Introduction to mycology.docx

Mycology is the study of fungus. Mycoses is fungal infection. Kingdom of fungi Domain: Eukarya Can be either unicellular or multicellular. Heterotrophic Needs oxygen to survive. Stain gram-positive. Cell wall made of chitin. Cell wall Has a chitin layer. Has glycoproteins The unique features of the...

Mycology is the study of fungus. Mycoses is fungal infection. Kingdom of fungi Domain: Eukarya Can be either unicellular or multicellular. Heterotrophic Needs oxygen to survive. Stain gram-positive. Cell wall made of chitin. Cell wall Has a chitin layer. Has glycoproteins The unique features of the fungus cell wall are: The β-1,3 glucan cross overs. The chitin cell wall. The Ascomycota phylum of kingdom fungi. 3 major subdivisions Saccharomycotina- unicellular yeast which reproduce by asexual budding (parent nucleus splits and migrates into the daughter cell) Cell wall made of chitin. Taphrinomycotina- multicellular hyphae which reproduces by sexual spores. Pezizomycotina- multicellular hypae which reproduces by sexual fission or asexual spores. What type of infections can they cause? Saccharomycotina Most common infection caused opportunistic pathogen Candida albicans. It doesn’t cause any harm unless it overgrows. Oral thrush Overgrowth of C.albicans on the tongue. White spots are seen down the throat. Vaginal thrush Overgrowth of C.albicans in the vaginal tract. Thick white discharge. Painful urination Common in people with IUD’s. Candida albicans can be isolated from blood cultures. Symptoms include. Fever and chills Skin rash Low blood pressure Abdominal pain Headaches. Muscle aches. Diagnosis test Sabouraud agar is used for fungi infections only. Agar dish should be tapped up. KOH test Scrape a colony onto a slide and add few drops of KOH and heat to speed up reaction. Most rapid Germ tube test (GTT) Used to differentiate candida albicans from other yeasts. Pezizomycotina Can reproduce via asexual and sexual. It causes illnesses such as aspergillosis (lung infection) and dermatophytosis (ringworm and athletes’ foot). Athletes foot White cracked painful skin between the toes. Caused by T-rubrum. Can be tested by lactophenol cotton blue staining or SAB agar. Treatment is foot creams. Aspergillosis Symptoms include shortness of breath and coughing mucus. Caused by aspergillus fumigatus. Can be tested by SAB agar. Forms black spot-on agar. Treated by antifungal tablets