THE POLYSACCHARIDES OFCRYPTOCOCCUS LAURENTII(NRRL Y-1401): PART I

Abstract

The extracellular polysaccharides produced by Cryptococczrs lazrrenlii have been isolated and shown to consist of (A) a n acidic polysaccharide containing D-mannose, D-xylose, and D-glucuronic acid; ( B ) a neutral polysaccharide containing D-glucose only.Preliminary structural studies on the acidic material suggest that it consists of a mannosecontaining backbone with xylose and glucuronic acid as end groups, \vhile the glucan contains 1 -,3 3, 1 --t 4, 1 --t 2, and (or) 1 --t 6 linked residues. INTRODUCTION l/Iucli is l t n o~~~n about the origin of sugars fouiid in ho~~~opolysaccharides (1-11). On the other halid the origin of sugars in heteropolysaccharides has not been investigated to any great extent (12, 13).As part of a program for iiivestigatiiig the biosynthesis of monosaccliarides found in heteropolysaccl~arides, we have studied the extracellular polysaccharide produced by the yeast orgallisill Cryptococc~ls lar~rentii.This organism, 1;indly supplied by the United States Department of Agriculture, Peoria, Illinois, was chosen because it produced high yields of polysaccharides froin a wide variety of sugar substances.Cryfltococc~~s laz~rentii \\.as grown 011 an unbuffered casaiiiiiio acids -salts medium n~i t h glucose as the main carbon source (14). An acidic and a neutral polysaccharide were isolated by the follo\\~ing procedure, which was considered unlil<ely to cause degradation of the polysaccliarides. The cell-free solution was dialyzed and then passed through an ion exchange column to give a clear, light brown viscous solution. After the solution was concentrated, the polysaccharides were precipitated with ethanol and Ilad [a]D +27O. Chrolnatographic examination of the acid hydrolyzate slio~ved sugars which moved a t rates corresponding to mannose, xylose, glucuronic acid, and glucose. The sugars were obtained crystalline or as crystalline derivatives and were sholvn to be D-mannose, D-sylose, D-glucose, and D-glucuronic acid. The crude polysaccharide showed two pealts on electrophoresis in a veronal buffer. On addition of a n aqueous solutioli of 'cetavlon' (cetyltrimethyl-ammonium bromide) to an aqueous solution of the polysaccharide an illsoluble cetyltrimethyl-ammoniui~~ salt of an acidic polysaccharide was precipitated. 'This salt was dissolved in 10yo aqueous sodium chloride solutioil and the sodium salt of the acidic polysaccharide was precipitated in ethanol. Chroiiiatographic exaininatioil of the acid hydrolyzate of this material shelved mannose, xylose, and glucuronic acid to be present. Electrophoresis ill veronal and borate buffers showed a single peali: glass paper electrophoresis (17) showed a single spot. Further attelilpts a t fractioilatioil failed to give any separation. The supernatant from the cetyltrimethyl-aniinoiiium precipitate was concentrated and added to ethanol. l4ainly glucose and traces of mannose, xylose, and glucuronic acid were detected in the precipitated inaterial (chromatography).The acidic polysaccharide had [aID 4-21"; the molar ratio of mannose to x...

A novel pentosylmannan arising from the yeast Trichosporon cutaneum

“…126. 5 The product was treated a t 100' for 18 h with aqueous barium hydroxide, and the solution was neutralized (COz), filtered, and evaporated. On a paper chromatogram (solvent, n-butanol-ethanolwater (40: 11: 19 v/v/v) ; spray, amtnoniacal silver nitrate) a spot running a t the same rate as glycerol was detected.…”

“…(2,3) and certain Rhodotorula spp. (4), which also produce a heteropolymer consisting of glucuronic acid, xylose, and mannose units (5,6). I t was therefore of interest to investigate other possible polysaccharides formed by Trichosporon cutaneurn.…”

Some structural features of the heteropolysaccharides of Candida bogoriensis

“…The main heteropolyn~er ( z 80%) has an a-D-(l+3)-linked lnannan main-chain as shown by s~~ccessivc Smith degradations. Partial hydrolysis of the hcteropoly~liers provided several methylpentose-containing oligosaccharide fragments corresponding to possible sidechain components.Canadian Journal of Chemistry, 46, 3407 (1968) Information on the nature of extracellular and been useful as an aid in classification of t h e parent intracellular polysaccharides of yeasts has often organisms (1)(2)(3)(4)(5)(6)(7)(8). These investigations have now been extended to include other yeasts of the genus 'Issued as NRCC No.…”

“…Canadian Journal of Chemistry, 46, 3407 (1968) Information on the nature of extracellular and been useful as an aid in classification of t h e parent intracellular polysaccharides of yeasts has often organisms (1)(2)(3)(4)(5)(6)(7)(8). These investigations have now been extended to include other yeasts of the genus 'Issued as NRCC No.…”

Estimated Molecular Weight of Amylose From the Yeast Rhodotorula Peneaus

“…Abercrombie et a/. (4) investigated the exocellular polysaccharide of Cr. lazirentii grown a t pH 7, and isolated a heteropolymer containing inannose, xylose, and glucuronic acid.…”