A recombinant microorganism of the genus Escherichia, comprises a genetic modification that increases expression of a nosZ gene encoding NosZ, which is a nitrous oxide reductase, in the recombinant microorganism, wherein the recombinant microorganism comprises a nosR gene encoding NosR, a nosD gene encoding NosD, a nosF gene encoding NosF, a nosY gene encoding NosY, and an apbE gene encoding ApbE, and wherein the nosR gene, the nosD gene, the nosF gene, the nosY gene and the apbE gene are derived from a microorganism of the genus Pseudomonas, the genus Paracoccus, or a combination thereof.

Provided are polynucleotides encoding variants of nitrous oxide reductase proteins, recombinant microorganisms including a foreign gene encoding a variant of a nitrous oxide reductase protein, and a composition comprising the recombinant microorganism or the variant of a nitrous oxide reductase protein for use in removing nitrous oxide in a sample.

A recombinant microorganism of the genus Escherichia, comprises a genetic modification that increases expression of a nosZ gene encoding NosZ, which is a nitrous oxide reductase, in the recombinant microorganism, wherein the recombinant microorganism comprises a nosR gene encoding NosR, a nosD gene encoding NosD, a nosF gene encoding NosF, a nosY gene encoding NosY, and an apbE gene encoding ApbE, and wherein the nosR gene, the nosD gene, the nosF gene, the nosY gene and the apbE gene are derived from a microorganism of the genus Pseudomonas, the genus Paracoccus, or a combination thereof.

A recombinant microorganism having enhanced ability for reducing nitrogen oxide, a composition comprising the recombinant microorganism for use in decreasing a concentration of nitrogen oxide in a sample, and a method of decreasing a concentration of nitrogen oxide in a sample using the recombinant microorganism or the composition.