Trichophyton mentagrophytes a keratinophilic fungus

Trichophyton mentagrophytes is a keratinophylic fungus belonging to a homogeneous group of fungi called the dermatophytes. The dermatophytes cause a variety of cutaneous infections in humans and animals. T. mentagrophytes has at least five different variants which make up the Trichophyton mentagrophytes complex. Two perfect states Arthroderma benhamiae and Arthroderma vanbreuseghemii have been ascribed for T. mentagrophytes. The organism has variable characteristics with anthropophilic form producing sparse aerial mycelium with numerous spores. The zoophilic isolate produces powdery or granular colonies. Microscopically the most consistent feature of T. mentagrophytes is the production of globose microaleuriospores arranged in grape-like clusters. T. mentagrophytes assimilates phosphorus, potassium, sodium and calcium. It utilizes methionine but is inhibited by folic acid. The organism has been recovered from a variety of sources such as soil, floor of swimming pools, hairs of wild boar, cats and dogs, farm animals, foot wears, shower stalls and from human toewebs without clinical lesions. T. mentagrophytes breaks down keratinous substrates by both chemical and mechanical ways. Five different keratinolytic enzymes from ten strains of T. mentagrophytes have been isolated. These enzymes are known to play a role in pathogenesis of infections caused by this organisms in both humans and animals.