title: Metal chelating properties of pyridine-2,6-bis(thiocarboxylic acid) produced by Pseudomonas spp. and the biological activities of the formed complexes.
abstract: We evaluated the ability of pyridine-2,6-bis(thiocarboxylic acid) (pdtc) to form complexes with 19 metals and 3 metalloids. Pdtc formed complexes with 14 of the metals. Two of these metal:pdtc complexes, Co:(pdtc)2 and Cu:pdtc, showed the ability to cycle between redox states, bringing to 4 the number of known redox-active pdtc complexes. A precipitant formed when pdtc was added to solutions of As, Cd, Hg, Mn, Pb, and Se. Additionally, 14 of 16 microbial strains tested were protected from Hg toxicity when pdtc was present. Pdtc also mediated protection from the toxic effects of Cd and Te, but for fewer strains. Pdtc by itself does not facilitate iron uptake, but increases the overall level of iron uptake of Pseudomonas stutzeri strain KC and P. putida DSM301. Both these pseudomonads could reduce amorphous Fe(III) oxyhydroxide in culture. In vitro reactions showed that copper and pdtc were required for this activity. This reaction may derive its reducing power from the hydrolysis of the thiocarboxyl groups of pdtc.
authors.affiliation: Environmental Biotechnology Institute, University of Idaho, Moscow 83844-1052, USA.
authors.forename: Marc S
authors.initials: MS
authors.lastname: Cortese
authors.forename: Andrzej
authors.initials: A
authors.lastname: Paszczynski
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Lewis
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sebat
authors.forename: Vladimir
authors.initials: V
authors.lastname: Borek
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Crawford
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D002176:Candida albicans / Q000187:drug effects / Q000254:growth & development; D002614:Chelating Agents / Q000378:metabolism* / Q000494:pharmacology*; D003952:Diagnostic Imaging; D007501:Iron / Q000378:metabolism; D013058:Mass Spectrometry; D019216:Metals, Heavy / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011549:Pseudomonas / Q000737:chemistry*; D011725:Pyridines / Q000378:metabolism* / Q000494:pharmacology*
chemical_list: D002614:Chelating Agents; D019216:Metals, Heavy; D011725:Pyridines; C120960:pyridine-2,6-bis(thiocarboxylic acid); D007501:Iron