6tup

Cryo-EM structure of Pf4 bacteriophage coat protein with single-stranded DNACryo-EM structure of Pf4 bacteriophage coat protein with single-stranded DNA

6tup, resolution 3.20Å Show:Asymmetric Unit Biological Assembly Structural highlights 6tup is a 2 chain structure with sequence from Pseudomonas aeruginosa pao1 and Pseudomonas virus pf1. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed The opportunistic pathogen Pseudomonas aeruginosa is a major cause of antibiotic-tolerant infections in humans. P. aeruginosa evades antibiotics in bacterial biofilms by up-regulating expression of a symbiotic filamentous inoviral prophage, Pf4. We investigated the mechanism of phage-mediated antibiotic tolerance using biochemical reconstitution combined with structural biology and high-resolution cellular imaging. We resolved electron cryomicroscopy atomic structures of Pf4 with and without its linear single-stranded DNA genome, and studied Pf4 assembly into liquid crystalline droplets using optical microscopy and electron cryotomography. By biochemically replicating conditions necessary for antibiotic protection, we found that phage liquid crystalline droplets form phase-separated occlusive compartments around rod-shaped bacteria leading to increased bacterial survival. Encapsulation by these compartments was observed even when inanimate colloidal rods were used to mimic rod-shaped bacteria, suggesting that shape and size complementarity profoundly influences the process. Filamentous inoviruses are pervasive across prokaryotes, and in particular, several Gram-negative bacterial pathogens including Neisseria meningitidis, Vibrio cholerae, and Salmonella enterica harbor these prophages. We propose that biophysical occlusion mediated by secreted filamentous molecules such as Pf4 may be a general strategy of bacterial survival in harsh environments. Phage liquid crystalline droplets form occlusive sheaths that encapsulate and protect infectious rod-shaped bacteria.,Tarafder AK, von Kugelgen A, Mellul AJ, Schulze U, Aarts DGAL, Bharat TAM Proc Natl Acad Sci U S A. 2020 Feb 18. pii: 1917726117. doi:, 10.1073/pnas.1917726117. PMID:32071243 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.