The glucan components of the cell wall of baker's yeast (Saccharomyces cerevisiae) considered in relation to its ultrastructure.
1. Commercial pressed baker's yeast, and cell walls prepared from it, were extracted in various ways and the products examined by a number of techniques, including infrared spectroscopy and electron microscopy. 2. The glucan components of the walls cannot be extracted from intact yeast cells by 3% (w/v) sodium hydroxide at 75 degrees , but at least one-third of the glucan of cell wall preparations is dissolved under these conditions, and more will dissolve after ultrasonic treatment. 3. If intact cells are given a preliminary treatment with acid the wall glucans dissolve in dilute aqueous alkali. 4. Acid conditions as mild as sodium acetate buffer, pH5.0, for 3hr. at 75 degrees are sufficient for this preliminary treatment; the glucan then dissolves in 3% sodium hydroxide at 75 degrees leaving a very small residue, which contains chitin and about 1% of the initial glucan of the wall. Dissolution is hindered by exclusion of air, or by a preliminary reduction with sodium borohydride, suggesting that some degradation of the glucan by alkali is taking place. 5. After treatment with 0.5m-acetic acid for 24hr. at 90 degrees the glucan dissolves slowly at room temperature in 3% sodium hydroxide, or in dimethyl sulphoxide. The extraction with acetic acid removes glycogen and a predominantly beta-(1-->6)-linked glucan (not hitherto recognized as a component of baker's yeast), but none of the beta-(1-->3)-glucan, which remains water-insoluble. 6. Without treatment with acid, the glucan is not significantly soluble in dimethyl sulphoxide, but can be induced to dissolve by ultrasonic treatment. 7. These results are interpreted by postulating the presence of an enclosing membrane, composed of chitin and glucan, that when intact acts as a semipermeable membrane preventing the escape of the alkali- and dimethyl sulphoxide-soluble fraction of the glucan. Mild acid treatments damage this membrane, and ultrasonic and ballistic disintegration disrupt it. 8. Some support for this hypothesis is given by the effects of certain enzyme preparations, which have been found to render a substantial part of the glucan extractable by dimethyl sulphoxide.
D000085:Acetates; D002021:Buffers; D002462:Cell Membrane; D002473:Cell Wall / Q000032:analysis*; D002686:Chitin / Q000032:analysis; D004121:Dimethyl Sulfoxide; D007259:Infrared Rays; D008854:Microscopy, Electron; D011134:Polysaccharides / Q000032:analysis*; D012440:Saccharomyces / Q000032:analysis* / Q000166:cytology*; D012972:Sodium Hydroxide; D013057:Spectrum Analysis; D014465:Ultrasonics
D000085:Acetates; D002021:Buffers; D011134:Polysaccharides; D002686:Chitin; D012972:Sodium Hydroxide; D004121:Dimethyl Sulfoxide
Bacteriol Rev. 1963 Sep;27:305-24
14063857
Biochem J. 1937 Jan;31(1):72-80
16746315
Biochim Biophys Acta. 1968 May;158(2):313-5
5654602
Exp Cell Res. 1960 Jun;20:28-42
14425237
Biochem J. 1962 May;83:325-31
13882340
Biochem J. 1965 Sep;96(3):651-8
5862404
Biochem J. 1952 May;51(2):232-6
14944578
J Biol Chem. 1959 Sep;234:2281-5
14408682
Biochim Biophys Acta. 1953 Aug;11(4):471-9
13105668
Biochem J. 1967 Oct;105(1):189-203
6056621
FEBS Lett. 1968 Jul;1(1):67-68
11945254
Biochem J. 1959 Nov;73:507-14
13795624
Biochem J. 1952 Jan;50(3):298-303
14915949
J Gen Microbiol. 1966 Sep;44(3):329-41
5971383
Biochim Biophys Acta. 1953 Mar;10(3):477-8
13059006
Biochem J. 1968 Dec;110(3):34P-35P
5701657
J Gen Microbiol. 1955 Jun;12(3):473-7
14392302
Biochem J. 1968 Sep;109(3):419-32
5685868
Biochem J. 1956 May;63(1):23-33
13315242
Biochem J. 1953 Feb;53(3):348-52
13032077
Biochim Biophys Acta. 1962 Mar 12;57:525-33
13913905
Annu Rev Microbiol. 1963;17:15-30
14145300
J Biophys Biochem Cytol. 1961 Mar;9:689-99
13781662
Antonie Van Leeuwenhoek. 1968;34(2):173-82
5301324
Antonie Van Leeuwenhoek. 1967;33(2):159-65
5298433
Science. 1956 Aug 10;124(3215):272-3
13351642
J Gen Microbiol. 1968 Sep;53(2):163-9
5721806
J Bacteriol. 1955 Oct;70(4):427-34
13263312
J Bacteriol. 1968 Jul;96(1):270-1
4874311
Biochem Soc Symp. 1963;22:105-25
13938986
Biochem J. 1960 Apr;75:12-7
14411049