The fruit body development of wood-rotting fungi is still unexplained. The hormones or external signal molecules, even though they are omnipresent in nature, have been not identified. However, in our trials to find chemical substances that effectively stimulate the fruiting of Pleurotus ostreatus (oyster mushroom) under laboratory conditions, we found that the sucrose ester of fatty acids (SE) and triterpenoid glycoside (saponin) could induce fruiting on P. ostreatus. The fruiting inducing activities of synthetic triterpenoid glycoside analogs correlated with the number of sugars attached to the aglycon. Additionally, the synthetic series of 3-O-alkyl-D-glucose could also induce the fruit bodies in P. ostreatus where the activities correlated with the alkyl chain lengths. From the common structure of these substances, we hypothesized that a sugar linked to a hydrophobic compounds is essential to the fruit body development of P. ostreatus.1),2)
If such compounds mimic the true fruiting signals, they might be glycoconjugate generally known to be involved in cell signaling and differentiation3). In this conference, our further trials to find chemical substances which stimulate fruiting at the significantly low concentration (less than 0.001% in medium) will be presented. For this purpose, the novel compounds library including a synthetic glyceroglycolipid analog, i.e. the series of 1,2-di-O-acyl-3-O-(b-D-glucopyranosyl (or b-D-cellobiosyl))-glycerol with different acyl chain lengths and commercially available glucosylceramides are now under construction. The screening of the fruiting inducing active compounds and the structure-activity relationship will be discussed.
Reference
1) Magae Y., Nishimura T., Ohara S. (2005) Mycol. Res.109, 374-376, 2) Magae Y., Nishimura T., Ohara S. (2009) Current Chemical Biology 3, 231-237, 3) Kawai G. and Ikeda Y. (1983) BBA, 719, 612-618.
Acknowledgment
This work was supported by JSPS KAKENHI Grant Numbers 24658160
