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Some sea slugs sequester chloroplasts from algal food in their intestinal cells and photosynthesize for months. This phenomenon, kleptoplasty, poses a question of how the chloroplast retains its activity without the algal nucleus. There have been debates on the horizontal transfer of algal genes to the animal nucleus. To settle the arguments, this study reported the genome of a kleptoplastic sea slug, Plakobranchus ocellatus, and found no evidence of photosynthetic genes encoded on the nucleus. Nevertheless, it was confirmed that light illumination prolongs the life of mollusk under starvation. These data presented a paradigm that a complex adaptive trait, as typified by photosynthesis, can be transferred between eukaryotic kingdoms by a unique organelle transmission without nuclear gene transfer. Our phylogenomic analysis showed that genes for proteolysis and immunity undergo gene expansion and are up-regulated in chloroplast-enriched tissue, suggesting that these molluskan genes are involved in the phenotype acquisition without horizontal gene transfer.Unlike pharyngeal Neisseria gonorrhoeae, less is known about pharyngeal Chlamydia trachomatis in men who have sex with men (MSM). We reviewed cases of pharyngeal chlamydia in MSM from January to December 2019. The overall prevalence of pharyngeal chlamydia was 75/6613 (1.13%; 95% confidence interval (CI) = 0.9-1.14). The median number of sexual partners was three, four (5%) reported throat symptoms and 20 (26%) were HIV positive. Multi-site and concomitant infection was common rectal chlamydia [39 (52%)], urethral chlamydia [12 (16%)], early syphilis [2 (3%)] and gonorrhoea [14 (19%)]. HIV-positive MSM with pharyngeal chlamydia were older (P = 0.02) and more likely to have had previous syphilis (odds ratio = 4.9; 95% CI = 1.6-14.7; P = 0.005). Further research is needed to explore the characteristics of pharyngeal chlamydia and benefits of increased screening for asymptomatic pharyngeal chlamydia in MSM.What is the strongest Brønsted acid, the strongest base, the strongest oxidizing agent? If not understood in an absolute, once-and-forever sense, the answers to such questions may help at extending and reinforcing the meaning of simple concepts in first-year chemistry courses. Moreover, they serve the purpose of introducing research aspects and linking them to general chemistry.Solid-state NMR spectroscopy is a well-established method to obtain atomic-level information about the structure of inorganic materials, but its use is often limited by low sensitivity. We review how solvent generated dynamic nuclear polarization can be used to increase sensitivity in solid-state NMR of inorganic materials, with emphasis on our recent method for hyperpolarization of proton-free bulk. We use selected examples to show how overall gains in sensitivity can be observed in both the surface and bulk spectra of inorganic compounds such as lithium titanate. The hyperpolarization methods reviewed here can be used to improve NMR sensitivity for a range of inorganic materials.The azido group occupies an important position in modern organic chemistry, broadly used as amine surrogates and as anchors in bioconjugation. Despite their importance, examples of selective direct azidation of inert C(sp³)-H bonds remain limited and often require strong oxidative conditions. Sivelestat Herein, we highlight the use of O-acyl oximes and N-acyloxy imidates as directing groups for the selective iron-catalysed azidation of C(sp³)-H bond with trimethylsilyl azide, giving access to various γ-azido ketones and β-azido alcohols in moderate to excellent yields. The iron catalyst is assumed to play a dual role in these catalytic processes as a reductant to generate the reactive iminyl and imidate radicals, respectively, and as a redox centre to mediate the azido transfer to the translocated carbon radical.Well-defined containers constructed from multiple protein subunits are a unique class of nanomaterial useful in supramolecular chemistry and biology. These protein cages are widespread in nature, where they are responsible for a diversity of important tasks. As such, producing our own designer protein cages, complete with bespoke functionalities, is a promising avenue to new nanodevices, biotechnology and therapies. Herein, we describe how an artificial, computationally designed protein cage can be rationally engineered using supramolecular intuition to produce new functional capsules. Positive supercharging the interior cavity of this porous protein cage enables the efficient encapsulation of oligonucleotides by electrostatically-driven self-assembly. Moreover, the resulting cargo-loaded cages enter mammalian cells and release their cargo, for example siRNA which modulates gene expression. To expand the cargo scope of this proteinaceous container, a higher level of supramolecular complexity can also be introduced. Encapsulation of anionic surfactants affords protein-scaffolded micelles, which are capable of sequestering poorly water-soluble small molecules within their hydrophobic cores. These hybrid particles stably carry bioactive cargo and deliver it intracellularly, thereby increasing potency. Further development of these genetically-encoded materials is ongoing towards specific applications ranging from cell biology to medicine.Cellular homeostasis importantly relies on the correct nucleoplasmic distribution of a large number of RNA molecules and proteins, which are shuttled by specialized transport receptors. The nuclear import receptor importin-5, also called IPO5, RanBP5 or karyopherin β3, mediates the translocation of proteins to the nucleus, and thus regulates critical signaling pathways and cellular functions. The normal function of IPO5 appears to be disrupted in cancer cells due to aberrant overexpression. IPO5 also demonstrated a pivotal role in viral replication. The constant increasing number of publications shows an interest within the scientific community as a therapeutic target due to its pivotal role in protein trafficking.Many chemical concepts can be well defined in the context of quantum chemical theories. Examples are the electronegativity scale of Mulliken and Jaffé and the hard and soft acids and bases concept of Pearson. The sound theoretical basis allows for a systematic definition of such concepts. However, while they are often used to describe and compare chemical processes in terms of reactivity, their predictive power remains unclear. In this work, we elaborate on the predictive potential of chemical reactivity concepts, which can be crucial for autonomous reaction exploration protocols to guide them by first-principles heuristics that exploit these concepts.