Thermoactinomyces sacchari sp.nov., a Thermophilic Actinomycete Causing Bagassosis

SUMMARY: A new species of thermophilic monosporic actinomycete, isolated from mouldy sugar cane bagasse, is described as Thermoactinomyces sacchari sp.nov. It is distinguished from T. vulgaris Tsiklinsky by short tufted aerial mycelia that rapidly autolyse and are not always seen, by bearing spores on short sporophores, by its appearance on different culture media and by serological differences. Both species have heat-resistant spores containing dipicolinic acid and with the structure of bacterial endospores. A sufferer from bagassosis who inhaled extracts of T. sacchari developed symptoms characteristic of the disease.