Review
English
Walid Mottawea, Turki Abujamel, Momen Askoura, and Ibrahim Taher
Department of Biochemistry, Microbiology and Immunology,Faculty of Medicine, University of Ottawa, Canada
Libyan J Infect Dis. 2010;4(1):3-12
Abstract
Listeriosis is a food-borne disease caused by the opportunistic pathogen Listeria monocytogenes. Internalization of Listeria into non phagocytic cells is the crucial step in the pathogenesis of listeriosis. This process is mediated by a group of 25 surface and secretory proteins called internalins. The majority of internalins share an N-terminal superdomain that comprises N-signal peptide, N-cap, leucin rich repeats and inter-repeat region. The attachment of these proteins to the bacterial surface depends on its C-terminal domain. Members containing LPXTG domain can covalently attach to the peptidoglycan moieties, while GW- or WxL containing members, non-covalently, bind lipoteichoic acid fragments. On the other hand, proteins lacking the C-terminal domain are secreted outside the cell. Internalins expression is regulated by the transcriptional activator PrfA and the stress responsive sigma factor σB. Moreover, Quorum sensing peptides might be involved in the regulation of internalins genes expression. Among these 25 proteins, only three members, InlA, InlB, and InlC, have well-characterized roles and host cellular receptors during the pathogenesis of Listeria. Although, other members have unidentified precise role in pathogenesis of L. monocytogenes, their role in virulence has been indicated. The structural and functional diversity among internalins and their roles in the pathogenesis of listeriosis is discussed in this review.
Keywords: Internalins, Listeria monocytogene, Internalin A, Internalin B, Internalin C, Listeriosis
Link/DOI: http://www.nidcc-jid.org.ly/pdf/v4no1/Listeria_monocytogenes_Internalins_A_diverse_protein_family_involved_in_virulence.pdf