Geospatial modelling shows an overall decline in morbidity and mortality due to lower respiratory infections in Africa from 2000 to 2017, but also identifies subnational areas with residual high risk.

See Reiner, R. C. et al.

Magnetotactic bacteria must assemble magnetosomes into a linear chain that orients the cell along magnetic fields, yet how spiral bacteria with highly curved surfaces accomplish this is unclear. Here, MamY is shown to assemble into linear structures that serve as a scaffold for magnetosomes in magnetotactic spirilla.

See Toro-Nahuelpan, M. et al.

The crystal structure of a complex between the tail fibre and tail fibre assembly (Tfa) protein of Escherichia coli phage Mu reveals the mechanisms by which Tfa regulates fibre assembly and multimerization.

See North, O. I. et al.

Tigecycline and the newly FDA-approved eravacycline and omadacyclin are last-line antibiotics used to treat multi-drug-resistant bacterial infections. In this issue, Wang and colleagues as well as Liu and colleagues report the discovery of the mobile genes tet(X3) and tet(X4) on conjugative plasmids in Enterobacteriaceae and Acinetobacter isolated from humans, meat for consumption and animals. These genes confer resistance to tetracyclines, including tigecycline, eravacycline and omadacycline. The cover depicts an artistic representation of different bacterial species breaking through last-line antibiotics.

See Wang et al. and Liu et al..

Direct interaction of influenza virus with Gram-positive and Gram-negative bacterial pathogens of the respiratory tract results in increased bacterial adherence to respiratory epithelial cells in culture and in higher bacterial burdens in vivo.

See Rowe, H. M. et al.

A genome-wide CRISPR interference screen of the fast-growing Vibrio natriegens bacterium elucidates the make-up of minimal genomes and the metabolic pathways enabling rapid bacterial replication.

See Lee, H. H. et al.

Cryo-electron tomography was used to study the initial steps of phage P22 infection of Salmonella enterica sv. Typhimurium, revealing how the phage forms a channel through the host outer and inner membranes to translocate its genome into the bacterial cytoplasm.

See Wang et al.

By combining a deep mutational scanning strategy with molecular modelling, electron microscopy as well as cellular and biochemical approaches, the authors identify key amino acids in the C-terminal domain of the Zika virus envelope protein that regulates viral replication in mosquito and human cells.

See Setoh et al.

By combining a yeast single-cell RNA-seq method that counts transcript start sites in a strand- and isoform-specific manner with index sorting, the authors uncover a linear relationship between cell size and RNA content and extreme cell heterogeneity in the expression of metabolic genes.

See Nadal-Ribelles et al.

Combining the plaque assay with mass spectrometry imaging allowed metabolites produced during viral infection of the alga Emiliania huxleyi to be mapped at high spatiotemporal resolution, and identified a shift in lipid metabolism.

See Schleyer et al.

The discovery of an alternative squalene epoxidase (AltSQE), belonging to the fatty acid hydroxylase superfamily in the diatom Phaeodactylum tricornutum and other eukaryotic lineages, solves the mystery of the existence of a steroid biosynthesis pathway in eukaryotes that lack the canonical flavoprotein SQE.

See Pollier et al.

Infectious diseases remain a major cause of morbidity and mortality globally. This month’s issue includes a special Focus on Infectious Disease that highlights new approaches to better prevent, detect and treat infections.

See Focus