A strain of E. coli lacking PdxB (erythronate 4-phosphate dehydrogenase) cannot grow on M9/glucose because it cannot make pyridoxal 5'-phosphate (PLP). We have identified seven enzymes that, when over-expressed, allow this strain to grow on glucose. Five of these have known or putative kinase, phosphatase, or hydrolase activities, but no detectable erythronate 4-phosphate dehydrogenase activity. Genetic analyses suggest that these enzymes facilitate two latent pathways that allow E. coli to produce a metabolite downstream of the block in the ΔpdxB::kan strain. We have identified enzymes responsible for three of four steps required for one of these pathways. This pathway is clearly not a bona fide pathway that has evolved as an alternative way to synthesize PLP. Reactions in the pathway are catalyzed with very poor catalytic efficiencies by either broad specificity enzymes or promiscuous activities of enzymes that serve other functions. This work demonstrates the potential for patching together novel metabolic pathways provided by the complement of promiscuous activities residing within a modest bacterial proteome.