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PubMed · 10030003

Naphthalene uptake by a Pseudomonas fluorescens isolate.

B E Whitman·D R Lueking·J R Mihelcic
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Abstract

The uptake of naphthalene has been investigated in the metabolizing cells of Pseudomonas fluorescens utilizing [1-14C]naphthalene. The uptake displayed an affinity constant (Kt) of 11 microM and a maximal velocity (Vmax) of 17 nmol.h-1.mg-1 cellular dry weight. Naphthalene uptake was not observed in a mutant strain, TG-5, which was unable to utilize naphthalene as a sole source of carbon for growth. Uptake was significantly inhibited (approximately 90%) by the presence of growth-inhibiting levels of either azide or 2,4-dinitrophenol and was sensitive to the presence of structural analogues of naphthalene. The intracellular levels of ATP were not significantly reduced by the presence of either azide or 2,4-dinitrophenol. The presence of alpha-naphthol was found to noncompetitively inhibit naphthalene uptake, displaying a Ki of 0.041 microM. It is concluded that the first step in the utilization of naphthalene by Pseudomonas fluorescens is its transport into the cell by a specific energy-linked transport system.

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2,4-DinitrophenolAdenosine TriphosphateBiodegradation, EnvironmentalBiological Transport, ActiveNaphthalenesNaphtholsPseudomonas fluorescensSodium AzideSoil MicrobiologySoil PollutantsTime FactorsJournal Article

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BibTeXRIS

B E Whitman, D R Lueking, J R Mihelcic. 1998. Naphthalene uptake by a Pseudomonas fluorescens isolate.. https://doi.org/10.1139/cjm-44-11-1086

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