Vasylevskyi, Serhii I. Kracht, Sonja Corcosa, Paula Fromm, Katharina M. Giese, Bernd Füeg, Michael 2017-01-01 The reduction of Ag⁺ ions to Ag⁰ atoms is a highly endergonic reaction step, only the aggregation to Ag_n clusters leads to an exergonic process. These elementary chemical reactions play a decisive role if Ag nanoparticles (AgNPs) are generated by electron transfer (ET) reactions to Ag⁺ ions. We studied the formation of AgNPs in peptides by photoinduced ET, and in c-cytochromes by ET from their Fe²⁺/hemes. Our earlier photoinduced experiments in peptides had demonstrated that histidine prevents AgNP formation. We have now observed that AgNPs can be easily synthesized with less-efficient Ag⁺-binding amino acids, and the rate increases in the order lysine<asparagine<aspartate<serine. The ability of Fe²⁺/hemes of c- cytochromes to reduce Ag⁺ to AgNPs was studied in an enzymatic experiment and with living bacteria Geobacter sulfurreducens (Gs). application/pdf https://folia.unifr.ch/global/documents/305514 https://folia.unifr.ch/documents/305514/files/vasylevskyi_et_al_2017_formation.pdf https://folia.unifr.ch/documents/305514/files/fro_fsn_sm.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1002/anie.201702621 info:eu-repo/semantics/openAccess License undefined Angewandte Chemie International Edition. - 2017, vol. 56, no. 21, p. 5926-5930 info:eu-repo/classification/udc/57 Formation of silver nanoparticles by electron transfer in peptides and c‐cytochromes http://purl.org/coar/resource_type/c_6501