Effects of Bacterial Vitamin B6 Metabolism on 5-FU Efficacy, Related to Figure 3
(A) Vitamin B6 pools are altered in ΔpdxH mutant E. coli measured by LC-MS/MS. PLP = Pyridoxal-5-Phosphate; PNP = Pyridoxine-5-Phosphate; PMP = Pyridoxamine-5-Phosphate; PL = Pyridoxal; PN = Pyridoxine; PM = Pyridoxamine; PA = Pyridoxic acid.
(B) Media supplementation with 10 μM PL rescues 5-FU efficacy on worms fed ΔpdxJ bacteria to control levels (BW + PL = 0.25 μM versus BW = 0.25 μM, p = 0.779; ΔpdxJ + PL = 0.25 μM versus ΔpdxJ = 2 μM, p < 0.001; ΔpdxJ + PL = 0.25 μM versus BW = 0.25 μM, p = 1; ΔpdxJ + PL = 0.1 μM versus BW + PL = 0.1 μM, p = 1).
(C) Inhibition of both B6 de novo and salvage pathways using a ΔpdxJΔpdxK double mutant decreases 5-FU efficacy which cannot be rescued by supplementation with 1 mM PN, PM or PL.
(D) Efficient RNAi knockdown of the worm F57C9.1 gene, an ortholog of human PDXK.
(E) Knockdown of F57C9.1 by RNAi does not alter worm responses to 5-FU upon supplementation with PL.
(F) Gene expression levels by qRT-PCR of enzymes involved in the glycine cleavage system, folate and vitamin B6 metabolism in worms grown on ΔpdxJ bacteria.
Data are represented as mean ± SD. ∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001. For statistics, see Table S3.