UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Production, Bioassay, and partial purification of erogens from Tremelia mesenterica Fr Reid, Ian Duncan

Abstract

A defined medium containing glucose, ammonium sulphate, thiamine, salts and microelements supports good growth of Tremella mesenterica Fr. 2259-7. A high concentration of microelements selectively slows growth in media containing amino acids. L- asparagine causes slow and abnormal growth. Conjugation hormones secreted by haploid cells of each mating type of T. mesenter ica induce the growth of conjugation tubes from cells of the other mating type. The conjugation hormones (erogens) from strain 2259-7 can be extracted from, aqueous solution with n-butanol, but not with less polar solvents. They are strongly adsorbed on activated charcoal, and on the polystyrene resin Porapak. The erogens are also adsorbed on both anion and cation exchange resins, partly by non-polar forces and partly by ionic forces. Ultrafiltration indicates that the molecular weight of the erogens is less than 750. Three active materials are separated by chromatography on silica gel columns with a gradient of water in ethanol, and two active components can be separated by thin layer chromatography. A quantitative bioassay for erogen activity has been developed, based on the fraction of cells which produce conjugation tubes. An incubation time of 12 to 18 hours, at 20°C, pH 5-5; and low cell density with a complex nitrogen source is optimal for conjugation tube production. The effect of compositon of the medium on production of erogens in 2259-7 cultures has been studied, and a defined medium giving high hormone yields has been selected. The erogens can be concentrated and partially purified from, cultures by foaming. Attempts to purify the erogens have been hampered by low recoveries of hormone activity. The erogens may be amino acids or short peptides with non-polar side chains.

Item Media

Item Citations and Data

Rights

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.