ИСТИНА

Microbial endocrinology is a recently developed interdisciplimary field dealing with hormones and neuromediators in microorganisms, including fungi, and emphasizing the role of these substances in microbiota/mycobiota-host interaction. For instance, Neurospora crassa was found to produce insulin that regulates glucose metabolism in this fungus [1]. Relatively few data have been obtained on the role of biogenic amines, an important group of neuromediators, in the kingdom of fungi, and this was the subject of our work. Methods. The yeast Saccharomyces cerevisiae and mycelial fungi (Cunninghamella japonica and Aspergillus oryzae) were grown on agar-containing Saboureaud's and Czapek's medium, respectively. The media were supplemented with the biogenic amines serotonin (5-HT), norepinephrine (NE), and dopamine (DA) at concentrations of 0.1-100 μM (an equal volume of water was added to the control media). The growth of the fungi was monitored by counting cell number per field (in the yeast culture) or measuring hypha elongation (in the mycelial fungi). Results. Cell proliferation in S. cerevisiae was stimulated by DA (an ~8-fold stimulation was attained with 1μM DA) and, to a lesser extent, by 5-HT, but not by NE. All the amines exerted no significant influence on the linear growth of the hyphae of C. japonica and A. oryzae. Conclusions. The results militate against the hypothesis that biogenic amines are widespread regulators/signals in the kingdom of fungi. The data seem to be consistent with the suggestion that their effects are only characteristic of fungal species that intensely interact with multicellular host organisms. The stimulatory effect of DA and 5-HT on the yeast is presumably due to the fact that its biofilms, in nature, grow on grape and plum plants and might be evolutionarily adapted to the biogenic amines released by them [2]. 1. Lyte, M. (1993). The role of microbial endocrinology in infectious disease. J. Endocrinol., 137, 343-345. 2. Roshchina, V. V. (2010). Evolutionary considerations of neurotransmitters in microbial, plant, and animal cells. In: Microbial Endocrinology: Interkingdom Signaling in Infectious Disease and Health. Eds. M. Lyte & P. P. E. Freestone. New York: Springer, pp. 17–52.