通过血膜的H+和K+循环对于细菌生长不是必需的
概括
如果离子梯度短路,Streptococcus faecalis可以在没有质子循环的情况下生长. 这表明,维持细胞质pH值对于细胞核心功能 (如DNA复制或分裂) 并非必不可少.
科学领域:
- 微生物学 微生物学
- 细胞生理学 细胞生理学
背景情况:
- 球菌的生长受到环境因素的影响.
- 像格拉米西丁这样的离子体会影响膜潜力和离子运输.
研究的目的:
- 研究质子循环和离子梯度在Streptococcus faecalis生长中的作用.
- 为了确定细胞质 pH 维护是否对细胞活力至关重要.
主要方法:
- 在格拉米西丁和其他离子体的存在下培养Streptococcus faecalis.
- 操纵整个等离子膜的pH和电位梯度.
- 在短路离子电流条件下监测增长.
主要成果:
- 当离子梯度 (pH,电位) 被取消时,Streptococcus faecalis表现出正常的生长.
- 增长依赖于丰富的介质,性pH值和高的外部 (K+).
- 对DNA复制,细胞分裂或结构组装来说,质子循环并不必不可少.
结论:
- 质子循环对于Streptococcus faecalis.的基本生物合成过程来说并不必不可少.
- 细菌可以在细胞质pH值没有被质子梯度积极维持的条件下适应和生长.
更多相关视频
05:42Measurement of Ion Concentration in the Unstirred Boundary Layer with Open Patch-Clamp Pipette: Implications in Control of Ion Channels by Fluid Flow
Published on: January 7, 2019
10:08Study of the Functions and Activities of Neuronal K-Cl Co-Transporter KCC2 Using Western Blotting
Published on: December 9, 2022
相关概念视频
Ion Channels
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
The Resting Membrane Potential
Overview
Membrane Proteins
Plasma membranes have integral transmembrane proteins involved in facilitated transport. These proteins are collectively referred to as transport proteins, and they function as either channels for the material or as carriers themselves. Channel proteins have hydrophilic domains exposed to the intracellular and extracellular fluids and a hydrophilic channel through their core that provides a hydrated opening for solutes to pass through the membrane layers. Passage through the channel allows...
Non-gated Ion Channels
Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is to maintain the membrane potential which is critical for cell viability. These channels are either gated or non-gated and can transport more than a thousand ions within milliseconds for the cellular event to occur.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Resting Potential Decay
The resting membrane potential of a neuron (-70mV) is sustained due to the selective ion permeability of the membrane. At the resting potential, the membrane is slightly permeable to ions like sodium (Na+) and chloride (Cl−) and highly permeable to potassium ions (K+). Differences in the ions' concentration inside the cell compared to the outside are maintained by membrane transport proteins like channels and pumps.
At rest, the K+ is the main ion that moves across the membrane through...
At rest, the K+ is the main ion that moves across the membrane through...
Non-gated Ion Channels
Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is to maintain the membrane potential which is critical for cell viability. These channels are either gated or non-gated and can transport more than a thousand ions within milliseconds for the cellular event to occur.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
