Volume 15 Issue 3, March 2019

Cell envelope assembly during V snapping, an unusual method of cell division in Actinobacteria, is mechanistically different than that seen during cell division of many other bacteria.

Holliday junction resolvases lock dynamic DNA four-way junctions into specific structural conformations for symmetric DNA cleavage. Single-molecule studies now reveal that resolvases can relax their grip, enabling Holliday junction conformer transitions and branch migration in the enzyme-bound form.

A new method introduces ubiquitin or ubiquitin-like proteins at specific sites in any protein without the requirement of the cellular ubiquitylation machinery. This will help decipher the code by which these modifications control cellular processes.

A chemoenzymatic tagging approach was developed and identified eukaryotic host proteins that are O-glycosylated by SetA from Legionella. The SetA-consensus motif was applied to recombinant proteins yielding a site-specific O-glucosylation method.

Engineering of toehold-gated guide RNA (thgRNA) by tethering toehold riboswitches to sgRNAs enables the activation of CRISPR–Cas9 genome editing or transcriptional regulation in response to complementary synthetic or endogenous cellular RNAs.

Assembly of the mycobacterial cell envelope layers, including peptidoglycan (PG) and the mycomembrane (MM), is synchronous during elongation, when a mobile fraction of the MM diffuses into the septum after thinning of the diffusion barrier formed by PG.

Epigenome profiling in combination with imaging-based chemosensitivity and integrative bioinformatic analysis establishes a method for detecting therapy-induced vulnerabilities, as shown here for ibrutinib-treated chronic lymphocytic leukemia.

The sensitivities of a set of bacterial metal-sensing transcriptional regulators explain how a protein, such as the cobalt chelatase CbiK, is metalated with its cognate metal in cells rather than mis-metalated with more tightly binding metals.

Discovery and exploitation of inherent reaction features of chlorofluoroacetamide (CFA) as a warhead such as low off-target activity and reversible reactivity with cysteine enable specific covalent inhibition of targeted kinases.

Live-cell imaging and virus trafficking studies show that the host innate immune receptor IFITM3 localizes with endocytic vesicles that fuse with incoming viruses to ultimately enhance their traffic to lysosomes.

Single-molecule analysis reveals a novel binding state of Holliday junction (HJ) resolving enzymes where the enzymes partially dissociate from the HJ and allowing nearly unencumbered HJ dynamics, suggesting coupled branch migration and HJ resolution.

A method combining genetic-code expansion, bioorthogonal Staudinger reduction and sortase-mediated transpeptidation enables site-specific and orthogonal modification of proteins with ubiquitin and SUMO in vitro and in living cells.

Structural and biochemical analysis of the AtaR–AtaT toxin–antioxin system reveals that AtaR traps AtaT in a precatalytic monomeric state and forms a heterohexameric complex to neutralize AtaT and repress transcription of the operon.

The reconstitution of gentamicin B biosynthesis reveals the existence of multiple new intermediates and branching pathways and enables the identification of factors that contribute to the low levels of the natural product in the native producer.

An allosteric inhibitor of the proteolytic activity of the CBM signalosome complex scaffolding protein MALT1 acts as a pharmacological chaperone to stabilize a mutant MALT1 carried by an immunodeficient patient.