Premium
Reduction of molybdate to molybdenum blue by Klebsiella sp. strain hkeem
Author(s) -
Lim H. K.,
Syed M. A.,
Shukor M. Y.
Publication year - 2012
Publication title -
journal of basic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.58
H-Index - 54
eISSN - 1521-4028
pISSN - 0233-111X
DOI - 10.1002/jobm.201100121
Subject(s) - molybdate , molybdenum , sodium molybdate , chemistry , molybdenum blue , nuclear chemistry , strain (injury) , inorganic chemistry , oxalate , cyanide , biochemistry , phosphate , biology , anatomy
A novel molybdate‐reducing bacterium, tentatively identified as Klebsiella sp. strain hkeem and based on partial 16s rDNA gene sequencing and phylogenetic analysis, has been isolated. Strain hkeem produced 3 times more molybdenum blue than Serratia sp. strain Dr.Y8; the most potent Mo‐reducing bacterium isolated to date. Molybdate was optimally reduced to molybdenum blue using 4.5 mM phosphate, 80 mM molybdate and using 1% (w/v) fructose as a carbon source. Molybdate reduction was optimum at 30 °C and at pH 7.3. The molybdenum blue produced from cellular reduction exhibited absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Inhibitors of electron transport system such as antimycin A, rotenone, sodium azide, and potassium cyanide did not inhibit the molybdenum‐reducing enzyme. Mercury, silver, and copper at 1 ppm inhibited molybdenum blue formation in whole cells of strain hkeem. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)