ISSN:
1432-072X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The chemical composition of cell walls from choline-less Torulopsis pintolopesii grown with choline or with methionine was studied. Methioninegrown cells synthesized a weakened cell wall compared to normal choline-grown yeast. The ethylenediamine fractionation procedure yielded three fractions—A, B, and C—with different solubilities. Glucose and mannose were detected in hydrolysed unfractionated cell walls from yeasts grown under both conditions as well as in all fractions. Glucose content was greater in fractions B and C from methioninegrown cells; the mannose content was about the same. Walls from choline-grown cells (W c ) had 25% more protein than walls from methionine-grown cells (W m ). The amino acid composition of the proteins of W c and W m was not qualitatively altered. Seventeen amino acids were identified; glutamic and aspartic acids and valine predominated. W c had 3.5 times more lipid than W m . The amount of phosphorus was the same. Yeasts grown on methionine synthesized more ergosterol than choline-grown cells. The rate of formation of spheroplasts was higher in methionine-grown cells. Rates of incorporation of adenine, glutamic acid, and uracil were similar in cells grown on methionine or choline; incorporation of phenylalanine and tyrosine was depressed in methionine-grown cells.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00425242
