BIOL 134 Lecture 38: lecture 38 (12-2-16)
Document Summary
Fungal infection of the skin, hair, or fingernails. Dermatophytes = fungi that can cause cutaneous mycosis. Ringworm: even though this does not involve worms! Dermatophytes secrete keratinases that break down keratin into a digestible form. Hair and fingernails are mostly keratin as well. Grows best with some moisture, but able to get by with less moisture than bacteria. Avoids sloughing by digging mycelia into the skin. A(cid:374)thropophili(cid:272) (cid:894)(cid:862)people lo(cid:448)i(cid:374)g(cid:863)(cid:895) - passed from person to person. Estimated that 20% of the population has some form. Koh dissolves fragile human cells, leaves tough fungal cell walls intact. Thoroughly dry areas that may stay moist (between toes) Many antibiotics made use of differences between bacteria and eukaryotes. Most of these processes are the same between fungi and humans. For years, only drug available was amphotericin b. New, synthetic antifungal drugs have much less toxicity. Dermatophytes are unable to grow beneath the top layer of dead cells.
