Mucor racemosus is a member of the order Mucorales of the Zygomyceta. Although Mucor exhibits multiple morphologies, interest has focused on vegetative yeast-hyphal dimorphism. Part of the interest in Mucor dimorphism concerns their potential as etiological agents of disease. In healthy humans, Mucor rarely causes disease, but in the host compromised by immune deficiency, immune suppression, or a serious underlying disease, the incidence of Mucor infections is much higher. Although the yeast form of Mucor has been observed in human and animal tissue, invariably it is the hyphal form that is associated with disease and pathology (Rippon, 1982). Thus, there may be a very practical reason for understanding the process of dimorphism among Mucor, since from such knowledge may emerge improved chemotherapeutic procedures, not only for infections involving Mucor, but also for infections involving the other pathogenic dimorphic fungi. In addition to the clinical implication of Mucor dimorphism, in the past several years there has been growing interest in Mucor as a model system to investigate fundamental questions of the molecular biology of cellular morphogenesis. In particular, these studies have focused on differential gene expression during Mucor development and on the mechanisms that may serve to regulate such expression.
KeywordsPyruvate Kinase cAMP Level Catabolite Repression Fatty Acid Synthetase Hyphal Development
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