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AbstractSerine proteases are a family of enzymes that degrade a wide range of proteins and play vital roles in a variety of biological processes. Their mechanism of action involves several catalytic strategies that are common in enzymatic catalysis. In this article, we review the catalytic mechanism of serine proteases and how it was elucidated ove...
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Lipoic acid is an essential cofactor in cellular catabolism, such as in the oxidative decarboxylation of pyruvate and of α-ketoglutarate in the mitochondrial matrix of eukaryotes and the cytoplasm of prokaryotes. Today, lipoic acid is marketed as an ingredient in dietary supplements, in sports nutrition, anti-aging remedies and in drugs to treat di...
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This contribution gives a detailed account of the element predictions Dmitri Ivanovich Mendeleev made after setting up the periodic table of the elements in 1869, with a special focus on those that turned out to be unsuccessful. It is argued that most of these instances are connected to a general inability to place the rare earth metals correctly i...
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The notion of activity is of a purely thermodynamic nature. It is intimately linked to the law of mass action and more generally to that of equilibrium constant. It was conceived and introduced in the realm of chemistry at the beginning of twentieth century by Lewis (Proc Am Acad Arts Sci 37:49‒69, 1901; Proc Am Acad Arts Sci 43:259‒293, 1907; J Am...
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After a historical excursus, the basic properties of tungsten are summarized, followed by selected classes of inorganic compounds (tungsten halides and oxyhalides, tungsten oxides, Magnéli phases and tungsten bronzes, iso- and heteropolyoxotungstates). Subsequently, the specifics of non-sag tungsten wire as well as tungsten carbide and a variety of...
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AbstractA handy diagram—the Raman parameter information diagram, or “RAPID”—is proposed here, which can be used for listing spectral parameters associated with a Raman spectrum. It is demonstrated how, by drawing simple shapes such as lines and triangles, it becomes possible to easily express various findings in a Raman spectrum, for example red- (...
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High-pressure gas chromatography is not a novel concept, but it is an intriguing one: the eco-friendly chimera seeks to combine the advantages of GC and HPLC, which has led to the development of supercritical fluid chromatography (SFC). But while the chromatographic age of supercritical fluids has been advertised by proponents and manufacturers for...
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This lecture text demonstrates how the mineral lorandite is used as a detector of solar neutrinos. Because the age of the lorandite deposit in Allchar, North Macedonia, is known, this opened the possibility to determine the solar neutrino flux over the last 4.3 million years.
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Obtaining an essential oil from the lily-of-the-valley (Convallaria majalis L.) that embodies the characteristic smell of the living flowers is not possible even today. Challenged by this pitfall, organic chemists and perfumers have generated a wealth of artificial compounds over the last 120 years, which confer fresh, green, flowery, crisp, aldehy...
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Nucleophilic substitution in electron-deficient arenes is one of the fundamental processes in organic chemistry; however, its mechanism as presented in textbooks does not adequately describe the process. According to this generally accepted mechanism, it is limited to substitution of halogens via nucleophilic addition at positions occupied by halog...
