Pentose phosphate pathway: phases, reactions, & metabolic roles Glucose metabolism begins with its transport into cells via GLUT transporters, where it is phosphorylated to glucose 6 phosphate (Glucose 6 P). This molecule can enter various pathways, including the pentose phosphate pathway or hexosamine biosynthesis. Pentose Phosphate Pathway (PPP), Purine and Pyrimidine Metabolism Cell Biology, Genetics, and Biochemistry for Pre Clinical Students The Pentose Phosphate Pathway (HMP shunt) & G6PD deficiency (Favism)