Evidence that a major portion of cellular potassium is bound
- Univ. of Texas Health Science Center, San Antonio (USA)
In this report we briefly review recent evidence which shows that a substantial proportion of intracellular K+ is bound or perturbed from the physicochemical properties expected in dilute aqueous solutions. In addition, we present evidence from electron probe x-ray microanalysis of thin cryosections of cells which indicates that the binding of K+ to anionic groups either carboxyl groups (HCO{sub 2}) on proteins or to phosphate groups in creatine phosphate (CrP), in adenosine triphosphate, (ATP), in protein and in nucleic acids, are the main determinants of the maintenance of (as differentiated from the generated of) the well known intra- to extracellular K+ concentration difference. The collective evidence suggests that much of cellular K+ is reduced in its mobility and in its chemical activity due to association with negative charge groups (e.g. carboxyl and phosphates). This fact forces abandonment of the misleading assumption that the majority of intracellular K+ and other inorganic ions are as free as would be expected under ideal solution conditions. This realization should have far reaching consequences toward understanding transmembrane movement of water and solutes in cells. 41 references.
- OSTI ID:
- 6651039
- Journal Information:
- Scanning Microscopy; (USA), Vol. 4:1; ISSN 0891-7035
- Country of Publication:
- United States
- Language:
- English
Similar Records
Rapid photolytic release of adenosine 5'-triphosphate from a protected analogue: utilization by the Na:K pump of human red blood cell ghosts
The High-Affinity E. Coli Methionine ABC Transporter: Structure And Allosteric Regulation
Related Subjects
ANIMAL CELLS
ELECTRON MICROPROBE ANALYSIS
MEMBRANE TRANSPORT
BIOCHEMISTRY
POTASSIUM COMPOUNDS
CHEMICAL BONDS
AQUEOUS SOLUTIONS
ATP
CELL MEMBRANES
CELL NUCLEI
CHEMICAL PROPERTIES
CREATINE
CYTOPLASM
MAN
NUCLEIC ACIDS
PHOSPHATES
PHYSICAL PROPERTIES
PROTEINS
REVIEWS
ALKALI METAL COMPOUNDS
AMINO ACIDS
ANIMALS
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CHEMICAL ANALYSIS
CHEMISTRY
DISPERSIONS
DOCUMENT TYPES
MAMMALS
MEMBRANES
MICROANALYSIS
MIXTURES
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
PRIMATES
SOLUTIONS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques