Phage detection by a bacterial NLR-related protein is mediated by DnaJ.

Bacteria encode a wide range of antiphage systems and a subset of these proteins are homologous to components of the human innate immune system. Mammalian nucleotide-binding and leucine-rich repeat containing proteins (NLRs) and bacterial NLR-related proteins use a central NACHT domain to link infection detection with initiation of an antimicrobial response. Bacterial NACHT proteins provide defense against both DNA and RNA phages.

Bacterial NLR-related proteins protect against phage.

Bacteria use a wide range of immune pathways to counter phage infection. A subset of these genes shares homology with components of eukaryotic immune systems, suggesting that eukaryotes horizontally acquired certain innate immune genes from bacteria. Here, we show that proteins containing a NACHT module, the central feature of the animal nucleotide-binding domain and leucine-rich repeat containing gene family (NLRs), are found in bacteria and defend against phages.

A Metagenomic Investigation of Spatial and Temporal Changes in Sewage Microbiomes across a University Campus.

Wastewater microbial communities are not static and can vary significantly across time and space, but this variation and the factors driving the observed spatiotemporal variation often remain undetermined. We used a shotgun metagenomic approach to investigate changes in wastewater microbial communities across 17 locations in a sewer network, with samples collected from each location over a 3-week period. Fecal material-derived bacteria constituted a relatively small fraction of the taxa found in the collected samples, highlighting the importance of environmental sources to the sewage microbiome.

The Linguistics of Bacterial Conflict Systems Reveal Ancient Origins of Eukaryotic Innate Immunity.

The arms race between bacteria and their competitors has produced an astounding variety of conflict systems that are shared via horizontal gene transfer across bacterial populations. In this issue of the , Burroughs and Aravind investigate how these biological conflict systems have been mixed and matched into new configurations, often with novel protein domains (A. M.