Rapid photolytic release of adenosine 5'-triphosphate from a protected analogue: utilization by the Na:K pump of human red blood cell ghosts

Journal Article · Tue May 16 04:00:00 EDT 1978 · Biochemistry; (United States)

OSTI ID:6817643

Kaplan, J H; Forbush, B III; Hoffman, J F

2-Nitrobenzyl phosphate and 1-(2-nitro)phenylethyl phosphate have been synthesized and demonstrated to be suitable as photolabile sources of inorganic phosphate. The same protecting groups were attached to the terminal phosphate of adenosine 5'-triphosphate. These caged ATP compounds released adenosine 5'-triphosphate on illumination at 340 nm in aqueous solution and P/sup 3/-1-(2-nitro)phenylethyl-ATP gave about a 70 percent yield in under 30 s. The unphotolyzed caged ATP was neither a substrate nor inhibitor of purified renal Na,K-ATPase (EC 3.61.3). Following photolysis in the presence of the enzyme, the liberated ATP was hydrolyzed but at an inhibited rate. The photo-dependent inhibition could be eliminated by prior addition of glutathione or bisulfite to the irradiated solution. Caged ATP was incorporated into resealed human erythrocyte ghosts prepared from red blood cells depleted of internal energy stores. While the NA : K pump was unable to use incorporated caged ATP as a substrate, the ATP liberated by photolysis activated the pump as evidenced by measurements of K-dependent, ouabain-sensitive Na efflux. Thus the caged ATP can be used as a stable source of ATP unmetabolizable by intracellular ATPases until the ATP is released following photolytic irradiation.

• Research Organization: Yale Univ., New Haven
• OSTI ID: 6817643
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 17:10; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500 -- Photochemistry
550200 -- Biochemistry
560111* -- Radiation Effects on Biochemicals-- In Vitro-- (-1987)
560151 -- Radiation Effects on Animals-- Man
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL COMPOUNDS
ATP
ATP-ASE
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CATALYSIS
CATIONS
CHARGED PARTICLES
CHEMICAL REACTIONS
DECOMPOSITION
ELECTROMAGNETIC RADIATION
ENZYMES
ERYTHROCYTES
ESTERASES
HYDROLASES
IONS
IRRADIATION
KINETICS
MEMBRANE TRANSPORT
NUCLEOTIDES
ORGANIC COMPOUNDS
PHOSPHATASES
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
POTASSIUM COMPOUNDS
RADIATIONS
REACTION KINETICS
SODIUM COMPOUNDS
ULTRAVIOLET RADIATION