An Electron Microscopy Study of Keratin Degradation by the Fungus Microsporum Gypseum In Vitro
April 2009
in “
Mycoses
”
keratin Microsporum gypseum transmission electron microscopy enzymatic degradation hair cuticle keratinization cystine exocuticle cell membrane complex macrofibril bundles microfibrils matrix of hard keratin hair protein fungal infection electron microscope enzyme breakdown hair surface protein hardening amino acid outer layer cell boundary fiber bundles hair fibers hard hair protein
TLDR Microsporum gypseum fungus breaks down keratin in hair by digesting it enzymatically, starting with less keratinized parts.
The study used transmission electron microscopy to investigate how the fungus Microsporum gypseum degrades keratin in human hair in vitro. Initially, the fungus grew between cells, but later it was found inside the cells. The degradation process was enzymatic, with mechanical effects observed only in the hair cuticle. The sequence of degradation correlated with the degree of keratinization and cystine content. Nonkeratinous components and cytoplasmic remnants in the cuticle were digested first, while the exocuticle and its A-layer were more resistant. In the cortex, the cell membrane complex and cytoplasmic residues were also digested first, with macrofibril bundles disintegrating from both the surface and center. The fungus digested both the microfibrils and matrix of "hard" keratin, although matrix remnants persisted slightly longer in the final degradation phases.
