A Β-glucan endo-hydrolase fromSchizosaccharomyces pombe and its role in cell wall growth

Abstract

BARRAS, D. R. 1972. A ~-glucan endo-hydrolase from Schizosaccharomyces pombe and its role in cell wall growth. Antonie van Leeuwenhoek 38: 65-80.A [3-glucan hydrolase showing a marked specificity for 13-1,3-glucosidic linkages was found to be closely associated with the cell wall of the fission yeast Schizosaccharomyces pombe. Intact log-phase cells showed 40 ~o of the enzyme activity measured in the cell homogenate. Cellular enzyme activity reached a maximum during the logarithmic growth phase and decreased sharply in the stationary phase. The possible role of the enzyme in cell wall extension is discussed.

Molecular Aspects of Yeast Morphogenesis

“…The "glucanase vesicles" that might participate in these processes have been mentioned in the section on budding. In addition, several glucanases are accumulated in the cell walls (11,57,62) and excreted in the growth medium by cells (1,57) and protoplasts (21,57). These enzymes may be responsible for the lysis observed in the presence of 2-deoxyglucose, when polysaccharide syn thesis is inhibited and therefore the normal balance between breakage of old bonds and fo rmation of new ones is disrupted.…”

Secretion of β‐glucanase by Saccharomyces cerevisiae protoplasts

“…Several lines of evidence indicate that /3glucanases may play an important role in budding, conjugation and cell-wall extention in yeast [l- .5] . In some cases, P-glucanases were found to be associated with yeastcell wall [4,5] or released into the growth medium by intact yeast cells [6] . It is also known that yeast protoplasts, under appropriate conditions, synthesize and secrete most, if not all, of the cell-wall components [7,8] .…”

Protoplast Transformation for Genome Manipulation in Fungi

“…Among hydrolases identifi ed to date, chitinases, glucanases, and transglycosylases are found to be responsible for breaking and reforming of bonds within and between polymers, leading to re-modeling of the cell wall during growth and morphogenesis (Adams 2004 ;Lesage and Bussey 2006 ). The presence of these polysaccharide hydrolases in fungi indicates an autolytic activity in the fungal cell wall (Barras 1972 ;Fevre 1977 ;Fleet and Phaff 1974 ). This autolytic function involves not only cell wall weakening during growth and other morphogenetic processes (Adams 2004 ;Lesage and Bussey 2006 ).…”