D-LACTATE PRODUCTION AND [C-14] SUCCINIC ACID UPTAKE BY ADHERENT AND NONADHERENT ESCHERICHIA-COLI

Escherichia coli isolates of different adherence phenotypes produced d ifferent amounts of D-lactate. Alterations of culture conditions did n ot influence the amount of D-lactate produced. The observed pH decreas es in tissue culture medium corresponded with increases in D-lactate c oncentration. Very little [C-14]succinic acid was incorporated into ce lls during the in vitro incubation of adherent and nonadherent E. coli with HeLa cells, but the amounts of tracer removed from the culture m edium by adherent and nonadherent strains differed. The results are fu rther evidence of a difference in the metabolic behavior of adherent a nd nonadherent E. coli.