WEIMBERG R, ORTON W L
J Bacteriol. 1965 Mar;89(3):740-7. doi: 10.1128/jb.89.3.740-747.1965.
Weimberg, Ralph (Northern Regional Research Laboratory, Peoria, Ill.), and William L. Orton. Synthesis and breakdown of the polyphosphate fraction and acid phosphomonoesterase of Saccharomyces mellis and their locations in the cell. J. Bacteriol. 89:740-747. 1965.-The conditions for accumulation of polyphosphate in cells of Saccharomyces mellis differ in several respects from those for acid phosphomonoesterase biosynthesis and maintenance. Polyphosphate can be synthesized or degraded in vivo by resting cells, provided an energy source is present. Experiments with growing cells indicate that the enzyme systems involved in the metabolism of the polyphosphate fraction are constitutive, since cells respond immediately to changes in the level of inorganic phosphate in the external medium. There is no change in the acid phosphatase level in either resting cells or in cells in the lag phase of growth. Enzyme formation or breakdown occurs only in cells that are exponentially dividing. Enzyme is lost rapidly from derepressed cells when they are transferred to a phosphate-rich medium, falling to a very low value by the time the cell mass had doubled. Protoplasts of repressed cells were prepared to determine the location of ortho- and polyphosphates in the cell. Previous studies have shown that phosphomonoesterase is released as a soluble enzyme when derepressed cells become protoplasts. Unlike phosphomonoesterase in derepressed cells, the two phosphate fractions in repressed cells are still attached to the protoplast after the cell wall has been digested and are eluted only when the protoplast structure is lysed in cold water. However, it is also possible to extract a part of the two phosphate fractions from intact cells in the absence of snail gut extract by osmotic shock if the cells are first suspended in a solution of high salt concentration. This treatment with salt does not affect viability. These results do not permit a definite conclusion concerning the location of ortho- and polyphosphates in the cell, other than that they are associated with the protoplast and thus occupy a position different from that of the phosphomonoesterase.
温伯格，拉尔夫（伊利诺伊州皮奥里亚市北部地区研究实验室），以及威廉·L·奥顿。酿酒酵母多聚磷酸盐组分和酸性磷酸单酯酶的合成与分解及其在细胞中的定位。《细菌学杂志》89:740 - 747。1965年。——酿酒酵母细胞中多聚磷酸盐积累的条件在几个方面与酸性磷酸单酯酶的生物合成及维持条件不同。只要有能量来源，静止细胞就能在体内合成或降解多聚磷酸盐。对生长中的细胞进行的实验表明，参与多聚磷酸盐组分代谢的酶系统是组成型的，因为细胞会立即对外界培养基中无机磷酸盐水平的变化做出反应。静止细胞或处于生长延迟期的细胞中酸性磷酸酶水平没有变化。酶的形成或分解仅发生在指数生长期的细胞中。当去阻遏细胞转移到富含磷酸盐的培养基中时，酶会迅速从细胞中丢失，在细胞质量翻倍时降至非常低的值。制备了阻遏细胞的原生质体以确定正磷酸盐和多聚磷酸盐在细胞中的定位。先前的研究表明，当去阻遏细胞变成原生质体时，磷酸单酯酶作为可溶性酶被释放出来。与去阻遏细胞中的磷酸单酯酶不同，阻遏细胞中的两种磷酸盐组分在细胞壁被消化后仍附着在原生质体上，只有当原生质体结构在冷水中裂解时才会被洗脱。然而，如果首先将细胞悬浮在高盐浓度的溶液中，通过渗透休克在没有蜗牛肠提取物的情况下也有可能从完整细胞中提取一部分两种磷酸盐组分。这种盐处理不会影响细胞活力。这些结果除了表明它们与原生质体相关，因此占据与磷酸单酯酶不同的位置外，不允许就正磷酸盐和多聚磷酸盐在细胞中的定位得出明确结论。
