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The recent trend of literary tattoos, particularly popular in the Englishspeaking world, represents a new way of disseminating writers’ portraits, emblematic motifs, and textual fragments, on the body and online. Laurence Sterne’s already highly visual, highly quotable work is no exception. Based on a surprising encounter, this essay takes its cue from Tristram Shandy as an aesthetic object and explores how human skin can read like a blank page on which to reinscribe Sternean ink and its endless mobility. [ABSTRACT FROM AUTHOR]

This article explores how the notion of mobility resonates with visual responses to Sterne's fiction (1996-2016). With a specific focus on migration patterns of the Sterne/Tristram/Yorick triad, it is argued that artists have created, in a variety of media, a body of visual Sterneana characterised by embedded imaginary spaces and multiple interpretative frames through a fluctuating proximity with the text and the enduring ubiquity of eighteenth-century images in the form of graphic afterlives. Emblematic motifs and isolated fragments, as well as circulation in cyberspace, also raise the issue of how the word and image relationship is continuously reconfigured. [ABSTRACT FROM AUTHOR]

The Mre11-Rad50-Nbs1 ( MRN) complex is a central factor in the repair of DNA double-strand breaks ( DSBs). The ATP-dependent mechanisms of how MRN detects and endonucleolytically processes DNA ends for the repair by microhomology-mediated end-joining or further resection in homologous recombination are still unclear. Here, we report the crystal structures of the ATPγS-bound dimer of the Rad50 NBD (nucleotide-binding domain) from the thermophilic eukaryote Chaetomium thermophilum ( Ct) in complex with either DNA or CtMre11 RBD (Rad50-binding domain) along with small-angle X-ray scattering and cross-linking studies. The structure and DNA binding motifs were validated by DNA binding experiments in vitro and mutational analyses in Saccharomyces cerevisiae in vivo. Our analyses provide a structural framework for the architecture of the eukaryotic Mre11-Rad50 complex. They show that a Rad50 dimer binds approximately 18 base pairs of DNA along the dimer interface in an ATP-dependent fashion or bridges two DNA ends with a preference for 3′ overhangs. Finally, our results may provide a general framework for the interaction of ABC ATPase domains of the Rad50/ SMC/RecN protein family with DNA. [ABSTRACT FROM AUTHOR]

Fatty acids are among the major building blocks of living cells, making lipid biosynthesis a potent target for compounds with antibiotic or antineoplastic properties. We present the crystal structure of the 2.6-MDa Saccharomyces cerevisiae fatty acid synthase (FAS) multienzyme in complex with the antibiotic cerulenin, representing, to our knowledge, the first structure of an inhibited fatty acid megasynthase. Cerulenin attacks the FAS ketoacyl synthase (KS) domain, forming a covalent bond to the active site cysteine C1305. The inhibitor binding causes two significant conformational changes of the enzyme. First, phenylalanine F1646, shielding the active site, flips and allows access to the nucleophilic cysteine. Second, methionine M1251, placed in the center of the acyl-binding tunnel, rotates and unlocks the inner part of the fatty acid binding cavity. The importance of the rotational movement of the gatekeeping M1251 side chain is reflected by the cerulenin resistance and the changed product spectrum reported for S. cerevisiae strains mutated in the adjacent glycine G1250. Platensimycin and thiolactomycin are two other potent inhibitors of KSs. However, in contrast to cerulenin, they show selectivity toward the prokaryotic FAS system. Because the flipped F1646 characterizes the catalytic state accessible for platensimycin and thiolactomycin binding, we superimposed structures of inhibited bacterial enzymes onto the S. cerevisiae FAS model. Although almost all side chains involved in inhibitor binding are conserved in the FAS multienzyme, a different conformation of the loop K1413-K1423 of the KS domain might explain the observed low antifungal properties of platensimycin and thiolactomycin. [ABSTRACT FROM AUTHOR]

Examines the structure of the active center in dark-adapted bacteriorhodopsin using nuclear magnetic resonance spectroscopy. Forms of bacteriorhodopsin present in the dark-adapted state; Determination of the wavelength of chromophore absorption through the specific amino acid composition in the active center; Conversion of light energy into a proton gradient.