The mechanism of the hydrolytic kinetic resolution (HKR) of terminal epoxides was investigated by kinetic analysis using reaction calorimetry. The chiral (salen)Co-X complex (X = OAc, OTs, Cl) undergoes irreversible conversion to (salen)Co-OH during the course of the HKR and thus serves as both precatalyst and cocatalyst in a cooperative bimetallic catalytic mechanism. This insight led to the identification of more active catalysts for the HKR of synthetically useful terminal epoxides.

The isotope pairing technique (IPT) is a well‐established 15N method for estimation of denitrification. Presence of anammox, the anaerobic oxidation of NH4+ to N2 with NO2− results in violation of central assumptions on which the IPT is built. It is shown that anammox activity causes overestimation of the N2 production calculated by the IPT. However, experiments with different additions of 15NO3− will reveal the problems posed by anammox. Two alternative calculation procedures are presented, which enable a more accurate quantification of anammox and denitrification activity in sediments where the processes coexist. One procedure is based on measurements of 15N‐N2 production in 15NOx−‐amended intact sediment cores and data addressing the contribution of anammox to total N2 production estimated from slurry incubations. The other procedure is based on measurements of 15N2 production in at least two parallel series of sediment cores incubated with different 15NOx− additions. The calculation procedure presented is used on field data from four studies where the IPT was used and the potential anammox rate measured. The IPT overestimated total 14N‐N2 production rates by 0%, 2.5%, 31%, and 82% relative to the revised estimates from the 4 different sites, where anammox accounted for 0%, 6%, 18%, and 69.8%, respectively, of N2 production. The overestimation of true denitrification was, however, up to several hundred percent. Our analysis suggests however that the IPT does not seriously overestimate N2 production in estuarine sediments because anammox accounts for <6% of N2 production in such sediments, according to present knowledge.

There is a need for quality improvement, as almost 50% of all errors in doses and prescriptions in the medication process were caused by missing actions. We assume that the number of errors could be reduced by simple changes of existing procedures or by implementing automated technologies in the medication process.

Cable bacteria of the family Desulfobulbaceae form centimeter-long filaments comprising thousands of cells. They occur worldwide in the surface of aquatic sediments, where they connect sulfide oxidation with oxygen or nitrate reduction via long-distance electron transport. In the absence of pure cultures, we used single-filament genomics and metagenomics to retrieve draft genomes of 3 marine Candidatus Electrothrix and 1 freshwater Ca. Electronema species. These genomes contain >50% unknown genes but still share their core genomic makeup with sulfate-reducing and sulfur-disproportionating Desulfobulbaceae, with few core genes lost and 212 unique genes (from 197 gene families) conserved among cable bacteria. Last common ancestor analysis indicates gene divergence and lateral gene transfer as equally important origins of these unique genes. With support from metaproteomics of a Ca. Electronema enrichment, the genomes suggest that cable bacteria oxidize sulfide by reversing the canonical sulfate reduction pathway and fix CO2 using the Wood–Ljungdahl pathway. Cable bacteria show limited organotrophic potential, may assimilate smaller organic acids and alcohols, fix N2, and synthesize polyphosphates and polyglucose as storage compounds; several of these traits were confirmed by cell-level experimental analyses. We propose a model for electron flow from sulfide to oxygen that involves periplasmic cytochromes, yet-unidentified conductive periplasmic fibers, and periplasmic oxygen reduction. This model proposes that an active cable bacterium gains energy in the anodic, sulfide-oxidizing cells, whereas cells in the oxic zone flare off electrons through intense cathodic oxygen respiration without energy conservation; this peculiar form of multicellularity seems unparalleled in the microbial world.

Seasonal variation of chlorophyll content, photosynthesis, 0, respiration, and denitrification was measured under light and dark conditions in the sediment of a nutrient-rich Danish lowland stream. Exponential growth of benthic microalgae was observed in early spring (April-May) and photosynthetic capacity persisted until fall. The benthic algae were a major C source for heterotrophic activity as indicated by a close correlation between 0, respiration and Chl content in the sediment. Denitrilication activity was related to Chl content, NO,-availability, and 0, conditions. Diffusion from the overlying water was always the major NO,-source for denitrification. Under lighted conditions, photosynthetic 0, production increased the oxic zone and reduced denitrification activity by up to 85% in spring. A simple diffusion-reaction model allowed denitrification rates to be estimated from 0, respiration rates and concentrations of O2 and N03-in the stream water. Throughout the season, estimated denitrification rates correlated well with those actually measured. The model demonstrated that denitrification activity was controlled primarily by the thickness of the oxic surface layer which served as a diffusion barrier for NO,-to the denitrification zone.