The present invention relates to a catalytic material for treating an exhaust gas produced by a natural gas engine, which catalytic material comprises a molecular sieve and a platinum group metal (PGM) supported on the molecular sieve, wherein the molecular sieve has a framework comprising silicon, oxygen and germanium, and has a content of heteroatom T-atoms of ≤about 0.20 mol %, wherein the germanium is present in an amount of from 15 to 20 mol %. The present invention further relates to a catalyst article and a compressed natural gas combustion and exhaust system.