Localization of some phosphatases in yeast

Abstract

en studied in yeast cell.~ that were: either fragmented by shaking intact cells with gta~,; heads ,~r by" [r~-potonic r,r isotonic disruption of protoplasts prepared fr,~m intact cPIIx. z. The non-sp~-ific acid pho~ph,tta_~t, with ontirrmm activity at pH between 3 and 4 wa.~ shown to ~mcur in the cell wall of commercial baker's yea_~t. As s,,;ne substrates of the enzyme can only enter that part of the cell vtflume corresponding to the cell wall and the act :vity is not increased by frt'Pzing and thawing the yeast, it was concluded that all the enzyme ix located here. 3. The highly specific a-glyccrophospi~tl~t-~, i~ entirely present in the unstractured c vtopla.sm of a i7-h culture of Saccharottu'ces carlxbergensis (No. 74}. 4. S. carlsbergensis ~No. 74) contains ~mlv one non-specific alkaline phospl~atasc. The distribution depends ut~m tl|t~ age of the culture: In ,t culture aged 17 h twothirds of the enzyme is bound to particles sedimenting from 3900 × g to roo ooo :~" g. and one-third is s~luble. In a culture ;tgttd 24 h 7o-85'.'.,~ of the enzyme is fouml in the soluble fraction, and only a small amount ix p,..ticle bound.

Purification and Characterization of Two Isoenzymes of DL-Glycerol-3-phosphatase from Saccharomyces cerevisiae

“…4 and 7). As indicated from subcellular fractionation of lysed spheroplasts, this activity has its main location in the cytosol (33,34). The narrow substrate specificity of the DL-glycerol-3-phosphatase conforms with its location in the cytosol, where a strict specificity would be essential to avoid interference with the plethora of phosphorylated metabolites in the metabolic network.…”

Location and Properties of an Esterase Activity in Saccharomyces cerevisiae

“…I . I) was assayed by using I-naphthyl acetate as substrate at pH 6.5 by the procedure described by Wheeler, Coleman & Finean (1972). Leucine aminopeptidase activity (EC.…”

Effect of Inositol-deficiency on Phosphatases of the Inositol-exacting Yeast,Saccharomyces cerevisiaeA-21-20

“…As shown in Table I, the cytoplasmic phosphatase is attributed to alkaline phosphatase, and the peripheral phosphatase is attributed to acid phosphatase, which are the same results as reported by Tonino and Steyn-Parve. 3 ) Therefore, these results lead us to consider that in inositol deficiency the cellular structure turned to be abnormal, as reported already,1,6,7) and that pNPP penetrated more easily into the cells or reached more easily to the phosphatases in the peripheral area. There is a possibility that the alkaline phosphatase moved to the peripheral area of the cell envelope or the masked enzyme (nonrepressible acid phosphatase) in the structure unmasked due to inositol-deficiency-induced abnormal structure (Table VI) and that pNPP may be able to reach to the phosphatase protein more readily.…”

“…In the case of direct determination by using intact cells, the cells from 0.1-0.5 ml of culture (ODS50nm 0.3-0.4) were suspended in MjlOO or MjlO Acetic acid-Na acetate buffer (pH [2][3][4][5][6] or Tris-HCl buffer (pH 7 -9) and Na 2 C0 3 -NaHC0 3 (pH 10-12) with 0.85% NaCI and 6-24.3 mM MgCI 2 , and the substrate was para-nitro-phenylphosphate (p NPP), which was used at the final concentration of 1-9 mgjml after 5 min preincubation at 30°C. The total volume was 1.0 ml.…”