Mitochondrial metabolism of guanine nucleotides. Possible role of guanosine.
The catabolism of intramitochondrial guanine nucleotides was examined. During 30 min incubation of rat liver mitochondria at 37 degrees C in the presence of oligomycin and carboxyatractyloside, guanine and xanthine were formed and appeared in the medium. Under these conditions, the direct conversion of GMP to guanine by hypoxanthine-guanine phosphoribosyltransferase is suggested to be the main catabolic route within the organelles. Only very small amounts of guanosine were produced and detected both inside and outside the organelles. [14C]Guanosine and [14C]inosine were taken up by the mitochondria. Therefore, guanosine is suggested to be a precursor of intramitochondrial guanine nucleotides.
Ziegler
M
M
Department of Biochemistry, School of Medicine, Humboldt University, Berlin, GDR.
Dubiel
W
W
Pimenov
A M
AM
Tikhonov
Y V
YV
Toguzov
R T
RT
Henke
W
W
Gerber
G
G
D000818:Animals; D001278:Atractyloside / Q000031:analogs & derivatives / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D006147:Guanine / Q000096:biosynthesis; D006150:Guanine Nucleotides / Q000378:metabolism*; D006151:Guanosine / Q000378:metabolism*; D007288:Inosine / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism*; D009840:Oligomycins / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013347:Subcellular Fractions / Q000378:metabolism; D013696:Temperature; D019820:Xanthine; D014970:Xanthines / Q000096:biosynthesis
D006150:Guanine Nucleotides; D009840:Oligomycins; D014970:Xanthines; D006151:Guanosine; D001278:Atractyloside; D019820:Xanthine; D007288:Inosine; D006147:Guanine; C003853:carboxyatractyloside