Turtle beta-defensin 1 (TBD-1)

Turtle beta-defensin 1 (TBD-1) is a 40-residue antimicrobial peptide (AMP) originally isolated from the leukocytes of the European pond turtle (Emys orbicularis). It represents the first defensin identified in reptilian leukocytes and shares high structural homology with avian and mammalian beta-defensins, characterized by three conserved disulfide bonds. TBD-1 exhibits potent, broad-spectrum activity against Gram-positive and Gram-negative bacteria, including Escherichia coli and Listeria monocytogenes, as well as antifungal activity against Candida albicans. Beyond its direct microbicidal effects, which typically involve the disruption of microbial lipid bilayers, TBD-1 is thought to play a role in modulating the innate immune response through chemotactic signaling. In the context of drug development, TBD-1 and its analogs are being explored as potential templates for novel anti-infective agents and as candidates for anticancer therapy due to their ability to selectively target and lyse malignant cell membranes.

Other names

Turtle beta-defensin-1TBD1