%0 Journal Article %T Burkholderia cepacia Complex: Emerging Multihost Pathogens Equipped with a Wide Range of Virulence Factors and Determinants %A S¨ªlvia A. Sousa %A Christian G. Ramos %A Jorge H. Leit£¿o %J International Journal of Microbiology %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/607575 %X The Burkholderia cepacia complex (Bcc) comprises at least 17 closely-related species of the -proteobacteria subdivision, widely distributed in natural and man-made inhabitats. Bcc bacteria are endowed with an extraordinary metabolic diversity and emerged in the 1980s as life-threatening and difficult-to-treat pathogens among patients suffering from cystic fibrosis. More recently, these bacteria became recognized as a threat to hospitalized patients suffering from other diseases, in particular oncological patients. In the present paper, we review these and other traits of Bcc bacteria, as well as some of the strategies used to identify and validate the virulence factors and determinants used by these bacteria. The identification and characterization of these virulence factors is expected to lead to the design of novel therapeutic strategies to fight the infections caused by these emergent multidrug resistant human pathogens. 1. The Burkholderia cepacia Complex¡ªAn Overview Members of the Burkholderia cepacia complex (Bcc) are gram-negative bacteria of the -proteobacteria subdivision and include plant, animal, and human pathogens, with a widespread distribution in natural and man-made inhabitats [1]. These bacteria exhibit an extraordinary metabolic versatility, allowing their adaptation to a wide range of environments. Among the Bcc bacteria, several strains of potential environmental application have been identified due to their ability to degrade pollutants in water and soils (e.g., crude oils, herbicides, recalcitrant aromatic compounds, and xenobiotics). A summary of Burkholderia strains capable of degrading recalcitrant xenobiotics is available at the Biodegradative Strain Database (http://bsd.cme.msu.edu/). Several Bcc strains are also able to produce antifungal compounds and to fix atmospheric nitrogen [2]. Recent evidence suggests that members of the Burkholderia genus are ancient nitrogen-fixing symbionts of Mimosa legumes particularly adapted to acidic infertile soils [3]. Due to the ability of some strains to promote plant growth, bacteria of the Bcc have attracted significant commercial interest as biocontrol, bioremediation, and plant-growth promoting agents, mainly due to their ability to colonize the rhizosphere of several crops of economical interest, like corn, maize, rice, pea, and sunflower [2]. However, these bacteria have also emerged as important human pathogens and the risks associated with the agricultural uses of Bcc strains remain unclear. There is a general consensus that the large-scale use of organisms of the Burkholderia %U http://www.hindawi.com/journals/ijmicro/2011/607575/