Inflammatory mediator response to Gram-positive and Gram-negative bacteria
in vitro and in middle ear infections
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Inflammatory mediator response to Gram-positive and Gram-negative bacteria in vitro and in middle ear infections
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INTRODUCTION
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The Gram-positive cell wall
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Figure 1: The composition of the Gram-positive and Gram-negative cell wall, respectively, modified from a figure by Agnes Wold. The short peptide chains connecting the Gram-positive peptidoglycan strands usually have L-lysine in the third position, while this residue is occupied by meso-DAP in Gram-negative bacteria.
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Figure 4: Schematic figure of two NOD-like receptors (NLRs), NALP3 and NOD1.
Upon activation of NOD1 or NOD2, a conformation change occurs, which enables the protein to oligomerize. Recruitment of RIP2 results in activation of NF-κB and MAPKs and subsequent transcription of genes encoding inflammatory molecules including cytokines.
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