Investigations on nucleotide binding sites of isolated chloroplast ATPase by modification with 7-chloro-4-nitrobenzofurazan
نویسندگان
چکیده
منابع مشابه
7-Chloro-4-nitrobenzofurazan inactivates chloroplast H(2+)-ATPase by modification of different tyrosines, depending on the presence of ATP.
The addition of 7-chloro-4-nitrobenzofurazan (NBD) to isolated CF1 at pH 7.5 leads to one tyrosine-bound NBD molecule per CF1 in one of the three beta-subunits, concomitantly with the inhibition of the ATPase activity. Addition of ADP prior to NBD-incubation protected the ATPase activity and reduced binding of NBD to beta-subunits. The addition of MgATP prior to modification did not result in p...
متن کاملSynthesis of 4-aryloxy-7-nitrobenzofurazan Derivatives from 4-chloro-7-nitrobenzofurazan and Various Phenoxide Anions (Including Pharmaceuticals) in the Presence of Crown Ethers
4-Chloro-7-nitrobenzofurazan reacts by nucleophilic substitution with phenoxide anions derived from estriol (2c), ethynylestradiol (2d), phenol (3e), guaiacol (3f ), 2,6dimethoxyphenol (3g), eugenol (3h), isoeugenol (3i), the cytostatic Etoposide (4), and Reichardt’s betaine (5) in the presence of crown ethers a¬ording the corresponding 4-aryloxy7-nitrobenzofurazan derivatives 6c, 6d, 7e { 7i, ...
متن کاملImpairment of the catalytic activity of Escherichia coli ribonucleic acid polymerase by a unique reaction of 4-chloro-7-nitrobenzofurazan.
Escherichia coli RNA polymerase loses 55-65% of its catalytic activity on reaction with Nbf-Cl (4-choro-7-nitrobenzofurazan). This partial inactivation was shown to be the result of specific impairment of RNA-chain elongation, since initiation of RNA chains was not altered after treatment with Nbf-Cl. The site of reaction was shown to be a unique thiol on the beta-subunit. This thiol is not acc...
متن کاملCharacterization of nucleotide-binding sites on the chloroplast coupling factor 1 using two photolabile analogs.
Nucleotide-binding sites on the chloroplast coupling factor 1 (CF1) have been probed using two photoreactive ADP analogs: 2-azido-ADP (2-N3-ADP) and 2',3'-O-(4-benzoyl)benzoyl-ADP (Bz-ADP). Photolabeling of the isolated CF1 with 2-N3-ADP results in incorporation of the analog exclusively into the beta-subunit of the enzyme. The location of the nucleotide-binding site(s) within the beta-subunit ...
متن کاملNucleotide binding sites on beef heart mitochondrial F1-ATPase. Cooperative interactions between sites and specificity of noncatalytic sites.
We have studied the properties of beef heart mitochondrial F1 having inhibitory MgADP bound at one of the three catalytic sites and various levels of occupancy of the three noncatalytic nucleotide sites including zero, two, or three ADP/ATPs or two ADP/ATP plus one GTP. The properties examined include the rate of MgATP-dependent reactivation and the rate of increase in the fraction of F1 contai...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: FEBS Letters
سال: 1989
ISSN: 0014-5793
DOI: 10.1016/0014-5793(89)81681-3