title: The Phage-Inducible Chromosomal Islands: A Family of Highly Evolved Molecular Parasites.
abstract: The phage-inducible chromosomal islands (PICIs) are a family of highly mobile genetic elements that contribute substantively to horizontal gene transfer, host adaptation, and virulence. Initially identified in Staphylococcus aureus, these elements are now thought to occur widely in gram-positive bacteria. They are molecular parasites that exploit certain temperate phages as helpers, using a variety of elegant strategies to manipulate the phage life cycle and promote their own spread, both intra- and intergenerically. At the same time, these PICI-encoded mechanisms severely interfere with helper phage reproduction, thereby enhancing survival of the bacterial population. In this review we discuss the genetics and the life cycle of these elements, with special emphasis on how they interact and interfere with the helper phage machinery for their own benefit. We also analyze the role that these elements play in driving bacterial and viral evolution.
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA Glasgow, United Kingdom; email: joser.penades@glasgow.ac.uk.
authors.forename: José R
authors.initials: JR
authors.lastname: Penadés
authors.affiliation: Department of Microbiology and Immunology, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298; email: christie@vcu.edu.
authors.forename: Gail E
authors.initials: GE
authors.lastname: Christie
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000821:virology*; D001435:Bacteriophages / Q000145:classification / Q000235:genetics* / Q000502:physiology; D044404:Genomic Islands; D020071:Interspersed Repetitive Sequences
keywords: bacteriophage; evolution; horizontal gene transfer; molecular piracy; pathogenicity island; virulence