyl-CoA, one glycine, and generate one NADH, without carbon loss.Introducing the acetyl-CoA pathway could increase the intracellular concentration of acetyl-CoA by 8.6-fold compared with the wild-type strain.To develop a cost-competitive and genetically stable acetyl-CoA platform strain, the new acetyl-CoA pathway, driven by the constitutive strong promoter, was integrated into the chromosome of Escherichia coli.We demonstrated the practical application of this new acetyl-CoA pathway by high titer production of beta-alanine, mevalonate, and N-acetylglucosamine.At the same time, this pathway achieved a high-yield production of glycine, a value-added commodity chem. for the synthesis of glyphosate and thiamphenicol.This work shows the potential of this new acetyl-CoA pathway for the industrial production of acetyl-CoA-derived compounds