D-Ribulose-5-phosphate is an intermediate in the pentose phosphate pathway. [1][2] It can be derived from 6-phosphogluconate by a dehydrogenase or from xylulose 5-phosphate by ribulose phosphate 3-epimerase. D-Ribulose-5-phosphate is also an intermediate in carbon fixation in photosynthetic organisms as well as in the biosynthesis of lipopolysaccharide, amino acids, secondary metabolites, and antibiotics.[3]
Reference:
[1]. Gumaa, K.A., and McLean, P. The pentose phosphate pathway of glucose metabolism: Enzyme profiles and transient and steady-state content of intermediates of alternative pathways of glucose metabolism in Krebs ascites cells. Biochemistry Journal 115(5), 1009-1029 (1969).
[2]. Patra, K.C., and Hay, N. The pentose phosphate pathway and cancer. Trends Biochem. Sci. 39(8), 347-354 (2014).
[3]. Wolosiuk, R.A., Ballicora, M.A., and Hagelin, K. The reductive pentose phosphate cycle for photosynthetic CO2 assimilation: Enzyme modulation. FASEB J. 7, 622-637 (1993).