The Isolation of, and Cytodifferentiation of a Mucor species as Affected by Nitrogen Source and Elevated Temperature
Vegetative differentiation leading to dimorphic switching by filamentous microorganisms has drawn intense attention from scientists for a long time because of the central role played in the attempt to understand life processes, as well as the serious impacts exhibited in medicine, agriculture and industrial processes. A mucoraceous isolate, Mucor manihotis (tentative), from an agricultural niche was found to exhibit dimorphism in minimal medium; induced were thalloarthric-, holothallic-, holoblastic conidia as well as polar budding globose yeast cells when supplemented with ammonium sulphate or peptone as nitrogen source. Boxplot construction showed that peptone enhanced growth, but elevated temperature had profound morphogenetic effect as ovoidal and spindle shaped yeast cells additionally induced. The simultaneous induction of different cell wall structures necessitated further examination of the early growth stage. The process of differentiation that resulted in yeast ontogeny rooted in cytodifferentiation, involving vanishing cell wall of germ cells and then sequentially generated cryptic forms, only membrane bound, until reappearance of cell wall in nascent yeast, which at maturity became polar budding. Simultaneous induction of wall-less entities on the one hand, and complex walled entities on the other prompted a re-examination of cell wall geometry as hinge for dimorphic switching. It was suggested that more attention should be given to cytoplasmic membrane as default candidate.
