Sodium transport and phosphorus metabolism in sodium-loaded yeast: simultaneous observation with sodium-23 and phosphorus-31 NMR spectroscopy in vivo.
Sodium transport and phosphorus metabolism in sodium-loaded yeast: simultaneous observation with sodium-23 and phosphorus-31 NMR spectroscopy in vivo.
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钠负载酵母中的钠转运和磷代谢：体内钠 23 和磷 31 NMR 光谱同步观察。
DOI：
10.1021/bi00390a011
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发表时间：
1987
期刊：
影响因子：
2.9
通讯作者：
Balschi,JA
中科院分区：
文献类型：
--
作者：
Höfeler,H;Jensen,D;Pike,MM;Delayre,JL;Cirillo,VP;SpringerJr,CS;Fossel,ET;Balschi,JA
1987年3月27日收到的修订版Mandarin pt摘要：从许多酵母悬浮液中同时获得23 Na和31 P NMR光谱。在NMR光谱之前，酵母细胞是Na-负载的：这用Na+取代了一些细胞内的K+。这些细胞也有些缺磷，因为它们在31 P NMR谱中没有可见的多磷酸盐物质。在NMR实验中，将Na负载的细胞悬浮在含有无机磷酸盐、非常低的Na+和用于Na+ NMR信号的位移试剂的介质中。培养基的不同之处在于氧气、葡萄糖或K+是否单独存在或组合存在，以及培养基是否缓冲。核磁共振谱显示细胞总是失去Na+而获得磷。然而，Na+流出时间过程和P代谢的性质取决于培养基。Na+流出通常呈线性进行，直到流出的Na+量大致等于培养基中最初存在的NH 4+和正磷酸盐的量（外部磷酸盐以NH 4 H 2 P 0 4形式加入）。因此，我们假设第一阶段反映了Na+与NH 4+的交换。Na+外流然后进入一个过渡阶段，要么减缓，停止，或短暂逆转，恢复在大约相同的值作为第一阶段。我们推测，这最后一个阶段涉及的同时挤出细胞内阴离子的文献报道。磷代谢变化较大。在没有外源性葡萄糖的情况下，所吸收的P首先以细胞内无机磷酸盐的形式积累;否则，它首先在“糖磷酸盐”池中积累。在大多数情况下，至少有一部分P离开糖磷酸池，进入液泡中的多磷酸盐库。然而，这从未发生，直到可能代表Na+交换NH 4+的阶段完成，并且多磷酸盐池中的P从未永久保留在那里，但最终总是恢复到糖磷酸盐池。这些变化被解释为在不同条件下对细胞的层次energydemands。特别地，用于Na+交换NH 4+的能量优先于产生和储存多磷酸盐所需的能量。这一结论得到了以下事实的支持：当细胞被“强迫”用K+和NH 4+交换Na+时（通过向含NH 4+的培养基中加入5倍的K+），多磷酸盐从未显著形成，并且初始线性Na+流出期可能持续6倍长。多磷酸盐的最终消耗可能是因为代谢过程需要（无机）磷酸盐，而代谢过程产生Na+阴离子共挤出相的阴离子。（1982）和其中引用的参考文献以及Nicolay et al.（1983）和其中引用的参考文献]。在最近的发展中，引入用于阳离子NMR的水性位移试剂（Pike & Springer，1982; Gupta & Gupta，1982）使得区分细胞外和细胞内23 Na和7 Li共振成为可能
Revised Manuscript Received March 27, 1987 abstract: Simultaneous 23Na and 31P NMR spectra were obtained from a number of yeast suspensions. Prior to NMR spectroscopy, the yeast cells were Na-loaded: this replaced some of the intracellular K+ with Na+. These cells were also somewhat P-deficient in that theyjjad no polyphosphate species visible in the 31P NMR spectrum. In the NMR experiments, the Na-loaded cells were suspended in media which contained inorganic phosphate, very low Na+, and a shift reagent for the Na+ NMR signal. The media differed as to whether dioxygen, glucose, or K+ was present individually or in combinations and as to whether the medium was buffered or not. The NMR spectra revealed that the cells always lost Na+ and gained phosphorus. However, the nature of the Na+ efflux time course and the P metabolismdiffered depending on the medium. The Na+ efflux usually proceeded linearlyuntil the amount of Na+ extruded roughly equalled the amount of NH4+ and orthophosphate initially present in the medium (external phosphate was added as NH4H2P04). Thus, we presume this first phase reflects a Na+ for NH4+ exchange. The Na+ efflux then entered a transition phase, either slowing, ceasing, or transiently reversing, before resumingat about the same value as that of the first phase. We presume that this last phase involves the simultaneous extrusion of intracellular anions as reported in the literature. The phosphorus metabolism was much more varied. In the absence of exogenous glucose, the P taken up accumulated first as intracellular inorganic phosphate; otherwise, it accumulated first in the “sugar phosphate” pool. In most cases, at least some of the P left the sugar phosphate pool and entered the polyphosphate reservoir in the vacuole. However, this never happened until the phase probably representing Na+ for NH4+ exchange was completed, and the P in the polyphosphate pool never remained there permanently but always eventually reverted back to the sugar phosphate pool. These changes are interpreted in terms of hierarchical energydemands on the cells under the different conditions. In particular, the energy for the Na+ for NH4+ exchange takes precedence over that required to produce and store polyphosphate. This conclusion is supported by the fact that when the cells are “forced” to exchange K+, as well as NH4+, for Na+(by the addition of 5 times as much K+ to the NH4+-containing medium), polyphosphates are never significantly formed, and the initial linear Na+ efflux phase persists possibly 6 times as long. The ultimate consumption of polyphosphate species probably occurs because (inorganic) phosphate is required for the metabolic processes which produce theanions for the Na+ anion coextrusion phase.I^ iosphorus-31 NMR spectroscopy has been widely used to study yeast metabolism [see Alger et al.(1982) and references cited therein and Nicolay et al.(1983) and references cited therein]. In a more recent development, the introduction of aqueous shift reagents for cation NMR (Pike & Springer, 1982; Gupta & Gupta, 1982) has made possible the discrimination of the extra-and intracellular 23Na and 7Li resonances
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酿酒酵母野生型和糖酵解途径突变体的 Phosphorus-31 核磁共振研究。
影响因子：
2.9
作者：
G. Navon;R. Shulman;T. Yamane;T. Eccleshall;K. Lam;J. J. Baronofsky;J. Marmur
通讯作者：
J. Marmur
酵母中钠流出的机制
影响因子：
3.5
作者：
A. Rodríguez;M. Ortega
通讯作者：
M. Ortega
Phosphor-31 核磁共振研究氧对酵母糖酵解的影响。
影响因子：
2.9
作者：
J. A. D. Hollander;Kamil Ugurbil;T. Brown;Robert G. Shulman
通讯作者：
Robert G. Shulman
用于高分辨率阳离子核磁共振的水相位移试剂。
DOI：
--
发表时间：
1984
期刊：
影响因子：
--
作者：
S. C. Chu;M. Pike;E. Fossel;T. W. Smith;J. Balschi;C. S. Springer
通讯作者：
C. S. Springer
自旋回波核磁共振在全细胞系统中的应用。
影响因子：
4.1
作者：
K. Brindle;F. F. Brown;I. Campbell;C. Grathwohl;P. Kuchel
通讯作者：
P. Kuchel