Hungarian Immunology

[Pathogen-associated molecular pattern of bacteria and its recognition by the host]

KOCSIS Béla, EMÕDY Levente

AUGUST 20, 2003

Hungarian Immunology - 2003;2(04)

[Pathogen-associated molecular pattern of bacteria is determined by a molecular complementarity between the host and the microorganism. The process of pathogenesis is initiated through recognition of bacterial components or products by receptor molecules of the host organism. Constant structural components like the lipopolysaccharide in Gramnegative and lipotheichoic acid in Gram-positive bacteria are recognised by receptor molecules present in a wide range of host species, and in this way they elicit interactions and pathologic processes generally present in bacterial infections. At the same time accessorial components (adhesins, capsular material) or extracellular products (exotoxins, enzymes) mediate specific interactions which determine host species or organ specificity according to the molecular structure of the virulence factor and the specific host/organ receptor. The pathogen-associated molecular pattern is subject to changes as genom plasticity in bacteria allows evolution of virulence through recombinations and pathoadaptive mutations. Actual expression of accessorial virulence factors is frequently governed by complicated regulatory mechanisms as an adaptative response to environmental stimuli present in the host.]

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