Ascomycota of their hosts. Owing to their long evolutionary history, the Ascomycota have evolved the capacity to break down almost every organic substance. Unlike most organisms, they are able to use their own enzymes to digest plant biopolymers such as cellulose or lignin. Collagen, an abundant structural protein in animals, and keratin—a protein that forms hair and nails—, can also serve as food sources. Unusual examples include "Aureobasidium pullulans", which feeds on wall paint, and the kerosene fungus "Amorphotheca resinae", which feeds on aircraft fuel (causing occasional problems for the airline industry), and may sometimes block fuel pipes. Other species can
YqaJ protein domain YqaJ protein domain In molecular biology, the YqaJ refers to the YqaJ/K domain from the "skin" prophage of the bacterium, "Bacillus subtilis". This protein domain, often found in bacterial species, is actually of viral origin. The protein forms an oligomer and functions as an alkaline exonuclease, or in simpler terms, an enzyme that digests double-stranded DNA. It is a reaction which is dependent on Magnesium. It has a preference for 5'-phosphorylated DNA ends. It thus forms part of the two-component SynExo viral recombinase functional unit. The function of this protein domain is to digest DNA. Most viruses, inject their host