Cover image

Cover In this issue, the isolation of individual segmented filamentous bacteria (SFB) from the gut of a monocolonized mouse using a microfluidic device, and the sequencing of their genomes, is described. The colored bases in the DNA sequences represent sequence polymorphisms among individual SFB filaments. The filaments represent life cycle stages driven by cell differentiation and include multicellular filaments, holdfasts, and spores. The SFB genomes encode various proteins that facilitate survival in the intestine and interaction with the host; among these is a novel family of ADP-ribosyl transferases, illustrated as hexagons with arrows. (Cover illustration by Sünje J. Pamp. [For details, see Pamp et al., pp. 1107–1119.])