title: Screening of a Haloferax volcanii Transposon Library Reveals Novel Motility and Adhesion Mutants.
abstract: Archaea, like bacteria, use type IV pili to facilitate surface adhesion. Moreover, archaeal flagella-structures required for motility-share a common ancestry with type IV pili. While the characterization of archaeal homologs of bacterial type IV pilus biosynthesis components has revealed important aspects of flagellum and pilus biosynthesis and the mechanisms regulating motility and adhesion in archaea, many questions remain. Therefore, we screened aHaloferax volcaniitransposon insertion library for motility mutants using motility plates and adhesion mutants, using an adapted air-liquid interface assay. Here, we identify 20 genes, previously unknown to affect motility or adhesion. These genes include potential novel regulatory genes that will help to unravel the mechanisms underpinning these processes. Both screens also identified distinct insertions within the genomic region lying between two chemotaxis genes, suggesting that chemotaxis not only plays a role in archaeal motility, but also in adhesion. Studying these genes, as well as hypothetical geneshvo_2512andhvo_2876-also critical for both motility and adhesion-will likely elucidate how these two systems interact. Furthermore, this study underscores the usefulness of the transposon library to screen other archaeal cellular processes for specific phenotypic defects.
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia 19104, PA, USA. gplegerme@gmail.com.
authors.forename: Georgio
authors.initials: G
authors.lastname: Legerme
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia 19104, PA, USA. evanyang@sas.upenn.edu.
authors.forename: Evan
authors.initials: E
authors.lastname: Yang
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia 19104, PA, USA. rianne.esquivel@gmail.com.
authors.forename: Rianne N
authors.initials: RN
authors.lastname: Esquivel
authors.affiliation: Division of Genetics and Physiology, Department of Biology, University of Turku, Turku 20500, Finland. saija.kiljunen@helsinki.fi.|Immunobiology Program, Research Programs Unit, University of Helsinki, Fi-00014, Helsinki, Finland. saija.kiljunen@helsinki.fi.
authors.forename: Saija
authors.initials: S
authors.lastname: Kiljunen
authors.affiliation: Division of Genetics and Physiology, Department of Biology, University of Turku, Turku 20500, Finland. harri.savilahti@utu.fi.
authors.forename: Harri
authors.initials: H
authors.lastname: Savilahti
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia 19104, PA, USA. pohlschr@sas.upenn.edu.
authors.forename: Mechthild
authors.initials: M
authors.lastname: Pohlschroder
keywords: Haloferax volcanii; adhesion; archaellum; archaeon; biofilm; chemotaxis; flagellum; swimming motility; transposon mutagenesis; type IV pilus