Literatuurwetenschap en uitgeverijonderzoek

Over the last few decades cultural sociology and book history have stimulated the study of publishers and their role in the production, distribution, reception and consumption of literature. As such these disciplines have constantly reminded us that literary theory does not study ‘autonomous artefacts’, but texts which are mediated and influenced by various ‘institutions’. But what are the implications? The contributions to this issue of Cahier voor Literatuurwetenschap confront the results of recent and ongoing studies about publishing with the disciplinary idiosyncrasies of general and comparative literature. They not only demonstrate the rich diversity which is typical of this branch of literary studies as far as its method, subject matter and theoretical framework is concerned. They also evaluate acquired ideas and, above all, anticipate new challenges

Probing polyoxometalate-protein interactions using molecular dynamics simulations

The molecular interactions between the Ce(IV)-substituted Keggin anion [PW11O39Ce(OH2)4]3- (CeK) and hen egg white lysozyme (HEWL), was investigated by molecular dynamics (MD) simulations. We compared the analysis of CeK with the Ce(IV)-substituted Keggin dimer [(PW11O39)2Ce]10- (CeK2) and the Zr(IV)-substituted Lindqvist anion [W5O18Zr(OH2)(OH)]3- (ZrL) in order to understand how POM features such as the shape, the size, the charge or the type of incorporated metal ion influence the POM···protein interactions. Simulations revealed two regions of the protein, in which the CeK anion interacts strongly: the cationic sites formed by Arg21 on one hand and by Arg45 and Arg68 on the other. The two sites can be related with the observed selectivity in the hydrolytic cleavage of HEWL. The POMs chiefly interact with the side chains of the positively charged (arginines and lysines) and the polar uncharged (tyrosines, serines and aspargines) residues via electrostatic attraction and hydrogen bonding with the oxygens of the POM framework. The CeK anion shows higher protein affinity than the CeK2 and ZrL anions, because it is less hydrophilic and it has the right size and shape for stablishing interactions with several residues simultaneously. The larger and more negatively charged CeK2 anion has a high solvent-accessible surface, which is sub-optimal for the interaction, while the smaller ZrL anion is highly hydrophilic and it cannot interact simultaneously with several residues so efficiently

Protein-Assisted Formation and Stabilization of Catalytically Active Polyoxometalate Species

International audienceThe effect of the protein environment on the formation and stabilization of an elusive catalytically active polyoxometalate (POM) species, K$_6$[Hf($\alpha_2$-P$_2$W$_{17}$O$_{61}$)] (1), is reported. In the co-crystal of hen egg-white lysozyme (HEWL) with 1, the catalytically active monomeric species is observed, originating from the dimeric 1:2 POM form, while it is intrinsically unstable under physiological pH conditions. The protein-assisted dissociation of the dimeric POM was rationalized by means of DFT calculations. The dissociation process is unfavorable in bulk water, but becomes favorable in the protein–POM complex due to the low dielectric response at the protein surface. The crystal structure shows that the monomeric form is stabilized by electrostatic and water-mediated hydrogen bonding interactions with the protein. It interacts at three distinct sites, close to the aspartate-containing hydrolysis sites, demonstrating high selectivity towards peptide bonds containing this residue