| Notes | 'Annotations(1/26/2024, 4:14:56 PM)\n“First, melanized fungal species colonize the walls of the damaged reactor at Chernobyl where they are exposed to a high constant radiation field (12). Second, melanized fungal species are found in the so-called reactor cooling pool water. This water circulates through the nuclear reactor core for cooling purposes and is extremely radioactive. These pools comprise large amounts of fungi, cocci, Gram-positive rods, and some Gram-negative rods.” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 2)“However, many fungi, especially melanized ones are very radioresistant, with LD10 values approaching or exceeding 1 kGy (Table 1). This radioresistance of fungi is not widely appreciated and should be taken into consideration when gamma radiation is used for sterilization of food or medical supplies” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 2)“The authors concluded that both beta and gamma radiation promoted directional growth of fungi from contaminated and clean areas towards the sources of ionizing radiation.” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 3)“They observed that radiation promoted spore germination in species from contaminated regions, which they called “radiostimulation”. Contrary to their previous results (17) they observed the “radiostimulation” only for the species from contaminated regions but not for isolates from the clean areas.” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 3)“Fungal contamination poses certain threats to the well-being of the crew not only because some of those fungi are potential human pathogens but also because fungi possess powerful enzymatic systems and secrete various metabolites capable of degrading structural materials inside the spacecraft – from polymers to various alloys” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 3)“The electron-microscopy investigation of Aspergillus versicolor and Penicillum expansum exposed to open space conditions for 7 months revealed many morphological changes, which apparently allowed those fungi to survive. For example, the polysaccharide capsule and melanin layer in P. expansum were significantly increased in comparison with control samples, as well the numbers of mitochondria and vacuoles in spaceexposed fungi were much higher than in controls” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 4)“we hypothesized that radiation could change the electronic properties of melanin, such that the pigment could function in energy transduction and that this might enhance the growth of melanized fungi” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 4)“ionizing irradiation changed the electron spin resonance (ESR) signal of melanin, consistent with changes in electronic structure (25). Irradiated melanin manifested a 4-fold increase in its capacity to reduce NADH relative to non-irradiated melanin” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 4)“The interaction with ionizing radiation was studied for three fungal species Cryptococcus neoformans which can be grown in both melanized and non-melanized forms depending on the presence of exogenous substrate, and two intrinsically melanized species Wangiella dermatitidis and Cladosporium sphaerospermum with the latter being one of the predominant species inhabiting the destroyed reactor in Chernobyl.” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 4)“radiation enhanced the growth of melanized C. sphaerospermum cells under limited nutrients conditions. The observations that melanized fungal cells manifested increased growth relative to non-melanized cells after exposure to ionizing radiation raised the intriguing possibility that melanin can function in energy capture and utilization” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 4)“Apart from a role in energy transduction, melanin appears to have significant radioprotective properties. Non-melanized C. neoformans and Histoplasma capsulatum are highly resistant to radiation but the presence of melanin further enhanced survival at higher doses” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 5)“We concluded that melanin protected fungi against ionizing radiation and its radioprotective properties were a function of its chemical composition, free radical quenching and spherical spatial arrangement” (Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 5)(Dadachova, Ekaterina and Casadevall, Arturo, 2009, p. 6) Definitely seems like melanized mushrooms will be better suited to our design goals, but do they need to come from a pre-irradiated growth environment to be more efficient?\n\n - AlexanderSE'
'Read\n - AlexanderSE'
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