We report a previously unknown process in which anoxygenic phototrophic bacteria use nitrite as an electron donor for photosynthesis. We isolated a purple sulfur bacterium 98% identical to Thiocapsa species that stoichiometrically oxidizes nitrite to nitrate in the light. Growth and nitrate production strictly depended on both light and nitrite. This is the first known microbial mechanism for the stoichiometric oxidation of nitrite to nitrate in the absence of oxygen and the only known photosynthetic oxidation in the nitrogen cycle. This work demonstrates nitrite as the highest-potential electron donor for anoxygenic photosynthesis known so far.
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http://dx.doi.org/10.1126/science.1139478 | DOI Listing |
J Am Chem Soc
January 2025
Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Ribonucleotide reductase (RNR) is essential for DNA synthesis and repair in all living organisms. The mechanism of RNR requires long-range radical transport through a proton-coupled electron transfer (PCET) pathway spanning two different protein subunits. Herein, the direct PCET reaction between the interfacial tyrosine residues, Y356 and Y731, is investigated with a vibronically nonadiabatic theory that treats the transferring proton and all electrons quantum mechanically.
View Article and Find Full Text PDFNanoscale
January 2025
Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing Key Laboratory of Function Materials for Molecule & Structure Construction, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China.
Photocatalytic detoxification of sulfur mustards (, bis (2-chloroethyl) sulfide, SM) is an effective approach for protecting the ecological environment and human health. In order to fabricate COFs with high performance for the selective transformation of the SM simulant 2-chloroethyl ethyl sulfide (CEES) to nontoxic 2-chloroethyl ethyl sulfoxide (CEESO), three porphyrin-based COFs with different donor groups (R = H, OH, and OMe) were synthesized. Among these COFs, COF-OMe, which possesses the strongest electron-donating ability, demonstrated a faster and higher detoxification rate of CEES at various concentrations, achieving selective oxidation of CEES to non-toxic CEESO with 99.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Chemistry and Centre for Processable Electronics, Imperial College London, London, W12 0BZ, UK.
Most current highly efficient organic solar cells utilize small molecules like Y6 and its derivatives as electron acceptors in the photoactive layer. In this work, a small molecule acceptor, SC8-IT4F, is developed through outer side chain engineering on the terminal thiophene of a conjugated 6,12-dihydro-dithienoindeno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IDTT) central core. Compared to the reference molecule C8-IT4F, which lacks outer side chains, SC8-IT4F displays notable differences in molecule geometry (as shown by simulations), thermal behavior, single-crystal packing, and film morphology.
View Article and Find Full Text PDFSmall
January 2025
Department of Materials Science and Engineering, Southern University of Science and Technology (SUSTech), Shenzhen, Guangdong, 518055, China.
Polymeric mixed ionic-electronic conductors (PMIECs) are gaining significant attention due to their potential applications in organic electrochemical transistors (OECTs). However, the performance of n-type OECTs still lags behind that of their p-type counterparts. Here, the structure-performance correlation of fused bithiophene imide dimer (BTI2)-based PMIECs is systematically investigated with the backbone evaluation from acceptor-strong donor (A-SD) to acceptor-donor (A-D), to acceptor-weak donor (A-WD), to acceptor-weak acceptor (A-WA), and finally to A-A structures.
View Article and Find Full Text PDFISME Commun
January 2025
Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China.
Rivers serve important functions for human society and are significantly impacted by anthropogenic nutrient inputs (e.g. organic and sulfur compounds).
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