• Journal of Life Science
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• v.6 no.4
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• pp.264-269
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• 1996

Monoclonal antibodies against the zoospores of Allomyces macrogynus were prepared using standard hybridoma technique. Mice were immunized either with the fixed zoospores or the zoospore proteins, and the production of the antibodies from the resulting hybridomas were screened by enzyme-linked immunosorbent assay (ELISA). Thirty hybridomas were initially identified ans six hybridomas were purified to the single cell clones. Culture supernatants from the hybridomas were tested for the effects on the growth of the germ tubes, and some of the hybridoma culture supernatants studied showed growth stimulatory effects.

• Journal of Microbiology
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• v.34 no.3
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• pp.220-224
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• 1996

Ultrastructural organization of encysting zoospores of Allomyces macrogynus was examined using the methods of cryofixation and freeze substitution. During enxcystment, obvious changes were observed at the surface of the plasma membrane and in the structure of gamma particles. Many multivesicular bodies associated with the plasma membrane were observed at early stages of encystment. After induction of encystment, vesicles were found within the gamma particles. These vesicles appeared to leave gamma particles after forming multivesicular bodies. This study suggests that the cell wall formation during encystment is mediated by the fusion of multivesicular bodies with the plasma membrane.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.243-247
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• 1998

Comparative analyses of intracellular biopterin contents and its biosynthetic enzymes were performed in Allomyces macrogynus. Biopterin content in fresh weight was 14-fold higher in mycelium than in zoospore. Enzyme activities of GTP cyclohydrolase I and 6-pyruvoyltetrahydropterin synthase in ammonium sulfate fractions were approximately 2-fold higher in mycelium. On the other hand, sepiapterin reductase (SR) activity was 10 fold higher in zoospore. Northern blot assay also demonstrated that SR transcript was abundant in zoospore. These results suggest a possible involvement of tetrahydrobiopterin in cellular differentiation of Allomyces macrogyllus as well as provide an experimental basis to elucidate the physiological function of SR in this organism.

• Journal of Microbiology
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• v.34 no.4
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• pp.374-378
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• 1996

In the aquatic fungus Allomyces macrogynus the effects of $Ca^{2+}$ and cAMP on the intracellular signal transduction of zoospore germination were studied using in vitro protein phosphorylation assay system. An endogenously phosphorylated protein (p50) having molecular weight of 50 kDa on SDS-PAGE was found in soluble fractions of both zoospore and mycelium. In zoospore extract, the endogenous phosphorylation of p50 was weak without any effectors, but was enhanced by $Ca^{2+}$ and even more by cAMP. Phosphorylation of the same protein in mycelial extract was high only in the absence of cAMP. Irrespective of the presence of $Ca^{2+}$ and cAMP, its phosphorylation was antagonistically suppressed in assay of combined zoospore and mycelial extracts. These results suggest that p50 is interconvertible in phosphorylation/dephosphorylation as a novel protein involved in germination of A. macrogynus. The antagonistic effect of cAMP to the phosphorylation of p50s from different developmental stages may be important in the regulation of cellular differentiation.

• Proceedings of the Microbiological Society of Korea Conference
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• 1997.04a
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• pp.51.2-51.2
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• 1997

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.203.1-203
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• 1997

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