BMC Microbiology BioMed Central Review Protein secretion systems in bacterial-host associations, and their description in the Gene Ontology

Virginia Bioinformatics Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
BMC Microbiology (Impact Factor: 2.73). 02/2009; 9 Suppl 1(Suppl 1):S2. DOI: 10.1186/1471-2180-9-S1-S2
Source: PubMed


Protein secretion plays a central role in modulating the interactions of bacteria with their environments. This is particularly the case when symbiotic bacteria (whether pathogenic, commensal or mutualistic) are interacting with larger host organisms. In the case of Gram-negative bacteria, secretion requires translocation across the outer as well as the inner membrane, and a diversity of molecular machines have been elaborated for this purpose. A number of secreted proteins are destined to enter the host cell (effectors and toxins), and thus several secretion systems include apparatus to translocate proteins across the plasma membrane of the host also. The Plant-Associated Microbe Gene Ontology (PAMGO) Consortium has been developing standardized terms for describing biological processes and cellular components that play important roles in the interactions of microbes with plant and animal hosts, including the processes of bacterial secretion. Here we survey bacterial secretion systems known to modulate interactions with host organisms and describe Gene Ontology terms useful for describing the components and functions of these systems, and for capturing the similarities among the diverse systems.

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Available from: Joao Carlos Setubal
    • "Secretion systems pathways (type IV and VI) were discovered in Gram-negative bacteria. They facilitate the transport of DNA, proteins or molecules from the bacterial cytoplasm directly into prokaryote cells (Tseng et al., 2009). The type IV secretion system is the unique type secretion system discovered in Gram-positive bacteria (Melville and Craig, 2013). "
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    • "While growing either in a natural ecosystem or artificial conditions, bacteria secrete intracellular products into their extracellular milieu (Tseng et al. 2009). Secretory products are not only involved in bacterial social behavior , usually referred to as quorum sensing (Molloy 2010) but also in pathogenicity (Lee and Schneewind 2001) and inter-kingdom communication (Hughes and Sperandio 2008; Shen et al. 2012; Furusawa et al. 2013). "
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