Biosynthesis and metabolism of 9-[5'-deoxy-5'-(methylthio)-beta-D-xylofuranosyl]adenine, a novel natural analogue of methylthioadenosine.
The biosynthesis of 9-[5'-deoxy-5'-(methylthio)-beta-D-xylofuranosyl]adenine (xylosyl-MTA), a naturally occurring analogue of 5'-deoxy-5'-methylthioadenosine (MTA) recently characterized, was studied in the nudibranch mollusc Doris verrucosa. Experiments performed in vivo with putative labelled precursors such as [8-14C]adenine, [Me-14C]methionine and [Me-14C]MTA indicate that xylosyl-MTA originates from MTA. Experiments with MTA double-labelled at critical positions are consistent with a 3'-isomerization of the nucleoside through the formation of a 3'-oxo intermediate. In addition, experiments with the newly synthesized [3'-3H]xylosyl-MTA are indicative for a very low turnover rate of this molecule, which therefore accumulates in the mollusc.
Porcelli
M
M
Istituto di Biochimica delle Macromolecole, I Facoltà di Medicina e Chirurgia, Università di Napoli, Italy.
Cacciapuoti
G
G
Cimino
G
G
Gavagnin
M
M
Sodano
G
G
Zappia
V
V
D000241:Adenosine / Q000031:analogs & derivatives* / Q000378:metabolism; D000818:Animals; D003839:Deoxyadenosines / Q000096:biosynthesis* / Q000378:metabolism; D008974:Mollusca / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism; D011683:Purine-Nucleoside Phosphorylase / Q000378:metabolism; D013872:Thionucleosides / Q000378:metabolism*
D003839:Deoxyadenosines; D011073:Polyamines; D013872:Thionucleosides; C056833:9-(5'-deoxy-5'-(methylthio)-xylofuranosyl)adenine; C008500:5'-methylthioadenosine; D011683:Purine-Nucleoside Phosphorylase; C021784:5'-methylthioadenosine phosphorylase; D000241:Adenosine