Life Science 2.0: reframing the life science sector for 'the benefit on mankind'.

The COVID-19 pandemic put the life science sector to the test. Vaccines were developed at unprecedented speed, benefiting from decades of fundamental research and now honoured by a Nobel Prize. However, we saw that the fruits of science were inequitably distributed. Most low- and middle-income countries were left behind, deepening the inequalities that the Sustainable Development Goals were set to reduce. We argue that the life science sector must reinvent itself to be better and more equitably prepared for the next health crisis and to ensure fair access to health across current and future generations. Our recommendations include global governance, national strategies and the role of universities and corporations. Improved and more equitable health care should be centre stage for global health action and a core mission of a reframed Life Science sector - what we call Life Science 2.0.Paper ContextMain findings: During the COVID-19 pandemic the Life Science sector stepped up to the challenge, but vaccines and medicines were not equitably distributed.Added knowledge: Obstacles were identified that hindered global access to medical innovations.Global health impact for policy and action: Global and national governance, universities and the private sector should join forces to create a Life Science sector (Life Science 2.0) that affords equitable access to medical advances across geographical and generational boundaries and socio-economic strata.

Identification of a novel compound that simultaneously impairs the ubiquitin-proteasome system and autophagy.

The ubiquitin-proteasome system (UPS) and macroautophagy/autophagy are the main proteolytic systems in eukaryotic cells for preserving protein homeostasis, i.e., proteostasis. By facilitating the timely destruction of aberrant proteins, these complementary pathways keep the intracellular environment free of inherently toxic protein aggregates. Chemical interference with the UPS or autophagy has emerged as a viable strategy for therapeutically targeting malignant cells which, owing to their hyperactive state, heavily rely on the sanitizing activity of these proteolytic systems. Here, we report on the discovery of CBK79, a novel compound that impairs both protein degradation by the UPS and autophagy. While CBK79 was identified in a high-content screen for drug-like molecules that inhibit the UPS, subsequent analysis revealed that this compound also compromises autophagic degradation of long-lived proteins. We show that CBK79 induces non-canonical lipidation of MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 beta) that requires ATG16L1 but is independent of the ULK1 (unc-51 like autophagy activating kinase 1) and class III phosphatidylinositol 3-kinase (PtdIns3K) complexes. Thermal preconditioning of cells prevented CBK79-induced UPS impairment but failed to restore autophagy, indicating that activation of stress responses does not allow cells to bypass the inhibitory effect of CBK79 on autophagy. The identification of a small molecule that simultaneously impairs the two main proteolytic systems for protein quality control provides a starting point for the development of a novel class of proteostasis-targeting drugs.

A FabG inhibitor targeting an allosteric binding site inhibits several orthologs from Gram-negative ESKAPE pathogens.

The spread of antibiotic resistance within the ESKAPE group of human pathogenic bacteria poses severe challenges in the treatment of infections and maintenance of safe hospital environments. This motivates efforts to validate novel target proteins within these species that could be pursued as potential targets for antibiotic development. Genetic data suggest that the enzyme FabG, which is part of the bacterial fatty acid biosynthetic system FAS-II, is essential in several ESKAPE pathogens. FabG catalyzes the NADPH dependent reduction of 3-keto-acyl-ACP during fatty acid elongation, thus enabling lipid supply for production and maintenance of the cell envelope. Here we report on small-molecule screening on the FabG enzymes from A. baumannii and S. typhimurium to identify a set of µM inhibitors, with the most potent representative (1) demonstrating activity against six FabG-orthologues. A co-crystal structure with FabG from A. baumannii (PDB:6T65) confirms inhibitor binding at an allosteric site located in the subunit interface, as previously demonstrated for other sub-µM inhibitors of FabG from P. aeruginosa. We show that inhibitor binding distorts the oligomerization interface in the FabG tetramer and displaces crucial residues involved in the interaction with the co-substrate NADPH. These observations suggest a conserved allosteric site across the FabG family, which can be potentially targeted for interference with fatty acid biosynthesis in clinically relevant ESKAPE pathogens.

In Situ Target Engagement Studies in Adherent Cells.

A prerequisite for successful drugs is effective binding of the desired target protein in the complex environment of a living system. Drug-target engagement has typically been difficult to monitor in physiologically relevant models, and with current methods, especially, while maintaining spatial information. One recent technique for quantifying drug-target engagement is the cellular thermal shift assay (CETSA), in which ligand-induced protein stabilization is measured after a heat challenge. Here, we describe a CETSA protocol in live A431 cells for p38α (MAPK14), where remaining soluble protein is detected in situ, using high-content imaging in 384-well, microtiter plates. We validate this assay concept using a number of known p38α inhibitors and further demonstrate the potential of this technology for chemical probe and drug discovery purposes by performing a small pilot screen for novel p38α binders. Importantly, this protocol creates a workflow that is amenable to adherent cells in their native state and yields spatially resolved target engagement information measurable at the single-cell level.

Inhibitors of the Cysteine Synthase CysM with Antibacterial Potency against Dormant Mycobacterium tuberculosis.

Cysteine is an important amino acid in the redox defense of Mycobacterium tuberculosis, primarily as a building block of mycothiol. Genetic studies have implicated de novo cysteine biosynthesis in pathogen survival in infected macrophages, in particular for persistent M. tuberculosis. Here, we report on the identification and characterization of potent inhibitors of CysM, a critical enzyme in cysteine biosynthesis during dormancy. A screening campaign of 17 312 compounds identified ligands that bind to the active site with micromolar affinity. These were characterized in terms of their inhibitory potencies and structure-activity relationships through hit expansion guided by three-dimensional structures of enzyme-inhibitor complexes. The top compound binds to CysM with 300 nM affinity and displays selectivity over the mycobacterial homologues CysK1 and CysK2. Notably, two inhibitors show significant potency in a nutrient-starvation model of dormancy of Mycobacterium tuberculosis, with little or no cytotoxicity toward mammalian cells.

Mutated variant of Candida antarctica lipase B in (S)-selective dynamic kinetic resolution of secondary alcohols.

An (S)-selective dynamic kinetic resolution of secondary alcohols, employing a mutated variant of Candida antarctica lipase B (CalB) gave products in 84-88% yield and in 90-97% ee.

Synthesis and evaluation of 2-pyridylbenzothiazole, 2-pyridylbenzoxazole and 2-pyridylbenzofuran derivatives as 11C-PET imaging agents for beta-amyloid plaques.

The syntheses and SAR of new series of beta-amyloid binding agents are reported. The effort to optimize signal-to-background ratios for these ligands are described. Compounds 8, 21 and 30 displayed desirable lipophilicity and pharmacokinetic properties. Compounds 8 and 21 were evaluated with in vitro autoradiographic studies and in vivo in APP/PS1 transgenic mice. It is shown that it was possible to increase the signal-to-background ratios compared to PIB 1, as demonstrated by compounds 8 and 21.

Mutant lipase-catalyzed kinetic resolution of bulky phenyl alkyl sec-alcohols: a thermodynamic analysis of enantioselectivity.

The size of the stereoselectivity pocket of Candida antarctica lipase B limits the range of alcohols that can be resolved with this enzyme. These steric constrains have been changed by increasing the size of the pocket by the mutation W104A. The mutated enzyme has good activity and enantioselectivity toward bulky secondary alcohols, such as 1-phenylalkanols, with alkyl chains up to eight carbon atoms. The S enantiomer was preferred in contrast to the wild-type enzyme, which has R selectivity. The magnitude of the enantioselectivity changes in an interesting way with the chain length of the alkyl moiety. It is governed by interplay between entropic and enthalpic contributions and substrates with long alkyl chains are resolved best with E values higher than 100. The enantioselectivity increases with temperature for the small substrates, but decreases for the long ones.