S7-8 Wed Jan 6 16:00 – 16:30 Parallels of melanization in Cryptococcus neoformans and Anopheles gambiae Camacho, E*; Anglero-Rodriguez, Y; Smith, DFQ; Jacobs, E; Dong, Y; Cordero, RJB; Dimopoulos, G; Casadevall, A; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD ; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD ecamach2@jhu.edu https://www.jhsph.edu/faculty/directory/profile/4003/emma-camacho
Melanins are natural pigments synthesized by organisms in all biological kingdoms. In fungi, melanins are components of the cell wall that provide protection against biotic and abiotic elements. In insects, these biopolymers are essential on wound healing and innate immunity. Melanin biosynthesis in both fungi and insects is mediated by a phenoloxidase that catalyzes the oxidation of phenolic substrates. A better understanding of the chemical nature of melanin and its role in critical physiological processes of malaria-transmitting mosquitoes is highly valuable to the development of novel biocontrol strategies. In this study, we used spectroscopy, high-resolution microscopy, proteomics, and biochemical methodologies to analyze mosquito melanin involved in immune defense (melanotic capsules) and structural barriers (cuticle). Our data showed that A. gambiae melanotic capsules are characterized by signature properties of eumelanins closely associated with proteins. Furthermore, we observed that a polyphenol diet reduces susceptibility to the human malaria parasite and enhances cuticular pigmentation and heat absorption. These features are remarkably similar between fungi and insects melanization that highlight a functional importance for melanins in the evolution of life.
