title: Analysis of MreB interactors in Chlamydia reveals a RodZ homolog but fails to detect an interaction with MraY.
abstract: Chlamydia is an obligate intracellular bacterial pathogen that has significantly reduced its genome in adapting to the intracellular environment. One class of genes for which the bacterium has few annotated examples is cell division, and Chlamydia lacks FtsZ, a central coordinator of the division apparatus. We have previously implicated MreB as a potential substitute for FtsZ in Chlamydia (Ouellette et al., 2012). Thus, to identify new chlamydial cell division components, we searched for proteins that interacted with MreB. We performed a small-scale screen using a Gateway® compatible version of the Bacterial Adenylate Cyclase Two Hybrid (BACTH) system, BACTHGW, to detect proteins interacting with chlamydial MreB and identified a RodZ (YfgA) homolog. The chlamydial RodZ aligns well with the cytoplasmic domain of E. coli RodZ but lacks the periplasmic domain that is dispensable for rod cell shape maintenance in E. coli. The expression pattern of yfgA/rodZ was similar to that of mreB and ftsI, suggesting that these genes may operate in a common functional pathway. The chlamydial RodZ correctly localized to the membrane of E. coli but was unable to complement an E. coli rodZ mutant strain, likely because of the inability of chlamydial RodZ to interact with the native E. coli MreB. Finally, we also tested whether chlamydial MreB could interact with MraY, as suggested by Gaballah et al. (2011). However, we did not detect an interaction between these proteins even when using an implementation of the BACTH system to allow native orientation of the N- and C-termini of MraY in the periplasm. Thus, further work will be needed to establish this proposed interaction. In sum, we have added to the repertoire of potential cell division proteins of Chlamydia.
authors.affiliation: Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528 Paris, France ; Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota Vermillion, SD, USA.
authors.forename: Scot P
authors.initials: SP
authors.lastname: Ouellette
authors.affiliation: Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota Vermillion, SD, USA.
authors.forename: Kelsey J
authors.initials: KJ
authors.lastname: Rueden
authors.affiliation: Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528 Paris, France ; Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur Paris, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Gauliard
authors.affiliation: Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University Cleveland, OH, USA.
authors.forename: Logan
authors.initials: L
authors.lastname: Persons
authors.affiliation: Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University Cleveland, OH, USA.
authors.forename: Piet A
authors.initials: PA
authors.lastname: de Boer
authors.affiliation: Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528 Paris, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Ladant
keywords: Chlamydia; MreB; RodZ; bacterial two-hybrid system; cell division; protein–protein interactions