In recent times methanotrophs have gained immense interest due to their ability to sequester and utilize methane, which is an inexpensive carbon source as well as a very potent greenhouse gas. Despite their vast potential for both industrial and environmental applications, only a few methanotrophs have been well studied to date. A novel and an efficient obligate methanotroph was isolated from a methanotrophic consortium originated from a municipal solid waste leachate. The isolate belonged to the genus Methylosarcina as confirmed by 16S ribosomal ribonucleic acid (rRNA) phylogenetic analysis and was further characterized by scanning electron microscopy, chemotaxonomic, and carbon, hydrogen, nitrogen, and sulphur (CHNS) elemental analysis. Methane oxidation by the isolate was studied in detail, including kinetics, specific oxygen requirement, and carbon capture efficiency. Further, the fate of oxidized methane was determined, unraveling its potential in the bioremediation of methane. © 2021 American Society of Civil Engineers.