The relative carbon flux through the alpha- and the beta-keto pathways of leucine metabolism.
Five rat tissues, liver, kidney, heart, brain, and testis, metabolize L-[1-14C]leucine by two pathways. The predominant flux is through the alpha-keto pathway in all tissues; the flux in the beta-keto pathway is approximately 1 to 5% of the total flux for all tissues except the testis where the flux in the beta-keto is one-third of the total flux. Intrinsic factor, which binds the cobalamin cofactor of leucine 2,3-aminomutase, effectively blocked the beta-keto pathway.
D000818:Animals; D001921:Brain / Q000378:metabolism; D002250:Carbon Radioisotopes; D007651:Keto Acids / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D007930:Leucine / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism; D009928:Organ Specificity; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000378:metabolism
D002250:Carbon Radioisotopes; D007651:Keto Acids; C013082:alpha-ketoisocaproic acid; D007930:Leucine