The innate immunity role of cathepsin-D is linked to Trp-491 and Trp-492 residues of listeriolysin 0
The innate immunity role of cathepsin-D is linked to Trp-491 and Trp-492 residues of listeriolysin 0
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DOI：
10.1111/j.1365-2958.2009.06673.x
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发表时间：
2009-05-01
影响因子：
3.6
通讯作者：
Alvarez-Dominguez, Carmen
中科院分区：
文献类型：
--
作者：
Carrasco-Marin, Eugenio;Madrazo-Toca, Fidel;Alvarez-Dominguez, Carmen
Listeriolysin O (LLO) is a thiol-activated cytolysin secreted by Listeria monocytogenes. LLO and phosphatidylinositol phospholipase C are two essential virulence factors, which this bacterium needs to escape from the phagosomal compartment to the cytoplasm. Cathepsin-D specifically cleaves LLO, between the Trp-491 (tryptophan amino acid in three letter nomenclature) and Trp-492 residues of the conserved undecapeptide sequence, ECTGLAWEWWR, in the domain 4 of LLO (D4). Moreover, these residues also correspond to the phagosomal-binding epitope. Cathepsin-D had no effect on phosphatidylinositol phospholipase C. We have observed that cathepsin-D cleaved the related cholesterol-dependent cytolysin pneumolysin at the same undecapeptide sequence between Trp-435 and Trp-436 residues. These studies also revealed an additional cathepsin-D cleavage site in the pneumolysin D4 domain localized in the 361-GDLLLD-366 sequence. These differences might confer a pathogenic advantage to listeriolysin O, increasing its resistance to phagosomal cathepsin-D action by reducing the number of cleavages sites in the D4 domain. Using Delta LLO/W491A and Delta LLO/W492A bacterial mutants, we reveal that the Trp-491 residue has an important role linked to cathepsin-D in Listeria innate immunity.
