Apoptosis-inducing factor 1, mitochondrial isoform 2 precursor, also known as AIFM1, is a mitochondrial protein that translocates to the nucleus upon induction of apoptosis. AIFM1 has been shown to cause DNA fragmentation and chromatin condensation and to induce the release of cytochrome c and caspase-9 from mitochondria. Bcl-2 overexpression has been shown to prevent the release of AIFM1 from mitochondria, but not to block its apoptogenic activity. Mutations in this gene cause combined oxidative phosphorylation deficiency 6, which results in a severe mitochondrial encephalomyopathy. Recombinant human AIFM1 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.