Aerolysin and pertussis toxin share a common receptor-binding domain

Rossjohn, Jamie; Buckley, J. Thomas; Hazes, Bart; Read, Randy J.; Parker, Michael W.

doi:10.1093/emboj/16.12.3426

Cited by 55 publications

(55 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1C, 3, and 5). In addition, the region in which sequence similarity is observed is restricted to the pore-forming domain, suggesting that the receptor binding domain is a functionally and structurally autonomic module as suggested previously (48,56). This would explain the similarity in the binding of all Hln isoforms (including the inactive isoform rHln-3) to erythrocyte membranes, as most of the differences between these isoforms are found in the suggested pore-forming region, whereas the rest of the proteins (presumably including the receptor binding domain) are similar.…”

Section: Discussionsupporting

confidence: 57%

Hydralysins, a New Category of β-Pore-forming Toxins in Cnidaria

Sher¹,

Fishman²,

Zhang³

et al. 2005

Journal of Biological Chemistry

View full text Add to dashboard Cite

Cnidaria are venomous animals that produce diverse protein and polypeptide toxins, stored and delivered into the prey through the stinging cells, the nematocytes. These include pore-forming cytolytic toxins such as well studied actinoporins. In this work, we have shown that the non-nematocystic paralytic toxins, hydralysins, from the green hydra Chlorohydra viridissima comprise a highly diverse group of ␤-pore-forming proteins, distinct from other cnidarian toxins but similar in activity and structure to bacterial and fungal toxins. Functional characterization of hydralysins reveals that as soluble monomers they are rich in ␤-structure, as revealed by far UV circular dichroism and computational analysis. Hydralysins bind erythrocyte membranes and form discrete pores with an internal diameter of ϳ1.2 nm. The cytolytic effect of hydralysin is cell type-selective, suggesting a specific receptor that is not a phospholipid or carbohydrate. Multiple sequence alignment reveals that hydralysins share a set of conserved sequence motifs with known pore-forming toxins such as aerolysin, ⑀-toxin, ␣-toxin, and LSL and that these sequence motifs are found in and around the poreforming domains of the toxins. The importance of these sequence motifs is revealed by the cloning, expression, and mutagenesis of three hydralysin isoforms that strongly differ in their hemolytic and paralytic activities. The correlation between the paralytic and cytolytic activities of hydralysin suggests that both are a consequence of receptor-mediated pore formation. Hydralysins and their homologues exemplify the wide distribution of ␤-pore formers in biology and provide a useful model for the study of their molecular mode of action.

show abstract

Section: Discussionsupporting

confidence: 57%

Hydralysins, a New Category of β-Pore-forming Toxins in Cnidaria

Sher¹,

Fishman²,

Zhang³

et al. 2005

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…For one of these domains, the receptor-binding domain, previous work carried out on aerolysin (10,(13)(14)(15) as well as experiments conducted in this study provided evidence to its probable location in D1. Based on this knowledge, scanning was initiated in this region and alanine was chosen for substitution due to its minimal side chain.…”

Section: Mutagenesis Strategysupporting

confidence: 62%

“…Rossjohn et al have shown that D1 of aerolysin contains a motif similar to the carbohydrate-binding domain of pertussis toxin, now named the aerolysin pertussis toxin domain (15). Fusion of this domain to the amino terminus of AT converts it to an aerolysinlike toxin such that it can bind to receptors previously only bound by aerolysin.…”

mentioning

confidence: 99%

Identification of Functional Domains of Clostridium septicum Alpha Toxin

2006

View full text Add to dashboard Cite

Alpha toxin (AT) is the major virulence factor of Clostridium septicum that is a proteolytically activated pore-forming toxin belonging to the aerolysin-like family of toxins. AT is predicted to be a three-domain molecule based on functional and sequence similarity with aerolysin, for which the crystal structure has been solved. In the present study we have substituted the entire primary structure of AT with alanine or cysteine in order to identify those amino acids that comprise functional domains involved in receptor binding, oligomerization and pore formation. These studies revealed that receptor binding is restricted to domain 1 of the AT structure, whereas domains 1 and 3 are involved in oligomerization. These studies also revealed the presence of a putative functional region of AT proximal to the receptor-binding domain, but distal from the pore-forming domain that is proposed to regulate the insertion of the transmembrane β-hairpin of the prepore oligomer.Clostridium septicum is a major cause of non-traumatic gas gangrene in humans, a fulminant form of myonecrosis that can progress to a fatal infection in less than 24 hours with reported mortality rates ranging from 67-100% (1-4). Of its many virulence factors, alpha toxin (AT) is the only lethal factor secreted by this organism (5) and it has recently been shown to be absolutely required for virulence of C. septicum (6). AT is classified as a pore-forming toxin and is a member of the aerolysin-like family of pore-forming toxins. AT and aerolysin share a great deal of structural and sequence similarity (72%) (5), which has allowed for the development of a molecular model of AT using the previously solved crystal structure of aerolysin ( Fig. 1) (7,8). Aerolysin is a two lobed protein in which the small lobe is comprised of domain 1 (D1) and the large lobe is comprised of domains 2-4 (D2-D4, Fig. 1). The primary structure of AT exhibits similarity with the large lobe of aerolysin but it lacks the small lobe structure of about 83 amino acids. Both toxins appear to follow a similar ordered path to form pores in cell membranes (5). Following secretion, they bind to receptors on the cell membrane where they are cleaved into their active form by cell surface proteases, usually furin. Once activated, the toxins oligomerize on the cell surface into a prepore complex followed by insertion of a transmembrane β-barrel into the membrane (8).

show abstract

“…The greater binding could well be due to the higher abundance of N-linked sugars or other oligosaccharides on the apical surface. As recently shown by Hong et al (24), high-affinity binding of aerolysin to its receptor requires not only the glycan core of the GPI-anchored protein but also the interaction of the lectin-like domain 1 of aerolysin (36) with an N-linked sugar on the receptor. Interestingly, it appears that this N-linked sugar must be in close proximity to the GPI anchor, possibly forming a combined binding site, since domain 1 will bind with high affinity only to N-glycans on GPI-anchored proteins.…”

Section: Discussionmentioning

confidence: 90%

Sensitivity of Polarized Epithelial Cells to the Pore-Forming Toxin Aerolysin

et al. 2003

View full text Add to dashboard Cite

Aerolysin is one of the major virulence factors produced by Aeromonas hydrophila, a human pathogen that produces deep wound infection and gastroenteritis. The toxin interacts with target mammalian cells by binding to the glycan core of glycosylphosphatidyl inositol (GPI)-anchored proteins and subsequently forms a pore in the plasma membrane. Since epithelial cells of the intestine are the primary targets of aerolysin, we investigated its effect on three types of polarized epithelial cells: Caco-2 cells, derived from human intestine; MDCK cells, a well-characterized cell line in terms of protein targeting; and FRT cells, an unusual cell line in that it targets its GPI-anchored proteins to the basolateral plasma membrane in contrast to other epithelial cells, which target them almost exclusively to the apical surface. Surprisingly, we found that all three cell types were sensitive to the toxin from both the apical and the basolateral sides. Apical sensitivity was always higher, even for FRT cells. In contrast, FRT cells were more sensitive from the basolateral than from the apical side to the related toxin Clostridium septicum alpha-toxin, which also binds to GPI-anchored proteins but lacks the lectin binding domain found in aerolysin. These observations are consistent with the notion that a shuttling mechanism involving low-affinity interactions with surface sugars allows aerolysin to gradually move toward the membrane surface, where it can finally encounter the glycan cores of GPI-anchored proteins.

show abstract

Aerolysin and pertussis toxin share a common receptor-binding domain

Cited by 55 publications

References 48 publications

Hydralysins, a New Category of β-Pore-forming Toxins in Cnidaria

Hydralysins, a New Category of β-Pore-forming Toxins in Cnidaria

Identification of Functional Domains of Clostridium septicum Alpha Toxin

Sensitivity of Polarized Epithelial Cells to the Pore-Forming Toxin Aerolysin

Contact Info

Product

Resources

About