Article

Localization of trehalase in vacuoles and of trehalose in the cytosol of yeast (Saccharomyces cerevisiae).

Institut für Allgemeine Botanik der ETH
Archives of Microbiology (impact factor: 1.43). 07/1982; 131(4):298-301. DOI:10.1007/BF00411175 pp.298-301
Source: PubMed

ABSTRACT Protoplasts of Saccharomyces cerevisiae synthesized and degraded trehalose when they were incubated in a medium containing traces of glucose and acetate. Such protoplasts were gently lyzed by the polybase method and a particulate and soluble fraction was prepared. Trehalose was found in the soluble fraction and the trehalase activity mostly in the particulate fraction which also contained the vacuoles besides other cell organelles. Upon purification of the vacuoles, by density gradient centrifugation, the specific activity of trehalase increased parallel to the specific content of vacuolar markers. This indicates that trehalose is located in the cytosol and trehalase in the vacuole. It is suggested that trehalose, in addition to its role as a reserve may also function as a protective agent to maintain the cytosolic structure under conditions of stress.

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Keywords

cell organelles
 
degraded trehalose
 
density gradient centrifugation
 
particulate
 
particulate fraction
 
polybase method
 
protective agent
 
Protoplasts
 
Saccharomyces cerevisiae synthesized
 
soluble fraction
 
specific activity
 
specific content
 
traces
 
trehalase
 
trehalase activity
 
Trehalose
 
vacuolar markers