Catalyzes the oxidation of glucose 6-phosphate to 6-phosphogluconolactone. Probable source of extracellular death factor (EDF, sequence Asn-Asn-Trp-Asn-Asn, NNWNN) following processing and amidation. This pentapeptide stimulates cell death mediated by MazF (PubMed:17962566). Artificial peptides with altered sequence show that NNGNN, GNWNG and NWN no longer stimulate MazF's endoribonuclease activity; other peptides (NNGN, GNWMM, NNWNG, NNNWNNN) retain MazF-stimulating activity. NNWNN, NNGN, GNWMM and NNWNG prevent cognate antitoxin MazE from inhibiting MazF; although NNNWNNN stimulates MazF it does not do so in the presence of MazE. EDF also stimulates ChpB's endoribonuclease activity in vitro; in this case NWN partially stimulates ChpB, whereas NNGNN, GNWNN, NNWNG, GNWNG and NNNWNNN do not. Only the wild-type EDF peptide prevents cognate antitoxin ChpS from inhibiting ChpB (PubMed:21419338). D-glucose 6-phosphate + NADP(+) = 6-phospho-D-glucono-1,5-lactone + H(+) + NADPH Carbohydrate degradation; pentose phosphate pathway; D-ribulose 5-phosphate from D-glucose 6-phosphate (oxidative stage): step 1/3. EDF binds to MazF; mutated EDF (sequence NNGNN) does not. Probably processed by the ClpPX protease to generate the extracellular death factor (EDF). It is thought that processing produces Asn-Asn-Trp-Asp-Asn which is amidated to generate Asn-Asn-Trp-Asn-Asn (Probable). Loss of production of extracellular death factor. Belongs to the glucose-6-phosphate dehydrogenase family. Strain K12 / MG1655 is deficient in both production and response to EDF, unlike strains K12 / MC4100, K12 / W3110 and K12 / K38, all of which make and respond to EDF.