Nutritional complementation of oxidative glucose metabolism in Escherichia coli via pyrroloquinoline quinone-dependent glucose dehydrogenase and the Entner-Doudoroff pathway.
Two glucose-negative Escherichia coli mutants (ZSC113 and DF214) were unable to grow on glucose as the sole carbon source unless supplemented with pyrroloquinoline quinone (PQQ). PQQ is the cofactor for the periplasmic enzyme glucose dehydrogenase, which converts glucose to gluconate. Aerobically, E. coli ZSC113 grew on glucose plus PQQ with a generation time of 65 min, a generation time about the same as that for wild-type E. coli in a defined glucose-salts medium. Thus, for E. coli ZSC113 the Enter-Doudoroff pathway was fully able to replace the Embden-Meyerhof-Parnas pathway. In the presence of 5% sodium dodecyl sulfate, PQQ no longer acted as a growth factor. Sodium dodecyl sulfate inhibited the formation of gluconate from glucose but not gluconate metabolism. Adaptation to PQQ-dependent growth exhibited long lag periods, except under low-phosphate conditions, in which the PhoE porin would be expressed. We suggest that E. coli has maintained the apoenzyme for glucose dehydrogenase and the Entner-Doudoroff pathway as adaptations to an aerobic, low-phosphate, and low-detergent aquatic environment.
Adamowicz
M
M
School of Biological Sciences, University of Nebraska, Lincoln 68588.
Conway
T
T
Nickerson
K W
KW
D000332:Aerobiosis; D000693:Anaerobiosis; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D003067:Coenzymes / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D042843:Glucose 1-Dehydrogenase; D005948:Glucose Dehydrogenases / Q000378:metabolism*; D006639:Histidine / Q000378:metabolism; D010084:Oxidation-Reduction; D045542:PQQ Cofactor; D018272:Porins; D015363:Quinolones / Q000378:metabolism*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology
D001425:Bacterial Outer Membrane Proteins; D003067:Coenzymes; D018272:Porins; D015363:Quinolones; D012967:Sodium Dodecyl Sulfate; D006639:Histidine; D045542:PQQ Cofactor; D005948:Glucose Dehydrogenases; D042843:Glucose 1-Dehydrogenase; D005947:Glucose