Bacillus thuringiensis (Bt) bacteria produce insecticidal Cry and Cyt proteins used in the biological control of different insect pests. In this review, we will focus on the 3d‑Cry toxins that represent the biggest group of Cry proteins and also on Cyt toxins. The 3d‑Cry toxins are...

Membrane‑active peptides exhibit antimicrobial, channel‑forming and transport activities and have therefore early on been interesting targets for biophysical investigations. When the peptide‑lipid interactions are studied a dynamic view emerges in which the peptides change conformation upon...

The parasitic mushroom Laetiporus sulphureus produces a family of lectins (LSL´s) sharing 80‑90% sequence identity that possesses a low but significant sequence similarity to the bacterial pore‑forming toxins mosquitocidal toxin Mtx‑2 from Bacillus sphaericus and α toxin from Clostridium...

Cobra venom contains cardiotoxins (CTXs) that induce tissue necrosis and systolic heart arrest in bitten victims. CTX‑induced membrane pore formation is one of the major mechanisms responsible for the venom’s designated cytotoxicity. This chapter examines how glycoconjugates such as heparan...

Pore‑forming proteins (PFPs) possess the intriguing property that they can exist either in a stable water‑soluble state or as an integral membrane pore. These molecules can undergo large conformational changes in converting between these two states. Much of what we know about how these...

Actinoporins are potent pore‑forming toxins produced by sea anemones. They readily form pores in membranes that contain sphingomyelin. Molecular mechanism of pore formation involves recognition of membrane sphingomyelin, firm binding to the membrane accompanied by the transfer of the...

The proteins of the Bcl‑2 family regulate the release of the apoptotic factors from mitochondria during apoptosis, a key event in physiological cell death. Although their molecular mechanisms remain unclear, the Bcl‑2 proteins have been proposed to directly control the permeability of the...

Certain strains of Escherichia coli, Salmonella enterica and Shigella flexneri produce a pore‑forming toxin hemolysin E (HlyE), also known as cytolysin A (ClyA) and silent hemolysin, locus A (SheA). HlyE lyses erythrocytes and mammalian cells, forming transmembrane pores with a minimum internal...

The cholesterol‑dependent cytolysins (CDCs) are part of a large family of pore‑forming proteins that include the human proteins perforin and the complement membrane attack complex. The activity of all family members is focused on membranes, but the proteins are themselves involved in a...

Bilayer lipids, far from being passive elements, have multiple roles in polypeptide‑dependent pore formation. Lipids participate at all stages of the formation of pores by providing the binding site for proteins and peptides, conditioning their active structure and modulating the molecular...

Over 20 clinical syndromes have been described as amyloid diseases. Pathologically, these illnesses are characterized by the deposition in various tissues of amorphous, Congo red staining deposits, referred to as amyloid. Under polarizing light microscopy, these deposits exhibit characteristic...

Colicins are water soluble toxins secreted by E. coli cells to kill other E. coli and related species. To do this they need to cross the outer membrane, periplasm and inner membrane. Pore forming colicins, as their name suggests form a voltage dependent pore in the inner membrane. This chapter...

In every living cell, the lipid bilayer membrane is the ultimate boundary between the contents of the cell and the rest of universe. A single breach in this critical barrier is lethal. For this reason, the bilayer’s permeability barrier is the point of attack of many offensive and defensive...