Structural Basis and Functional Implications of the Membrane Pore-Formation Mechanisms of Bacterial Pore-Forming Toxins
Pore-forming toxins (PFTs) are a distinct class of membrane-damaging protein toxins documented in a wide array of life forms ranging from bacteria to humans. PFTs are known to act as potent virulence factors of the bacterial pathogens. Bacterial PFTs are, in general, secreted as water-soluble molecules, which upon encountering target host cells assemble into transmembrane oligomeric pores, thus leading to membrane permeabilization and cell death. Interaction of the PFTs with the target host cells can also lead to plethora of cellular responses having critical implications for the bacterial pathogenesis processes, host-pathogen interactions, and host immunity. In this review, we present an overview of our current understanding of the structural aspects of the membrane pore-formation processes employed by the bacterial PFTs. We also discuss the functional implications of the PFT mode of actions, in terms of eliciting diverse cellular responses.
KeywordsPore-forming toxin Cholesterol-dependent cytolysin Membrane Oligomerization
We acknowledge the support through funding from the Department of Biotechnology (DBT), India [DBT Grant No. BT/PR12141/BRB/10/1343/2014; DBT Grant No. BT/HRD/NBA/37/01/2014 (x)], and also through funding under the Centre of Excellence (COE) in Frontier Areas of Science and Technology (FAST) programme of the Ministry of Human Resource Development, Government of India, in the area of protein science, design, and engineering. We also thank the Indian Institute of Science Education and Research (IISER), Mohali, for the support.
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