There's simply no way that this type of fungus could absorb enough radiation simply because it's not dense enough.<p>If you want to absorb radiation you have to block it which means it has to come into contact with matter.<p>The only way you can do this is to have either a smaller volumetric amount of something that's dense (lead, gold, uranium, etc) or a LARGE amount of something less dense (water, concrete, etc).<p>If you're just talking about an organic organism, sure, it can use the radiation BUT you'd need to have a MASSIVE amount of it in terms of volume and weight.<p>Simply put, the fungus itself is sparse when looking at it from a subatomic perspective. Most of the radiation passes right through it.