Bifidobacteria can use the PPP as an alternative glycolytic process to produce lactic and acetic acid from fructose-6-phosphate and indeed PGs involved in the PPP were down-regulated in T1D, such as Phosphogluconate dehydratase (COG0129), Transaldolase (COG0176), Transketolase (COG0021), and Phosphoketolase (COG3957). This evidence concerns the gene TKT and type 1 diabetes mellitus.