Pseudomonas aeruginosa colonies develop spatial patterns through cooperative swarming. During experimental evolution experiments, cheaters emerged, leading to the disruption of the spatial patterns and a decline in population fitness. The authors found that populations were more vulnerable to invading cheaters in a spatially extended system due to a higher level of cooperation. This collapse of cooperation during microbial range expansion is shown to be tied to its spatial dynamics: spatial structure promoted the invasion of cheaters, while in well-mixed cultures cheaters remained at low frequencies.

See Luo et al.

This image shows fluorescently labelled extracellular vesicles from semen (red) binding to Axl (green), a broadly expressed phosphatidylserine-binding receptor. This interaction interferes with infection by viruses exposing phosphatidylserine to exploit the immunosuppressive uptake mechanism of apoptotic membranes. Given their abundance in semen and saliva, extracellular vesicles may serve as an innate defence against sexual or oral transmission of viruses applying apoptotic mimicry such as Zika, Chikungunya or Ebola.

See Groß et al.

Decomposing remains, whether human or other animal, are attractive to organisms across the tree of life because they are concentrated sources of nutrients and moisture. Blow flies (likely to be Chrysomya rufifacies in this photo), for which larval stages are obligate flesh feeders, are key vectors of a specialist carrion decomposer microbial network that appears universal across terrestrial environments.

See Burcham et al.

This image shows type 10 secretion system (T10SS)-mediated Tc toxin release by Yersinia entomophaga, as captured by cryo-electron tomography. Spanin-mediated membrane fusion triggers bacterial lysis and the explosive discharge of pre-assembled toxins by a subset of the bacterial population.

See Sitsel et al.

This image shows confocal microscopy of macrophages with the DNA-sensing enzyme cGAS (GFP) translocating from the nucleus to the cytosol in response to the phagocytosis of extracellular vesicles isolated from the fungal pathogen Candida albicans.

See Harding et al.