TOMM34 is involved in the import of precursor proteins into mitochondria. The protein has a chaperone-like activity, binding the mature portion of unfolded proteins and aiding their import into mitochondria. This protein, which is found in the cytoplasm and sometimes associated with the outer mitochondrial membrane, has a weak ATPase activity and contains 6 TPR repeats. Recombinant human TOMM34 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.