Summary
In contrast to all filamentous fungi examined to date, vegetative hyphae ofAllomyces macrogynus, whether extending or not, produced an outward flow of positive electrical current, at a maximum of 0.16 μA cm−2 around 40 μm behind the apex, as measured with a vibrating probe. Inward currents of up to 0.55 μA cm−2 were recorded around the rhizoids. Increases in outward current were observed in hyphae pre-grown under oxygen deficiency and then allowed to widen backwards to the hyphal base in sufficient oxygen. When spores were germinated in an applied electrical field they produced rhizoids predominantly towards the anode. Hyphae were produced initially towards the cathode but later bent around towards the anode. Experiments with a range of chemicals provided no evidence for the involvement of calcium in vegetative growth and development inA. macrogynus. Polyoxin and nikkomycin, inhibitors of chitin synthesis, had no effect on swimming zoospores, but inhibited wall formation of cysts, rhizoids and forward and backward growing hyphae.
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Youatt, J., Gow, N.A.R. & Gooday, G.W. Bioelectric and biosynthetic aspects of cell polarity inAllomyces macrogynus . Protoplasma 146, 118–126 (1988). https://doi.org/10.1007/BF01405920
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DOI: https://doi.org/10.1007/BF01405920