Abstract Cag type IV secretion system (CagT4SS) mediates the translocation of diverse substrates and is critical for the Helicobacter pylori pathogenesis. Its assembly is initiated by the central cylinder comprising CagX, CagY and CagM, however, the order and detailed mechanism remain unclear. Here, we characterize their respective self-oligomerizing properties and in vitro reconstitute subcomplexes that recapitulate features of the native nanomachine. By integrating multiple biophysical analyses, the structures, binding kinetics and conformational dynamics of assembly intermediates are shown. The assembly begins with self-oligomerization of CagX, followed by CagY association to form a stable periplasmic ring complex (PRC). CagM is subsequently coupled with CagX through multimerization of dimers, with CagY enhancing both the stability and cooperativity of its association. Our findings show the spatial and temporal nature of the assembly process, in particular the significance of PRC substructure, providing mechanistic insights into the biogenesis of bacterial T4SSs beyond static models.
A major puzzle in high-Tc superconductivity is the origin of the “Planckian” relaxation rate 1/τ underlying the linear-in-temperature resistivity in the strange-metal state, which persists up to very high temperatures. Implicit in theoretical discussions is the assumption that 1/…
Abstract We demonstrate that standard wafer fabrication can produce free-standing, mechanically stable, doubly-curved 3D structures with prescribed Gaussian curvature — a capability not previously achieved through semiconductor manufacturing. The stability of the deployed structu…
Recent work suggests that soil-borne viruses play an important role in controlling carbon (C) cycling and stocks. However, the contribution of individual prophage (i.e., temperate phages residing within bacterial hosts during lysogenic cycle) to C degradation remains largely undo…
Flexible impact-resistant materials are essential for defense, transportation, and biomedical engineering due to their ability to combine strength, energy dissipation, and compliance. While nature offers robust solutions like beetle elytra or mantis shrimp hammers, designing mate…
Abstract Hereditary transthyretin amyloidosis (ATTRv) is a fatal autosomal dominant disease characterized by systemic deposition of transthyretin (TTR) amyloid fibrils, leading to progressive neuropathy and cardiomyopathy. More than 130 pathogenic mutations in the TTR gene have b…
Abstract Soil moisture across South America exhibits coherent spatial patterns shaped by upwind terrestrial conditions, yet their downwind propagation remains poorly quantified. We develop an observation-driven framework integrating atmospheric transport trajectories with deep le…