molecular characterization and sequencing of a gene encoding mannose binding protein in an iranian isolate of acanthamoeba castellanii as a major agent of acanthamoeba keratitis

background: acanthamoeba castellanii is the important cause of amoebic keratitis in iran. the key molecule in pathogene­sis of acanthamoeba keratitis is mannose binding protein (mbp) led to adhesion of amoeba to corneal epithelium. subse­quent to adhesion other cytopathic effects occur. the goal of this study was to identify the molecular characterization of a gene encoding mbp in an iranian isolate of a.castellanii in order to pave the way for further investigations such as new therapeu­tic advances or immunization. methods: a.castellanii was cultured on non nutrient agar. extraction of dna was performed by phenol-chloroform method. after designing a pair of primer for the gene encoding mbp, pcr analysis was performed. finally, the pcr prod­uct has been sequenced and the result submitted to the gene data banks. results: an mbp gene of 1081 nucleotides was sequenced. this fragment contained three introns and encodes a protein with 194 amino acids. homology search by blast program showed a significant homology with the mbp gene in gene data banks (96%). besides, the identity of amino acids with the other mbps in gene data banks was about 86%. conclusion: we isolated and sequenced a gene fragment encoding mbp in an iranian isolate of a.castellanii . molecular characteri­zation of this important gene is the first step in pursuing researches such as developing better therapeutic agents, im­mu­nization of population at risk or even developing a diagnostic tool by pcr techniques.