Ascus ofHypocrea virens with eight two-celled ascospores
Ascomycota is aphylum offungi (kingdom Fungi) which can live in practically every environment, from freshwater habitats to deserts and forests.[2] It is currently has over 64000 species which makes it the largestphylum of fungi.[3]
Members are commonly known as thesac fungi, due to the phylum having an ascus which is a sac like structure. Within this structure there are eight ascospores which are the sexual organ for ascomycetes. The ascospores get released by the ascus under humid conditions into the air where they can land on objects and spread the fungi.[4] The ascus defines the group and distinguishes it from other fungi.
There are currently three accepted classes in Ascomycota which areSaccharomycotina,Taphrinomycotina, andPezizomycotina. Saccharomycotina mostly contains species which are single-celled (unicellular) like baker’s yeast (the yeasts that are commonly used in baking and result in the product rising) and Candida (the yeasts which cause the most fungal infections in the world). The species in Saccharomycotina reproduce bybudding which is when an organism reproduces by forming a ‘bud’, this bud develops into a full organism. Taphrinomycotina are plant parasites that can has both a unicellular state and a filamentous (long, thread like structure) state when infecting plants. In their structure they do have an ascus but not ascomata. The largest subphylum in Ascomycetes is Pezizomycotina which contains all the species with fruiting bodies (except forNeolecta). Some examples members of the subphylum are cup fungi and truffles.[3] These fungi reproduce bybinary fission which is when the bacterium divides into two (or more) and each part regenerates to become a new cell which resembles the original cell.[5]
Ascomycetes are extremely useful to humans as the have multiple uses in different fields such asfermentation with bread, alcohol and cheese and producing compounds which can be used in antibiotics and other medicine.[3] An example is thegenusPennicillium. Some species of the genus can producepenicillin which can stop the growth or kill certain bacteria when it is used in antibiotics. But also, there are other species of Penicillium are import in producing certain types of cheese.[6] However, this phylum can also be very harmful to not only humans but also plants and other animals. Members are known to cause skin infections in humans, Dutch elm disease in trees and rice blast in oryza.[3]
