The rapid global spread of antibiotic resistance is mediated by conjugative plasmids, yet how these elements establish immediately after entering new bacterial hosts remains poorly understood. Here we...

Atomic resolution in cryo-electron microscopy was first demonstrated six years ago. This was accomplished using 300 kV electron microscopes equipped with new hardware that provided narrower energy spr...

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Natural genetic transformation is a conserved mechanism of bacterial horizontal gene transfer, which is directed entirely by the recipient cell and...

Cryo-EM structure reveals how a ubiquitin-like protein orchestrates assembly of a bacterial weapon system.

Communications Biology - Bacteroidota use the Type IX secretion system to secrete proteins with a conserved C-terminal domain (CTD) secretion signal domain. Type B CTDs require specific shuttle...

Bacterial polymorphic toxins are modular weapons that mediate intermicrobial competition and host interactions by delivering diverse cytotoxic domains through specialized secretion systems. Here, we i...

Marín-Arraiza and colleagues report the cryo-EM structures of an extracellular contractile injection system from Photorhabdus luminescens in extended and contracted states, providing structural insigh...

BindCraft, an open-source, automated pipeline for de novo protein binder design with experimental success rates of 10–100%, leverages AlphaFold2 weights to generate binders with nanomolar affinity without the need for high-throughput screening.

Bacterial polymorphic toxins are modular weapons that mediate inter-microbial competition and host interactions by delivering diverse cytotoxic domains through specialized secretion systems. Here, we ...

We are excited to welcome you in Bordeaux for the 4th edition of the Integrative Structural Biology Meeting (BSI).

Hexameric helicases are nucleotide-driven molecular machines that unwind DNA to initiate replication across all domains of life. Despite decades of intensive study, several critical aspects of their function remain unresolved1: the site and mechanism of DNA strand separation, the mechanics of unwinding propagation, and the dynamic relationship between nucleotide hydrolysis and DNA movement. Here, using cryo-electron microscopy (cryo-EM), we show that the simian virus 40 large tumour antigen (LTag) helicase assembles in the form of head-to-head hexamers at replication origins, melting DNA at two symmetrically positioned sites to establish bidirectional replication forks. Through continuous heterogeneity analysis2, we characterize the conformational landscape of LTag on forked DNA under catalytic conditions, demonstrating coordinated motions that drive DNA translocation and unwinding. We show that the helicase pulls the tracking strand through DNA-binding loops lining the central channel