The first structure of polarity suppression protein, Psu from enterobacteria phage P4, reveals a novel fold and a knotted dimer

Banerjee, Ramanuj ; Nath, Seema ; Ranjan, Amitabh ; Khamrui, Susmita ; Pani, Bibhusita ; Sen, Ranjan ; Sen, Udayaditya (2012) The first structure of polarity suppression protein, Psu from enterobacteria phage P4, reveals a novel fold and a knotted dimer Journal of Biological Chemistry, 287 (53). pp. 44667-44675. ISSN 0021-9258

[img]
Preview
PDF - Publisher Version
2MB

Official URL: http://www.jbc.org/content/287/53/44667.short

Related URL: http://dx.doi.org/10.1074/jbc.M112.423202

Abstract

Psu is a capsid decoration protein of bacteriophage P4 and acts as an antiterminator of Rho-dependent transcription termination in bacteria. So far, no structures have been reported for the Psu protein or its homologues. Here, we report the first structure of Psu solved by the Hg2+ single wavelength anomalous dispersion method, which reveals that Psu exists as a knotted homodimer and is first of its kind in nature. Each monomer of Psu attains a novel fold around a tight coiled-coil motif. CD spectroscopy and the structure of an engineered disulfide-bridged Psu derivative reveal that the protein folds reversibly and reassembles by itself into the knotted dimeric conformation without the requirement of any chaperone. This structure would help to explain the functional properties of the protein and can be used as a template to design a minimal peptide fragment that can be used as a drug against Rho-dependent transcription termination in bacteria.

Item Type:Article
Source:Copyright of this article belongs to American Society for Biochemistry and Molecular Biology.
ID Code:114757
Deposited On:04 Jun 2018 05:44
Last Modified:04 Jun 2018 05:44

Repository Staff Only: item control page