Abstract
We report on specific magneto-capturing followed by Multidimensional Protein Identification Technology (MudPIT) for the analysis of surface-exposed proteins of intact cells of the bacterial opportunistic pathogen Pseudomonas aeruginosa. The magneto-separation of cell envelope fragments from the soluble cytoplasmic fraction allowed the MudPIT identification of the captured and neighboring proteins. Remarkably, we identified 63 proteins captured directly by nanoparticles and 67 proteins embedded in the cell envelope fragments. For a high number of proteins, our analysis strongly indicates either surface exposure or localization in an envelope district. The localization of most identified proteins was only predicted or totally unknown. This novel approach greatly improves the sensitivity and specificity of the previous methods, such as surface shaving with proteases that was also tested on P. aeruginosa. The magneto-capture procedure is simple, safe, and rapid, and appears to be well-suited for envelope studies in highly pathogenic bacteria.
Highlights
The bacterial cell envelope is a highly-structured multi-layer that guarantees cell integrity and protection from environmental adversities while supporting in-out passage of nutrients and wastes [1]
In Gram-negative bacteria, the surface layer consists of an outer membrane (OM) of phospholipids and lipopolysaccharides
In this work we aimed to develop alternative tools for the proteomic analysis of the bacterial cell envelope
Summary
The bacterial cell envelope is a highly-structured multi-layer that guarantees cell integrity and protection from environmental adversities while supporting in-out passage of nutrients and wastes [1]. Surface proteins localize in OM and participate in interactions with the environment, sensing the chemical and physical conditions of the surroundings and transmitting appropriate signals to the cytoplasm [2]. These functions include adhesion to and, when possible, invasion of physical and biological supports (e.g. host cells for pathogens), as well as the transport of nutrient molecules. Given these essential roles in bacterial life and pathogenicity, identification and characterization of envelope proteins may lead to novel antibacterial targets. Since surface proteins face the host immune system, they could be the basic elements of effective vaccines [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
