Defensins identified through molecular de-extinction

Molecular de-extinction is an emerging field that identifies potentially useful molecules throughout evolution. Here, we computationally mine genomes, searching for molecules called defensins, which play a role in host immunity. Our approach leads to the discovery of six undescribed β-defensins, five of which are derived from two different extinct bird species and one from a mammalian species. These organisms included an extinct moa species (Anomalopteryx didiformis) that inhabited New Zealand and the extinct Spix’s macaw (Cyanopsitta spixii), which was endemic to Brazil, as well as the black rhino (Diceros bicornis minor). Evolutionary and structural analyses of the β-defensins are performed to further characterize these molecules. This study identifies molecules from extinct organisms, revealing defensins and opening new avenues for antibiotic discovery.