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Title: Structural mechanisms of Tad pilus assembly and its interaction with an RNA virus
Caulobacter crescentusTad (tight adherence) pili, part of the type IV pili family, are crucial for mechanosensing, surface adherence, bacteriophage (phage) adsorption, and cell-cycle regulation. Unlike other type IV pilins, Tad pilins lack the typical globular β sheet domain responsible for pilus assembly and phage binding. The mechanisms of Tad pilus assembly and its interaction with phage ΦCb5 have been elusive. Using cryo–electron microscopy, we unveiled the Tad pilus assembly mechanism, featuring a unique network of hydrogen bonds at its core. We then identified the Tad pilus binding to the ΦCb5 maturation protein (Mat) through its β region. Notably, the amino terminus of ΦCb5 Mat is exposed outside the capsid and phage/pilus interface, enabling the attachment of fluorescent and affinity tags. These engineered ΦCb5 virions can be efficiently assembled and purified inEscherichia coli, maintaining infectivity againstC. crescentus, which presents promising applications, including RNA delivery and phage display.  more » « less
Award ID(s):
1902392
PAR ID:
10556604
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
18
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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