Plasmid-linked protection of [14C]-glutamate transport and its oxidation against Cd2+ in Staphylococcus aureus.
The effect of Cd2+ on [14C]-glutamate transport energized by endogenous respiration and on glutamate oxidation was studied in the Cd2+-resistant and -sensitive Staphylococcus aureus strains. The results indicate that these processes are protected against 10 microM Cd2+ in the Cd2+ resistant strain 17810R by the 2H+/Cd2+ antiporter encoded by the cadA determinant located on a penicillinase plasmid p II17810. Even at 100 microM Cd2+, glutamate oxidation was only partially inhibited in this organism and this inhibition appeared to be reversible. In the plasmidless variant strain 17810S, which lacks the 2H+/Cd2+ antiporter, both [14C]-glutamate transport and its oxidation was blocked by Cd2+ at 10 or 100 microM. In this strain, Cd2+-mediated inhibition of glutamate oxidation was irreversible. Energetics of glutamate transport in both strains was analyzed.
Tynecka
Z
Z
Department of Pharmaceutical Microbiology, Medical Academy, Lublin, Poland.
Malm
A
A
Skwarek
T
T
Szcześniak
Z
Z
D001692:Biological Transport; D002104:Cadmium / Q000494:pharmacology*; D003470:Culture Media; D004352:Drug Resistance, Microbial; D005947:Glucose / Q000494:pharmacology; D005971:Glutamates / Q000378:metabolism*; D007476:Ionophores / Q000494:pharmacology; D010084:Oxidation-Reduction; D010957:Plasmids; D013211:Staphylococcus aureus / Q000187:drug effects / Q000378:metabolism*
D003470:Culture Media; D005971:Glutamates; D007476:Ionophores; D002104:Cadmium; D005947:Glucose