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The transport of citrate and other tricarboxylic acids in two species of Pseudomonas.

ABSTRACT: When cells of Pseudomonas are grown on citrate as the sole carbon source they oxidize citrate and isocitrate rapidly. Fluorocitrate inhibits the oxidation of citrate. Fluorocitrate-treated cells accumulate [6-(14)C]citrate, as shown by a rapid Millipore-filtration technique. In the absence of fluorocitrate most of the [6-(14)C]-citrate is lost in the form of (14)CO(2). The isolation of a pseudomonad characterized by its ability to grow on tricarballylate as a sole carbon source has facilitated the study of the tricarboxylate-carrier specificity. Cells grown on citrate will exchange radioactive citrate for unlabelled citrate or isocitrate but not for cis-aconitate, trans-aconitate or tricarballylate. Cells grown on tricarballylate will exchange radioactive citrate for unlabelled citrate, cis-aconitate or tricarballylate, but not for isocitrate or trans-aconitate. The properties of the exchange system involved are compared with those of the related system in mitochondria.

SUBMITTER: Lawford HG

PROVIDER: S-EPMC1176996 | biostudies-other | 1971 Jul

REPOSITORIES: biostudies-other

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