Diphospho-myo-inositol phosphates from Dictyostelium identified as D-6-diphospho-myo-inositol pentakisphosphate and D-5,6-bisdiphospho-myo-inositol tetrakisphosphate.
Two diphospho-myo-inositol phosphates from Dictyostelium were recently investigated by two-dimensional 1H/31P NMR analysis and assigned to be either D-4-diphospho-myo-inositol pentakisphosphate (D-4-PP-InsP5) and D-4,5-bisdiphospho-myo-inositol tetrakisphosphate (D-4,5-bis-PP-InsP4) or their corresponding enantiomers D-6-PP-InsP5 and D-5,6-bis-PP-InsP4. In the present study the naturally occurring enantiomers were identified by using defined synthetic PP-InsP5 isomers as substrates for a partially purified PP-InsP5 5-kinase from Dictyostelium. This enzyme specifically phosphorylates the naturally occurring PP-InsP5 and the synthetic D-6-PP-InsP5, leading to D-5,6-bis-PP-InsP4. In contrast, neither D-4-PP-InsP5 nor D-1-PP-InsP5 or D-3-PP-InsP5 are converted by the enzyme.
Laussmann
T
T
Fachbereich 9 - Chemie, Bergische Universität GHS Wuppertal, Federal Republic of Germany.
Reddy
K M
KM
Reddy
K K
KK
Falck
J R
JR
Vogel
G
G
D000818:Animals; D004023:Dictyostelium / Q000737:chemistry* / Q000201:enzymology; D007295:Inositol Phosphates / Q000737:chemistry* / Q000378:metabolism; D010766:Phosphorylation; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
D007295:Inositol Phosphates; C081651:inositol-1,4,5,6-tetrakisphosphate; C079849:1-diphosphoinositol pentakisphosphate; D017853:Phosphotransferases (Alcohol Group Acceptor); C064990:inositol pentakisphosphate kinase