Landfills are significant sources of methane, the second most potent greenhouse gas (GHG) after carbon dioxide. Bio-augmented cover systems using methanotrophs are emerging as viable alternatives to conventional gas collection system, due to lower cost and maintenance requirements. Methanotrophs have immense potential for both industrial and environmental applications, because of their ability to utilize and convert methane, which is also an inexpensive carbon source. In this study, an efficient obligate-methanotroph was isolated from a methanotrophic consortium developed from municipal solid waste leachate. The isolate belonged to genus Methylosarcina as confirmed by 16s rRNA phylogenetic analysis and was further characterized by scanning electron microscopy, chemotaxonomic, and CHNS elemental analysis. The oxidation of methane at various initial methane concentrations was studied, and its biokinetic parameters were evaluated. Further effect of several trace metal ions, that play crucial role in methane metabosim were investigated. The strain displayed the high observed specific methane oxidation rate of 11.13 µmol. mgbiomass-1.h-1 and required lower oxygen per methane oxidized compared to other known methanotrophs and methanotrophic consortia with good carbon conversion efficiency of 74%. The isolate shows lot of promise for usage in bio-augmented cover systems for mitigation of methane.