With the increasing incorrect use or even abuse of antibiotics,the rapid emergence of various G+ resistant bacteria,such as MRSA.MRSE,VRE.presents a very serious threat to public health.Therefore.searching for new targets and developing new drugs with novel mechanisms and potent activity against G-resistant bacteria has become an urgent need and an international research project.Peptide deformylase (PDF) is an essential enzyme in the protein maturation of prokaryote and regarded as one ideal target for the design of new broad-spectrum antibiotics.In this study,pdf of E.faecium was cloned and expressed.The protein PDF obtained was purified by Ni2+ metal chelating affinity chromatography column and was identified by Western blotting and activity assaying.