title: Computational and experimental analysis of the secretome of Methylococcus capsulatus (Bath).
abstract: The Gram-negative methanotroph Methylococcus capsulatus (Bath) was recently demonstrated to abrogate inflammation in a murine model of inflammatory bowel disease, suggesting interactions with cells involved in maintaining mucosal homeostasis and emphasizing the importance of understanding the many properties of M. capsulatus. Secreted proteins determine how bacteria may interact with their environment, and a comprehensive knowledge of such proteins is therefore vital to understand bacterial physiology and behavior. The aim of this study was to systematically analyze protein secretion in M. capsulatus (Bath) by identifying the secretion systems present and the respective secreted substrates. Computational analysis revealed that in addition to previously recognized type II secretion systems and a type VII secretion system, a type Vb (two-partner) secretion system and putative type I secretion systems are present in M. capsulatus (Bath). In silico analysis suggests that the diverse secretion systems in M.capsulatus transport proteins likely to be involved in adhesion, colonization, nutrient acquisition and homeostasis maintenance. Results of the computational analysis was verified and extended by an experimental approach showing that in addition an uncharacterized protein and putative moonlighting proteins are released to the medium during exponential growth of M. capsulatus (Bath).
authors.affiliation: Østfold Hospital Trust, Fredrikstad, Norway; Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway.
authors.forename: Stine
authors.initials: S
authors.lastname: Indrelid
authors.affiliation: Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway.
authors.forename: Geir
authors.initials: G
authors.lastname: Mathiesen
authors.affiliation: Østfold Hospital Trust, Fredrikstad, Norway; Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway; Department of Gastrointestinal and Children Surgery, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Morten
authors.initials: M
authors.lastname: Jacobsen
authors.affiliation: Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway.
authors.forename: Tor
authors.initials: T
authors.lastname: Lea
authors.affiliation: Østfold Hospital Trust, Fredrikstad, Norway; Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway.
authors.forename: Charlotte R
authors.initials: CR
authors.lastname: Kleiveland
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D058947:Bacterial Secretion Systems / Q000378:metabolism*; D003198:Computer Simulation; D020619:Methylococcus capsulatus / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems