The article presents the results of the study of the hillfort at Bolshie Algashi village (Chuvashia, Russia) conducted in 2016–17. The study provides new data on the cultural and economic dynamics in ...the region during the Bronze and Early Iron Ages. A mixed group of Khula-Syuch and Chirki population can be identified as pastoralists and, probably, also farmers, who developed floodplains and forestless landscapes of the elevated riverbanks. Our research, therefore, provides evidence of almost the oldest farming activity episode in the lower reaches of the Sura River. The Early Iron Age occupation of the site is associated with the Andreevka-Piseraly population, who used the site mostly for its military functions.
Laccases are members of the blue multi‐copper oxidase family that oxidize substrate molecules by accepting electrons at a mononuclear copper centre and transferring them to a trinuclear centre. ...Dioxygen binds to the trinuclear centre and, following the transfer of four electrons, is reduced to two molecules of water. Crystals of the laccase from Cerrena maxima have been obtained and X‐ray data were collected to 1.9 Å resolution using synchrotron radiation. A preliminary analysis shows that the enzyme has the typical laccase structure and several carbohydrate sites have been identified. The carbohydrate chains appear to be involved in stabilization of the intermolecular contacts in the crystal structure, thus promoting the formation of well ordered crystals of the enzyme. Here, the results of an X‐ray crystallographic study on the laccase from the fungus Cerrena maxima are reported. Crystals that diffract well to a resolution of at least 1.9 Å (R factor = 18.953%; Rfree = 23.835; r.m.s.d. bond lengths, 0.06 Å; r.m.s.d. bond angles, 1.07°) have been obtained despite the presence of glycan moieties. The overall spatial organization of C. maxima laccase and the structure of its copper‐containing active centre have been determined by the molecular‐replacement method using the laccase from Trametes versicolor (Piontek et al., 2002) as a structural template. In addition, four glycan‐binding sites were identified and the 1.9 Å X‐ray data were used to determine the previously unknown primary structure of this protein. The identity (calculated from sequence alignment) between the C. maxima laccase and the T. versicolor laccase is about 87%. Tyr196 and Tyr372 show significant extra density at the ortho positions and this has been interpreted in terms of NO2 substituents.
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