Isolation and characterisation of a molybdenum-reducing and glyphosate-degrading Klebsiella oxytoca strain SAW-5 in solid from Sarawak

• Main Authors: Sabullah, Mohd Khalizan, Rahman, Mohd Fadhil, Ahmad, Siti Aqlima, Sulaiman, Mohd Rosni, Shukor, Mohd Shukri, Shamaan, Nor Aripin, Abd Shukor, Mohd Yunus
• Format: Article
• Language: English
• Published: Faculty of Agriculture, University of Brawijaya, Indonesia 2016
• Online Access: http://psasir.upm.edu.my/id/eprint/54629/1/Isolation%20and%20characterisation%20of%20a%20molybdenum-reducing%20and%20glyphosate-degrading%20Klebsiella%20oxytoca%20strain%20SAW-5%20in%20solid%20from%20Sarawak%20.pdf; http://psasir.upm.edu.my/id/eprint/54629/; http://www.agrivita.ub.ac.id/index.php/agrivita/article/view/654
• Institution: Universiti Putra Malaysia

Bioremediation of pollutants including heavy metals and xenobiotics is an economic and environmentally friendly process. A novel molyb-denum-reducing bacterium with the ability to utilize the pesticide glyphosate as a carbon source is reported. The characterization works were carried out utilizing bacterial resting cells in a microplate format. The bacterium reduces molybdate to Mo-blue optimally between pH 6.3 and 6.8 and at 34oC. Glucose was the best elec-tron donor for supporting molybdate reduction followed by lactose, maltose, melibiose, raffinose, d-mannitol, d-xylose, l-rhamnose, l-arabinose, dulcitol, myo-inositol and glycerol in descending order. Other requirements include a phosphate concentration at 5.0 mM and a molybdate concentration between 20 and 30 mM. The molybdenum blue exhibited an absorption spec-trum resembling a reduced phospho-molybdate. Molybdenum reduction was inhibited by mercury, silver, cadmium and copper at 2 ppm by 45.5, 26.0, 18.5 and 16.3%, respectively. Biochemical analysis identified the bacterium as Klebsiella oxytoca strain Saw-5. To conclude, the capacity of this bacterium to reduce molybdenum into a less toxic form and to grow on glyphosate is novel and makes the bacterium an important instrument for bioremediation of these pollutants.