REVISIÓN Completely sequenced genomes of pathogenic bacteria: A review Eduard Guzmán a,b , Antoni Romeu b and Santiago Garcia-Vallve b a Institut Català de la Salut. Àrea Bàsica de Salut. Tarragona. b Evolutionary Genomics Group. Biochemistry and Biotechnology Department. Rovira i Virgili University (URV). Campus Sescelades. Tarragona. Spain. posibilitar la identificación de las claves genéticas responsables de la diferente condcta de aquellos microorganismos patógenos bacterianos relacionados entre sí. Este artículo revisa cuáles son los genomas bacterianos que han sido ya secuenciados o lo están siendo en el momento actual. El artículo también describe qué tareas han de llevarse a cabo cuando se ha obtenido la secuencia completa de un genoma y analiza los beneficios de disponer de la secuencia genómica de bacterias patógenas. Key words: Genómica. Genoma bacteriano completamente secuenciado. Bacteria patógena. Introduction Most of our knowledge on the organization and dynam- ics of bacterial genomes has been obtained after years of sequencing individual genes or genome fragments. We have now entered the “genomic era” 1 , in which the task of sequencing a complete bacterial genome is becoming easi- er. A useful image to illustrate the impact of genomic re- search is to imagine a building firmly resting on Genome Projects, with three floors that represent the impact of genomics on biology, health, and society, respectively 2 . Seen in this way, genomics is a central discipline of bio- medical research. The information extracted from genome projects will enable us to convert genome-based knowl- edge into health benefits and help to develop powerful new therapeutic and preventive approaches to infectious dis- eases 2 . This article reviews the genomes from pathogenic bacteria that have been or are currently being sequenced, briefly explains what “sequencing a genome” means, de- scribes the main tasks to be accomplished after the genome sequence is obtained, and discusses the benefits of obtaining the complete sequence of bacterial pathogens. Organization and dynamics of bacterial genomes Bacterial genomes usually consist of a single circular chromosome between 0.5 and 10 megabases (Mb) in size that contains a unique origin and terminus of replication 3 . There are exceptions, however, such as linear chromo- somes and bacteria that posses two or more chromosomes. Among pathogenic bacteria, Vibrio, Burkholderia, Lepto- spira and Brucella species are those with two or more chromosomes. Certain bacteria can also present one or Six out of ten completely sequenced bacterial genomes are pathogenic or opportunistic bacteria. The genome sequence of at least one strain of all the principal pathogenic bacteria will soon be available. This information should enable us to identify genes that encode virulence factors. As these genes are potential targets for drugs and vaccines, their identification should have considerable repercussions on prevention, diagnosis, and treatment of the main bacterial infectious diseases. Comparison of genome sequences of several strains of the same species should allow identification of the genetic clues responsible for the differing behavior of related bacterial pathogens. This article reviews the genomes from pathogenic bacteria that have been or are currently being sequenced, describes the main tasks to be accomplished after a genome sequence becomes available, and discusses the benefits of having the genome sequence of bacterial pathogens. Key words: Genomics. Complete bacterial genomes. Pathogenic bacteria. Genomas completamente secuenciados de bacterias patógenas: una revisión Seis de cada 10 genomas bacterianos cuya secuenciación se ha completado son de bacterias patógenas o que causan infecciones oportunistas. Muy pronto estarán disponibles las secuencias de los genomas de al menos una cepa de cada una de las principales bacterias patógenas. Esta información tendría que permitirnos identificar los genes que codifican factores de virulencia. Al ser dichos genes dianas potenciales para desarrollar fármacos y vacunas, su identificación debería tener considerables repercusiones en el diagnóstico, prevención y tratamiento de las principales infecciones bacterianas conocidas. La comparación de secuencias genómicas de las diversas cepas de una misma especie, tendría que Correspondence: E. Guzmán. Evolutionary Genomics Group. Biochemistry and Biotechnology Department. Rovira i Virgili University (URV). Campus Sescelades. Marcel.li Domingo, s/n. 43007 Tarragona. Spain. E-mail: eduardo.guzman@urv.net Manuscript received on June 28, 2006; accepted on September 7, 2006. 88 Enferm Infecc Microbiol Clin 2008;26(2):88-98 Document downloaded from http://www.elsevier.es, day 20/06/2017. This copy is for personal use. Any transmission of this document by any media or format is strictly prohibited.