Cloning and expression of an integral membrane protein gene of Actinobacillus pleuropneumoniae

To study the immune protective mechanism of Actinobacillus pleuropneumoniae(APP),an integral membrane protein(IM)was identified by screening a phage library of 3~8 kb random DNA fragments of APP.The inserted segment encoding the entire amino acid sequence of the IM was determined by sequencing the rescued plasmids and Blast analysis.Specific primers were designed to amplify the IM gene.The IM was cloned,expressed and purified.Western-blot result showed strong reactivity of the protein with convalescent sera(IgG).These suggest IM plays a role in immune response.