Molybdate reduction by Pseudomonas sp. strain DRY2.

Aims:To isolate and characterize a potent molybdenum-reducing bacterium.Methods and Results:A minimal salt medium supplemented with 10 mmol l)1molybdate, glucose (1Æ0%, w⁄v) as a carbon source and ammonium sulfate(0Æ3%, w⁄v) as a nitrogen source was used in the screening process. A molyb-denum-reduc...

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Bibliographic Details
Main Authors: Abd. Shukor, Mohd. Yunus, Ahmad, Siti Aqlima, Mohd Nadzir, Mas Muniroh, Abdullah, M. P., Shamaan, Nor Aripin, Syed, Mohd. Arif
Format: Article
Language:English
English
Published: The Society for Applied Microbiology 2010
Online Access:http://psasir.upm.edu.my/id/eprint/22229/
http://psasir.upm.edu.my/id/eprint/22229/1/Molybdate%20reduction%20by%20Pseudomonas%20sp.pdf
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Summary:Aims:To isolate and characterize a potent molybdenum-reducing bacterium.Methods and Results:A minimal salt medium supplemented with 10 mmol l)1molybdate, glucose (1Æ0%, w⁄v) as a carbon source and ammonium sulfate(0Æ3%, w⁄v) as a nitrogen source was used in the screening process. A molyb-denum-reducing bacterium was isolated and tentatively identified as Pseudomo-nassp. strain DRY2 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. Strain DRY2 produced 2 Æ4,3Æ2 and 6Æ 2 times more molybdenum blue compared to Serratia marcescens strain DRY6,Enterobacter cloacae strain 48 and Eschericia coliK12, respectively.Molybdate reduction as optimum at 5 mmol l)1phosphate. The optimum molybdate concentration that supported molybdate reduction at 5 mmol l)1phosphate was between 15 and 25 mmol l)1. Molybdate reduction was optimum at 40C and at pH 6Æ0. Phosphate concentrations higher than 5 mmol l)1 strongly inhibited molybdate reduction. Inhibitors of electron transport system such as antimycin A, rotenone, sodium azide and cyanide did not inhibit the molybdenum-reducing enzyme activity. Chromium, copper, mercury and lead inhibited the molybdenum-reducing activity.Conclusions:A novel molybdenum-reducing bacterium with high molybdenum reduction capacity has been isolated. Significance and Impact of the Study:Molybdenum is an emerging global pollutant that is very toxic to ruminants. The characteristics of this bacterium suggest that it would be useful in the bioremediation of molybdenum pollutant.