Isolation and Characterization of Partial Sequence of merA Gene from Mercury Resistant Bacterium Klebsiella pneumoniae Isolated from Sario River Estuary Manado

摘要

The most common bacterial mercury resistance mechanism is based on the reduction of Hg2+ to Hg0, which is dependent on the mercuric reductase enzyme (merA) activity. The aims of this research were to isolate and characterize merA gene fragment of mercury resistant bacteria Klebsiella pneumoniae isolate A1.1.1. The gene fragment was amplified by PCR using previously designed primer pairs. Plasmid DNAs were used as template. The result showed that the partial sequence of merA gene has been found on plasmid DNA of mercury resistant bacterium Klebsiella pneumoniae isolates A1.1.1. The nucleotide sequence of the merA gene consists of 285 base pairs (bp) which encodes deduced 94 amino acids of mercury reductase merA protein. The merA protein sequence of isolate A1.1.1 has 99% similarity with some strains of Klebsiella pneumoniae deposited in Gen Bank. There is a gene mutation that causes the deduced amino acid threonine was replaced by serine at position 524 (Thr&rarrSer) in the merA protein of Klebsiella pneumonia as the accession number: AAR91471.1.