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The key active site residues K185, Y139, D217, D241, D245, and N102 of Thermus thermophilus 3-isopropylmalate dehydrogenase (Tt-IPMDH) have been replaced, one by one, with Ala. A drastic decrease in the kcat value (0.06% compared to that of the wild-type enzyme) has been observed for the K185A and D241A mutants. Similarly, the catalytic interactions (Km values) of these two mutants with the substrate IPM are weakened by more than 1 order of magnitude. The other mutants retained some (1-13%) of the catalytic activity of the wild-type enzyme and do not exhibit appreciable changes in the substrate Km values. The pH dependence of the wild-type enzyme activity (pK = 7.4) is shifted toward higher values for mutants K185A and D241A (pK values of 8.4 and 8.5, respectively). For the other mutants, smaller changes have been observed. Consequently, K185 and D241 may constitute a proton relay system that can assist in the abstraction of a proton from the OH group of IPM during catalysis. Molecular dynamics simulations provide strong support for the neutral character of K185 in the resting state of the enzyme, which implies that K185 abstracts the proton from the substrate and D241 assists the process via electrostatic interactions with K185. Quantum mechanics/molecular mechanics calculations revealed a significant increase in the activation energy of the hydride transfer of the redox step for both D217A and D241A mutants. Crystal structure analysis of the molecular contacts of the investigated residues in the enzyme-substrate complex revealed their additional importance (in particular that of K185, D217, and D241) in stabilizing the domain-closed active conformation. In accordance with this, small-angle X-ray scattering measurements indicated the complete absence of domain closure in the cases of D217A and D241A mutants, while only partial domain closure could be detected for the other mutants. This suggests that the same residues that are important for catalysis are also essential for inducing domain closure.

Bannucine is an Aspidosperma alkaloid isolated from the dried leaves of Catharanthus roseus. The molecule is a derivative of vindoline bearing a C10 substituent, a pattern common to the antineoplastic dimeric indole alkaloids of C. roseus. In bannucine, a 2-pyrrolidone moiety is attached at C5′ to the aromatic ring of the vindoline core at C10. In the present work we report the synthesis of bannucine and its 5′-epimer from natural (−)-vindoline using a cyclic N-acyliminium ion intermediate whose N-acylaminocarbinol precursor is synthesized by the partial reduction of succinimide. We also describe the separation and the structural analysis of the two epimers, using among others, single crystal X-ray diffraction methods, in order to clarify the orientation of the proton attached to the C5′ carbon. The in vitro antineoplastic activity of the pure epimers was also investigated, but none of the two substances showed significant activity on the examined tumour cell lines.

Dehydroascorbate reductase (DHAR) catalyzes the glutathione (GSH)-dependent reduction of dehydroascorbate and plays a direct role in regenerating ascorbic acid, an essential plant antioxidant vital for defense against oxidative stress. DHAR enzymes bear close structural homology to the glutathione transferase (GST) superfamily of enzymes and contain the same active site motif, but most GSTs do not exhibit DHAR activity. The presence of a cysteine at the active site is essential for the catalytic functioning of DHAR, as mutation of this cysteine abolishes the activity. Here we present the crystal structure of DHAR2 from Arabidopsis thaliana with GSH bound to the catalytic cysteine. This structure reveals localized conformational differences around the active site which distinguishes the GSH-bound DHAR2 structure from that of DHAR1. We also unraveled the enzymatic step in which DHAR releases oxidized glutathione (GSSG). To consolidate our structural and kinetic findings, we investigated potential conformational flexibility in DHAR2 by normal mode analysis and found that subdomain mobility could be linked to GSH binding or GSSG release.

The mutant E270A of Thermus thermophilus 3-isopropylmalate dehydrogenase exhibits largely reduced (∼1%) catalytic activity and negligible activation by K(+) compared to the wild-type enzyme. A 3-4 kcal/mol increase in the activation energy of the catalysed reaction upon this mutation could also be predicted by QM/MM calculations. In the X-ray structure of the E270A mutant a water molecule was observed to take the place of K(+). SAXS and FRET experiments revealed the essential role of E270 in stabilisation of the active domain-closed conformation of the enzyme. In addition, E270 seems to position K(+) into close proximity of the nicotinamide ring of NAD(+) and the electron-withdrawing effect of K(+) may help to polarise the aromatic ring in order to aid the hydride-transfer.

The three-dimensional structure of the enzyme 3-isopropylmalate dehydrogenase from the bacterium Thermus thermophilus in complex with Mn2+, its substrate isopropylmalate and its co-factor product NADH at 2.0 A resolution features a fully closed conformation of the enzyme. Upon closure of the two domains, the substrate and the co-factor are brought into precise relative orientation and close proximity, with a distance between the C2 atom of the substrate and the C4N atom of the pyridine ring of the co-factor of approximately 3.0 A. The structure further shows binding of a K+ ion close to the active site, and provides an explanation for its known activating effect. Hence, this structure is an excellent mimic for the enzymatically competent complex. Using high-level QM/MM calculations, it may be demonstrated that, in the observed arrangement of the reactants, transfer of a hydride from the C2 atom of 3-isopropylmalate to the C4N atom of the pyridine ring of NAD+ is easily possible, with an activation energy of approximately 15 kcal·mol−1. The activation energy increases by approximately 4–6 kcal·mol−1 when the K+ ion is omitted from the calculations. In the most plausible scenario, prior to hydride transfer the e-amino group of Lys185 acts as a general base in the reaction, aiding the deprotonation reaction of 3-isopropylmalate prior to hydride transfer by employing a low-barrier proton shuttle mechanism involving a water molecule. Database Structural data have been submitted to the Protein Data Bank under accession number 4F7I.

A new copper-catalyzed oxidative ring closure of ethynyl anilides with diaryliodonium salts was developed for the highly modular construction of benzoxazines bearing a fully substituted exo double bond. The oxidative transformation includes an unusual 6-exo-dig cyclization step with the formation of C-O and C-C bonds.

Synthesis, structure determination and in vitro antiproliferative assay of a series of novel ferrocenenyl hydrazones containing 4-halopyridazin-3(2H)-one fragment(s) and three representative N-aryl-substituted (S-p)-ferroceno[d]pyridazinones are presented. The model compounds can be considered as different assemblies of the potential binding sites capable of establishing interactions including hydrogen bonds and pi-pi interactions with the relevant residues of biomolecules. Their in vitro antiproliferative effect was investigated against four tumorous cell lines by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-assay. Our data indicate that bis-hydrazone of 1,1'-diformylferrocene carrying N-benzyl substituents and a chloropyridazinyl-substituted ferroceno[d]pyridazinone display significant activity on each cell lines investigated. The efficiency of the latter drug candidate and one N-benzyl mono-hydrazone on A2870 cell line is comparable to that of cisplatin. The constitution and relative configuration of the model compounds were established by H-1, C-13 and N-15 NMR methods. The structures of a mono-and bis-ferrocenylhydrazone containing 4-bromopyridazinone unit(s) were confirmed by single crystal X-ray diffraction. (C) 2013 Elsevier B.V. All rights reserved.

This chapter describes the impact of Lysenkoism in Hungary in terms of three topics and three stages. The topics we cover are the controversy’s effect upon the institutionalization of biology in postwar Hungary, the five strategies of response exhibited by Hungarian biologists, and Lysenko’s personal contribution to the demise of his theories in Hungary. The three historical stages these three topics are examined across are the reception to Lysenko’s theories in Hungary prior to the Cold War, the imposition of Lysenko’s theories upon Hungarian biology once the Cold War was underway, and the counter-reception to Lysenkoism, beginning in 1953.

In many established methods, identification of hydrogen bonds (H-bonds) is primarily based on pairwise comparison of distances between atoms. These methods often give rise to systematic errors when sulfur is involved. A more accurate method is the non-covalent interaction index, which determines the strength of the H-bonds based on the associated electron density and its gradient. We applied the NCI index on the active site of a single-cysteine peroxiredoxin. We found a different sulfur hydrogen-bonding network to that typically found by established methods and we propose a more accurate equation for determining sulfur H-bonds based on geometrical criteria. This new algorithm will be implemented in the next release of the widely-used CHARMM program (version 41b) and will be particularly useful for analyzing water molecule-mediated H-bonds involving different atom types. Furthermore, based on the identification of the weakest sulfur-water H-bond, the location of hydrogen peroxide for the nucleophilic attack by the cysteine sulfur can be predicted. In general, current methods to determine H-bonds will need to be reevaluated, thereby leading to better understanding of the catalytic mechanisms in which sulfur chemistry is involved.

After Heitler and London published their pioneering work on the application of quantum mechanics to chemistry in 1927, it became an almost unquestioned dogma that chemistry would soon disappear as a discipline of its own rights. Reductionism felt victorious in the hope of analytically describing the chemical bond and the structure of molecules. The old quantum theory has already produced a widely applied model for the structure of atoms and the explanation of the periodic system. This paper will show two examples of the entry of quantum physics into more classical fields of chemistry: inorganic chemistry and physical chemistry. Due to their professional networking, George Hevesy and Michael Polanyi found their ways to Niels Bohr and Fritz London, respectively, to cooperate in solving together some problems of classical chemistry. Their works on rare earth elements and adsorption theory throws light to the application of quantum physics outside the reductionist areas. They support the heuristic and persuasive value of quantum thinking in the 1920–1930s. Looking at Polanyi’s later oeuvre, his experience with adsorption theory could be a starting point of his non-justificationist philosophy.

Acylaminoacyl peptidase from Aeropyrum pernix is a homodimer that belongs to the prolyl oligopeptidase family. The monomer subunit is composed of one hydrolase and one propeller domain. Previous crystal structure determinations revealed that the propeller domain obstructed the access of substrate to the active site of both subunits. Here we investigated the structure and the kinetics of two mutant enzymes in which the aspartic acid of the catalytic triad was changed to alanine or asparagine. Using different substrates, we have determined the pH dependence of specificity rate constants, the rate-limiting step of catalysis, and the binding of substrates and inhibitors. The catalysis considerably depended both on the kind of mutation and on the nature of the substrate. The results were interpreted in terms of alterations in the position of the catalytic histidine side chain as demonstrated with crystal structure determination of the native and two mutant structures (D524N and D524A). Unexpectedly, in the homodimeric structures, only one subunit displayed the closed form of the enzyme. The other subunit exhibited an open gate to the catalytic site, thus revealing the structural basis that controls the oligopeptidase activity. The open form of the native enzyme displayed the catalytic triad in a distorted, inactive state. The mutations affected the closed, active form of the enzyme, disrupting its catalytic triad. We concluded that the two forms are at equilibrium and the substrates bind by the conformational selection mechanism.

C1r is a modular serine protease which is the autoactivating component of the C1 complex of the classical pathway of the complement system. We have determined the first crystal structure of the entire active catalytic region of human C1r. This fragment contains the C-terminal serine protease (SP) domain and the preceding two complement control protein (CCP) modules. The activated CCP1–CCP2–SP fragment makes up a dimer in a head-to-tail fashion similarly to the previously characterized zymogen. The present structure shows an increased number of stabilizing interactions. Moreover, in the crystal lattice there is an enzyme–product relationship between the C1r molecules of neighboring dimers. This enzyme–product complex exhibits the crucial S1–P1 salt bridge between Asp631 and Arg446 residues, and intermolecular interaction between the CCP2 module and the SP domain. Based on these novel structural information we propose a new split-and-reassembly model for the autoactivation of the C1r. This model is consistent with experimental results that have not been explained adequately by previous models. It allows autoactivation of C1r without large-scale, directed movement of C1q arms. The model is concordant with the stability of the C1 complex during activation of the next complement components.

This chapter reflects upon the experiences of the author who witnessed the emergence of the field of history of science in 1970s Hungary. Based partly on research and partly on his own memories and the correspondence from his private archive, Pallo argues that in Hungary behind the Iron Curtain there was not much room for independent science policy. The branches of STS, including history of science, worked in isolation from each other and from the Western tendencies. The intellectual and sociological situation of history of science in Hungary is explained in this framework of “isolation.” Isolation dominated the activity of researchers inside their scientific community and in their virtually nonexistent relationships with their compatriots living in the West, particularly in Britain, such as Polanyi, Lakatos, and Koestler. Under these circumstances the reception of Kuhn’s Structure of Scientific Revolution remained to the philosophers.

The inhibitory γ-aminobutyric acid transporter subtype 1 (GAT1) maintains low resting synaptic GABA level, and is a potential target for antiepileptic drugs. Here we report a high scored binding mode that associates GABA with gating in a homology model of the human GAT1. Docking and molecular dynamics calculations recognize the amino function of GABA in the H-bonding state favoring TM1 and TM8 helix residues Y60 and S396, respectively. This ligand binding mode visibly ensures the passage of GABA and substrate inhibitors (R)-homo-β-Pro, (R)-nipecotic acid, and guvacine. It might therefore represent the principle, sufficient for sorting out less-effective or non-GAT ligands such as β-Pro, (S)-nipecotic acid, (R)-baclofen, Glu, and Leu.

Textbooks and encyclopedias represent different genres of scientific literature. Textbooks help the students to prepare for their examinations in various subjects taught at schools, such as logic, metaphysic, chemistry. In the 17th Century some Calvinist professors, mostly in Germany, thought that a universal wholeness should be taught for the students. Encyclopedias adequately expressed this vision. Some of these professors, including Johannes Alsted, were invited to Hungary, Transylvania, to introduce the encyclopedic spirit to the local schools. This act fostered the first textbook in Hungarian language written by Janos Apaczai Csere. This book was an encyclopedia born mostly in the Netherlands where the author studied. The Cartesian philosophy combined with a Ramist system served as the basis of the book. Its history shows how the local conditions influence the content of knowledge incorporated into a textbook.

Comparing with the population, many Hungarians achieved outstanding success in natural sciences in the 20th century. From this fact, the conclusion can be drawn that Hungarians are very creative. In analyzing this conclusion, a simple general model of creativity is used which distinguishes between the approaches of the genious theory and Zeitgeist theory. By applying the Zeitgeist theory, the paper concludes that some elements of the Hungarian culture significantly contributed to the success of the Hungarian scientists, although all of them left Hungary at a certain point of their career. Migration was a key element of their success because they could find relevant problems and meritocratic scientific community in the scientific centers.

The impact of radical political changes had a surprisingly strong impact upon the universities in Hungary. In the twentieth century, Hungary was part of two empires (the Habsburg and the Soviet empires), suffered from two World Wars, lived under two totalitarian regimes (communism twice, Nazism once), and experienced several revolutions. One would expect that universities would provide asylums, hiding places for professionals to defend themselves in such stormy atmosphere. In fact, however, the universities proved to be one of the first points to which political changes were extended. Besides showing data about the political influences on the number of universities, personnel, and curricula, this paper intends to provide an analysis of this transition, and illustrate the mechanism of change on the basis of the Technical University of Budapest, focusing on the period of 1945–1953. This is the period of the introduction of the Soviet university model to replace the traditional German one. The paper aims to prove that the myth of expertise does not shield universities from political intrusion but it helps to make the intrusion somewhat endurable.

A new copper-catalyzed oxidative ring closure of ethynyl anilides with diaryliodonium salts is developed for the highly modular construction of benzoxazines bearing a fully substituted exo double bond.

Entering the final phase of the preparation for negotiations on EU accession, the main area of work of our department is the co-ordination of the adaptation of European legislation in the Hungarian agricultural and foodstuffs sectors. Our specific field is the assessment of the EU's horizontal and vertical foodstuffs quality provisions, and the elaboration of their possible application in Hungary. This paper focuses particularly on the scientific analysis of the adoption of EC provisions regarding speciality products that are of high importance from the point of view of the exportability of Hungarian foodstuffs.

This chapter approaches various occurrences of scientific nationalism in nineteenth-century Hungary; the term ‘scientific nationalism’ stands for both nationalism occurring within science and nationalism based on science. The latter form of nationalism, which used science directly for political purposes as an argument and justification for nationalist politics, had gradually become a widespread ideology in Hungary in the second part of the nineteenth century. It was not science, but politics, that was nationalist; however, science could not stay neutral on this central political issue. It developed a national character manifested both in its institutional structure and in its cognitive contents.

In the early history of surface chemistry, in the 1920s, the nature of gas adsorption was a pivotal subject. A theory created by Michael Polanyi in the peripheral Hungary contradicted the received view originating from the American Irving Langmuir. When working out his theory, Polanyi had not even heard of Langmuir's rival description. However, Polanyi emigrated from Hungary to Germany, the centre of his field, and tried to defend his adsorption theory in the circle of the leading experts, including Einstein and Fritz Haber. This controversy seemed vital to his survival as a scientist and as an immigrant. The aim of this article is to recapitulate this controversy, with its sad undercurrents, the role of local science, methods of argumentation, and the work of a central scientific community.

Ambient level of gamma -aminobutyric acid (GABA), the major inhibitory neurotransmitter of the brain is mediated by neuronal and glial GABA transporters (GATs), members of the sodium and chloride ion-dependent solute carrier family. The neuronal GABA transporter subtype (GAT-1) has already been proven to be the target for the antiepileptic drug Tiagabine. However, druggability of glial GAT-2 and GAT-3 is yet to be established. Recent advances in structure elucidation of a bacterial orthologue leucine transporter in complex with different substrates substantiate homology modeling of human GATs (hGATs). These modeling studies can provide mechanistic clues for structure-based prediction of the potential of medicinal chemistry campaigns. A recently identified characteristic structural feature of the occluded conformation of hGATs is that similar extra- and intracellular gates are formed by middle-broken transmembrane helices TM1 and TM6. Binding crevice formed by unwound segments of broken helices facilitates symport of GABA with Na+ ion via fitting of GABA to TM1-bound Na+ closely inside. Favored accommodation of substrate inhibitors with high docking score predicts efficient inhibition of the neuronal hGAT-1 if the TM1-TM8 binding prerequisite for GABA was used. Docking, molecular dynamics and transport data indicate, that amino acids participating in substrate binding of the neuronal hGAT-1 and the glial hGAT-2 and hGAT-3 subtypes are different. By contrast, substrate binding crevices of hGAT-2 and hGAT-3 cannot be distinguished, avoiding sensible prediction of efficient selective substrate inhibitors. Glial subtypes might be specifically distinguished by interfering Zn2+ binding in the second extracellular loop of hGAT-3. Formation of the unique ring-like Na+-GABA complex in the occluded binding crevices anticipates family member symporters exploring chemiosmotic energy via reversible chemical coupling of Na+ ion.

Crystal structures of transmembrane transport proteins belonging to the important families of neurotransmitter-sodium symporters reveal how they transport neurotransmitters across membranes. Substrate-induced structural conformations of gated neurotransmitter-sodium symporters have been in the focus of research, however, a key question concerning the mechanism of Na(+) ion coupling remained unanswered. Homology models of human glial transporter subtypes of the major inhibitory neurotransmitter gamma-aminobutyric acid were built. In accordance with selectivity data for subtype 2 vs. 3, docking and molecular dynamics calculations suggest similar orthosteric substrate (inhibitor) conformations and binding crevices but distinguishable allosteric Zn(2+) ion binding motifs. Considering the occluded conformational states of glial human gamma-aminobutyric acid transporter subtypes, we found major semi-extended and minor ring-like conformations of zwitterionic gamma-aminobutyric acid in complex with Na(+) ion. The existence of the minor ring-like conformation of gamma-aminobutyric acid in complex with Na(+) ion may be attributed to the strengthening of the intramolecular H-bond by the electrostatic effect of Na(+) ion. Coupling substrate uptake into cells with the thermodynamically favorable Na(+) ion movement through substrate-Na(+) ion complex formation may be a mechanistic principle featuring transmembrane neurotransmitter-sodium symporter proteins.

This paper presents a framework for the study of George Hevesy's research in the 1910s by distinguishing two styles of radioactivity research: the analytical (as practices in Manchester and Vienna in some extent) and the natural historical styles (as practiced in Hungary). Georg Hevesy's approach combined the two types. Indeed, by studying Hevesy's research in context, I show that the earliest applications of isotopes were born in parallel with the establishment of the isotope theory of matter.

Ligand-bound and free structures of brain membrane targets for L-glutamate (Glu) suggest the view, that quaternary rearrangements are associated with ligand binding. Rearrangement of the machinery of the signaling apparatus, such as molecular switches, recognition sites and the target structures for ligand binding of Glu-operated ion channel and heptahelical G-protein-coupled family receptors have been quantified and compared with the use of the root mean square (RMS) values. In addition to conformational rearrangement of the Glu receptor structures in complex with a series of ligands, conformations of Glu in various target structures became available. High resolution data revealed that the extended Glu conformation is conserved in the binding crevice of all ionotropic Glu receptors (iGluRs). Furthermore, the extended conformations of Glu that characterize iGluRs and mGluRs are distinguishable by distance and torsion angle parameters, such as deltaC1-C2 and Calpha-Cbeta-Cgamma-C2. By contrast, a bent Glu conformation is recognized in Glu transporters.

It is widely accepted that the catalytic activity of serine proteases depends primarily on the Asp-His-Ser catalytic triad and other residues within the vicinity of this motif. Some of these residues form the oxyanion binding site that stabilizes the tetrahedral intermediate by hydrogen bonding to the negatively charged oxyanion. In acylaminoacyl peptidase from the thermophile Aeropyrum pernix, the main chain NH group of Gly369 is one of the hydrogen bond donors forming the oxyanion binding site. The side chain of His367, a conserved residue in acylaminoacyl peptidases across all species, fastens the loop holding Gly369. Determination of the crystal structure of the H367A mutant revealed that this loop, including Gly369, moves away considerably, accounting for the observed three orders of magnitude decrease in the specificity rate constant. For the wild-type enzyme ln(k(cat)/K(m)) vs. 1/T deviates from linearity indicating greater rate enhancement with increasing temperature for the dissociation of the enzyme-substrate complex compared with its decomposition to product. In contrast, the H367A variant provided a linear Arrhenius plot, and its reaction was associated with unfavourable entropy of activation. These results show that a residue relatively distant from the active site can significantly affect the catalytic activity of acylaminoacyl peptidase without changing the overall structure of the enzyme.

A természettudományok, a technika és az orvoslás tárgyi, képi és írott forrásai (az 1997. évi ankét anyaga). Tanulmányok a természettudományok, a technika és az orvoslás történetéből = Studies into the History of Science, Technology and Medicine

A mérnök, a természettudós és az orvos szerepe a társadalomban (az 1995. évi ankét anyaga). Tanulmányok a természettudományok, a technika és az orvoslás történetéből = Studies into the History of Science, Technology and Medicine

A magyar műszaki-, természet- és orvostudományok kommunikációs formái (Az 1993. évi ankét anyaga). Műszaki, természettudományos és orvosi gyűjtők és gyűjtemények (Az 1994. évi ankét anyaga). Tanulmányok a természettudományok, a technika és az orvoslás történetéből = Studies into the History of Science, Technology and Medicine

Tanulmányok a természettudományok, a technika és az orvoslás történetéből. Tanulmányok a természettudományok, a technika és az orvoslás történetéből = Studies into the History of Science, Technology and Medicine

According to a joke circulating among American scientists around the time of the Second World War, some physicists were discussing the chances of a possible visit to Earth by extraterrestrial beings armed with superior intelligence. One of the physicists, perhaps Enrico Fermi, remarked that the aliens were already among them but they called themselves Hungarians. This joke inspired the title of Istvan Hargittai's book The Martians of Science: Five Physicists who Changed the Twentieth Century, in which, like a modern-day Plutarch, he relates the parallel biographies of five Hungarian scientists who emigrated to the US and played major roles in science and the development of the atomic bomb.

The UV absorption of KCl crystals grown at different rates from aqueous solutions containing SnCl2 and PbCl2 in various concentrations was investigated as a function of the concentration of dopants built-in into the crystal. With increasing dopant concentration characteristic changes were observed in the absorption spectra at about 10−2 mole% concentration in the case of the non-isomorphic Sn dopant, and at 2×10−1 mole% in the case of the isomorphic Pb. The changes indicate that the manner in which the dopants are incorporated into and distributed within the crystal differs from that at lower dopant concentrations.

This essay deals with an issue that has never before been the focus of attention in the field of research on the history of chemistry in Italy: the diffusion of Mendeleev’s periodic system in our nation. In the following text we will analyze the situation in the period preceding the arrival of Mendeleev’s theory in Italy with regard to the matter of classifying elements. By doing so, it will be possible to demonstrate that—despite the superficiality and lack of accuracy of certain studies—Italian chemistry was already very willing to consider new proposals relating to the classification of elements. We will then attempt to illustrate how Mendeleev’s work not only attracted the attention of the most renowned Italian chemists, such as Augusto Piccini and Giacomo Ciamician, but also became widely used in university texts and secondary school textbooks. In order to understand the classification criteria for elements adopted by Italian chemists before Mendeleev and therefore the cultural terrain the law of periodicity was to take root in, it would be better to refer to a number of texts used widely for teaching in universities. We will examine four of these, published between 1819 and 1867. In all these texts, the term “simple bodies” appears, with the expression “simple substances” used less frequently, while Antoine-Laurent Lavoisier (1743–94), in his 1789 Traité élémentaire de chimie (Traité thereafter), uses the same term “simple substances” or “simple substances … which may be considered as the elements of bodies.” It is interesting to note that Vincenzo Dandolo’s Italian translation (first edition 1792) uses the expression “sostanze semplici,” interpreting quite literally the Frenchman’s choice of term. Thirty years after publication of the Traité, Antonio Santagata (1774–1858), professor of general chemistry at the Pontificia Università di Bologna, published his Lezioni di chimica elementare [Lessons in elementary chemistry], derived from Lezioni di chimica elementare: applicata alla medicina e alle arti [Lessons in Elementary Chemistry: Applied to Medicine and the Arts] (Bologna, 1804), written by his predecessor in the university chair, Pellegrino Salvigni (1777–1841).