...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >ENDOGENOUS K+/H+ EXCHANGE ACTIVITY IN THE SF9 INSECT CELL LINE
【24h】

ENDOGENOUS K+/H+ EXCHANGE ACTIVITY IN THE SF9 INSECT CELL LINE

机译：SF9昆虫细胞系中的内源性K + / H +交换活性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The fluorescent pH indicator 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein (BCECF) was used to investigate changes in the intracellular pH (pH(i)) of individual Sf9 cells in response to changes in the composition of the external medium. Under standard conditions, the resting pH(i) was 0.2-0.3 unit lower than the extracellular pH (6.5). The extracellular concentration of K+ had a major influence on pH(i). Removal of K+ from the medium resulted in a rapid but reversible acidification of the cells. The buffer capacity of the cells was a U-shaped function of pH(i) with a minimum at about pH(i) = 6.2. In the presence of K+, a change in the pH of the medium was followed by an equivalent change in pK(i). In its absence, however, changes in the external pH had little effect on the pH of the cells. Following removal of K+ from the medium, the cells realkalinized at an initial rate which increased with increasing concentration of added K+. This cation was about 30 times more effective in promoting realkalinization of the cells than Li+, Na+, Rb+, and Cs+. The apparent K-m for K+-dependent H+ efflux was about 12 mM and was slightly modulated by extracellular pH. These results strongly suggest that, in Sf9 cells, a K+/H+ antiporter plays a key role in the movement of protons across the cell membrane.
机译：荧光pH指示剂2'，7'-双（羧基乙基）-5,6-羧基荧光素（BCECF）用于研究单个Sf9细胞的细胞内pH（pH（i））响应于其组成变化的变化。外部媒介。在标准条件下，静止pH（i）比细胞外pH（6.5）低0.2-0.3个单位。细胞外K +浓度对pH（i）有重要影响。从培养基中去除K +导致细胞快速但可逆的酸化。细胞的缓冲能力是pH（i）的U形函数，在约pH（i）＝ 6.2时最小。在存在K +的情况下，培养基pH值的变化随后是pK（i）的等效变化。然而，在没有它的情况下，外部pH的变化对细胞的pH几乎没有影响。从培养基中除去K +后，细胞以初始速率重新碱化，并随添加的K +浓度的增加而增加。该阳离子在促进细胞的碱化方面比Li +，Na +，Rb +和Cs +有效约30倍。 K +依赖的H +外流的表观K-m约为12 mM，并受到细胞外pH的轻微调节。这些结果强烈表明，在Sf9细胞中，K + / H +反向转运蛋白在质子穿过细胞膜的移动中起关键作用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号