Increased glycogen storage in yeast results in less branched glycogen.
Glycogen is a branched polymer of glucose, synthesized as a reserve of both energy and carbon. The branched nature of glycogen is important for its function and polyglucosan bodies, particles that contain a glycogen-like polymer with reduced branching, are a feature of several disease states. The degree of glycogen branching is thought to be governed by the balance between glycogen synthesis and branching activities. However, there have been reports that the intrinsic properties of individual branching enzymes govern the degree of branching. To address the relationship between synthesis and branching more fully, we made use of the yeast Saccharomyces cerevisiae. The glycogen content of yeast cells was manipulated by using different growth conditions or by the introduction of specific mutations. Whenever glycogen storage was elevated, the polysaccharide formed was found to be less branched but normal branching could be restored by overexpression of branching enzyme.
Wilson
Wayne A
WA
Department of Biochemistry and Molecular Biology, Center for Diabetes Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Hughes
William E
WE
Tomamichel
Wendy
W
Roach
Peter J
PJ
D015061:1,4-alpha-Glucan Branching Enzyme / Q000378:metabolism; D006003:Glycogen / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
D006003:Glycogen; D015061:1,4-alpha-Glucan Branching Enzyme