Activity of one of the nucleotide-binding domains of CFTR in vitro

Range ~0.008 1/sec
Organism Eukaryotes
Reference Nikaido K, Liu PQ, Ames GF. Purification and characterization of HisP, the ATP-binding subunit of a traffic ATPase (ABC transporter), the histidine permease of Salmonella typhimurium. Solubility, dimerization, and ATPase activity. J Biol Chem. 1997 Oct 31 272(44):27745-52. p.27752 left column 4th paragraphPubMed ID9346917
Primary Source Ko YH, Pedersen PL The first nucleotide binding fold of the cystic fibrosis transmembrane conductance regulator can function as an active ATPase. J Biol Chem. 1995 Sep 22 270(38):22093-6.PubMed ID7545672
Comments "Among eukaryotic traffic ATPases, a comparison can be made with one of the nucleotide-binding domains of CFTR (the amino-terminal one) which has been characterized in vitro as a soluble protein fused to the maltose-binding protein (primary source). Its affinity for ATP is 110µM and comparable to that of the prokaryotic systems its activity, 0.008 s^-1, is much lower than that of the prokaryotic subunits, possibly due to the fact that since the membrane-spanning and nucleotide-binding domains of CFTR normally form a single protein, their ability to impart positive regulatory stimuli may have been eliminated in the chimeric product." CFTR=cystic fibrosis transmembrane conductance regulator
Entered by Uri M
ID 109036