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The anthrax pathogen Bacillus anthracis can remain dormant as spores in soil for many years. This applies to both natural foci and to sites of anthropogenic activity such as tanneries, abattoirs, or wool factories. The A.Br.075 (A-branch) clade (also known as A.Br.Sterne) is prominent not only because it comprises several outbreak strains but even more so because spore preparations of its namesake, the Sterne strain, are counted among the most utilized anthrax animal vaccines. In this study, we genome-sequenced and analyzed 56 additional B. anthracis isolates of the A.Br.075 clade. Four of these we recently retrieved from soil samples taken from a decades-long abandoned tannery. The other 52 strains originated from our archival collection from the 20th century. Notably, the extended phylogeny of the A.Br.075 clade indicated that many of the newly added chromosomes represent basal members, some of which are among the most basal strains from this lineage. Twelve new strains populate a very deep-branching lineage we have named A.Br.Ortho-Sterne (also known as A.Br.076). A further 11 isolates amend the clade named A.Br.Para-Sterne (A.Br.078). Finally, some of the terminal clusters of the clade named A.Br.Eu-Sterne appear to be replete with (near) identical isolates, possibly a result of widespread use of the Sterne vaccine and of its re-isolation from vaccination-related animal anthrax outbreaks. From the accrued new phylogenetic information, we designed and tested a variety of new SNP-PCR assays for rapid and facile genotyping of unassigned B. anthracis genomes. Lastly, the successful isolation of live B. anthracis from a long-abandoned tannery reemphasizes the need for continued risk awareness of such sites. [ABSTRACT FROM AUTHOR]

Soil samples taken during archaeological investigations of a historical tannery area in the eastern suburb of the medieval city of Jena have been investigated by 16S r-RNA gene profiling. The analyses supplied a large spectrum of interesting bacteria, among them Patescibacteria, Methylomirabilota, Asgardarchaeota, Zixibacteria, Sideroxydans and Sulfurifustis. Samples taken from soil inside the residues of large vats show large differences in comparison to the environmental soil. The PCAs for different abundance classes clearly reflect the higher similarity between the bacterial communities of the outside-vat soils in comparison with three of the inside-vat soil communities. Two of the in-side vat soils are distinguishable from the other samples by separate use of each abundance class, but classes of lower abundance are better applicable than the highly abundant bacteria for distinguishing the sampling sites by PCA, in general. This effect could be interpreted by the assumption that less abundant types in the 16S r-RNA data tend to be more related to an earlier state of soil development than the more abundant and might be, therefore, better suited for conclusions on the state of the soils in an earlier local situation. In addition, the analyses allowed identification of specific features of each single sampling site. In one site specifically, DNA hints of animal residue-related bacteria were found. Obviously, the special situation in the in-site vat soils contributes to the diversity of the place, and enhances its Beta-diversity. Very high abundancies of several ammonia-metabolizing and of sulphur compound-oxidizing genera in the metagenomics data can be interpreted as an echo of the former tannery activities using urine and processing keratin-rich animal materials. In summary, it can be concluded that the 16S r-RNA analysis of such archaeological places can supply a lot of data related to ancient human impacts, representing a kind of "ecological memory of soil". [ABSTRACT FROM AUTHOR]

Beside natural factors, human activities are important for the development of microbiomes. Thus, local soil bacterial communities are affected by recent activities such as agriculture, mining and industry. In addition, ancient human impacts dating back centuries or millennia have changed soils and can emboss the recent bacterial communities up to now, representing a certain long-term "memory of soil". Soil samples from five different archaeological excavation places were investigated for the presence of Archaea with a Next Generation Sequencing (NGS) analysis of the DNA coding for 16S r-RNA sequences. It was found that the abundance of Archaea differs strongly between less than one and more than 40 percent of bacteria. A Principal Component Analysis (PCA) of all samples shows that the archaeological excavation places can be distinguished from each other by the archaeal component of soil bacterial communities, which presents a typical pattern for each place. Most samples are marked by the dominance of Crenarchaeota, which are presented mainly by ammonia-related types. High contents of Nanoarchaeaota have been observed in one ash deposit of a historical saline and all samples of a historical tannery area. These samples are also marked by a significant presence of Dadabacteria. The specific abundancies of special Archaea—among them ammonia-oxidizing and sulphur-related types—are due obviously to former human activities and support the concept of the "ecological memory of soil". [ABSTRACT FROM AUTHOR]

Featured Application: The ability of chitosan as a low-cost and environmentally friendly Cr(III) adsorbent was studied to evaluate its potential application in the field of tannery wastewater treatment, in terms of the removal of chromium ions avoiding their conversion into Cr(VI), the compounds of which exert highly toxic and carcinogenic effects on biological systems. Chitosan is very effective in removing metal ions through their adsorption. A preliminary investigation of the adsorption of chromium(III) by chitosan was carried out by means of batch tests as a function of contact time, pH, ion competition, and initial chromium(III) concentration. The rate of adsorption was rather rapid (t1/2 < 18 min) and influenced by the presence of other metal ions. The obtained data were tested using the Langmuir and Freundlich isotherm models and, based on R2 values, the former appeared better applicable than the latter. Chitosan was found to have an excellent loading capacity for chromium(III), namely 138.0 mg Cr per g of chitosan at pH = 3.8, but metal ions adsorption was strongly influenced by the pH. About 76% of the recovered chromium was then removed simply by washing the used chitosan with 0.1 M EDTA (Ethylenediaminetetraacetic acid) solution. This study demonstrates that chitosan has the potential to become an effective and low-cost agent for wastewater treatment (e.g., tannery waste) and in situ environmental remediation. [ABSTRACT FROM AUTHOR]

The tannery industry is one of the economic sectors that contributes to the development of different countries. Globally, Europe and Asia are the main producers of this industry, although Latin America and Africa have been growing considerably in recent years. With this growth, the negative environmental impacts towards different ecosystem resources as a result of the discharges of recalcitrated pollutants, have led to different investigations to generate alternative solutions. Worldwide, different technologies have been studied to address this problem, biological and physicochemical processes have been widely studied, presenting drawbacks with some recalcitrant compounds. This review provides a context on the different existing technologies for the treatment of tannery wastewater, analyzing the physicochemical composition of this liquid waste, the impact it generates on human health and ecosystems and the advances in the different existing technologies, focusing on advanced oxidation processes and the use of microalgae. The coupling of advanced oxidation processes with biological processes, mainly microalgae, is seen as a viable biotechnological strategy, not only for the removal of pollutants, but also to obtain value-added products with potential use in the biorefining of the biomass. [ABSTRACT FROM AUTHOR]