The use of morphological and cell wall chemical markers in the identification of Streptomyces species associated with Actinomycetoma

Abstract

Most aerobic, filamentous, spore-forming actinomycetes are saprophytes but some are considered pathogens of humans and animals, notable examples are the causal agents of mycetoma. The present study aimed to identify Streptomyces spp. isolated from actinomycetoma cases in Sudan by examining some morphological traits and analyzing the cell wall composition. Nineteen Streptomyces strains isolated from purulent materials of patients with mycetoma (human) or fistulous withers (donkeys) were included in the study. Isolates were tentatively identified as Streptomyces species based on morphological and cultural characteristics. Cell wall analysis of isolates yielded LLdiaminopimelic
acid (LL-DAP) which authenticates that the isolates are members of genus Streptomyces. The isolates, though they are Streptomyces, but are variable phenotypes. The study concluded that using few selected criteria, as above, would allow identification of unknown actinomycetoma agent to the genus level. The study also assumes that apparently limitless, numbers of saprophytic Streptomyces enter human or animal skin tissue causing actinomycetoma and perhaps other complications in man and animals.

KEYWORDS: Actinomycetoma, Streptomyces species, Madura foot, Sudan