Ferredoxin Gene Mutation in Iranian Trichomonas vaginalis Isolates.
BACKGROUND
Trichomonas vaginalis causes trichomoniasis and metronidazole is its chosen drug for treatment. Ferredoxin has role in electron transport and carbohydrate metabolism and the conversion of an inactive form of metronidazole (CO) to its active form (CPR). Ferredoxin gene mutations reduce gene expression and increase its resistance to metronidazole. In this study, the frequency of ferredoxin gene mutations in clinical isolates of T.vaginalis in Tehran has been studied.


METHODS
Forty six clinical T. vaginalis isolates of vaginal secretions and urine sediment were collected from Tehran Province since 2011 till 2012. DNA was extracted and ferredoxin gene was amplified by PCR technique. The ferredoxin gene PCR products were sequenced to determine gene mutations.


RESULTS
In four isolates (8.69%) point mutation at nucleotide position -239 (the translation start codon) of the ferredoxin gene were detected in which adenosine were converted to thymine.


CONCLUSIONS
Mutation at nucleotide -239 ferredoxin gene reduces translational regulatory protein's binding affinity which concludes reduction of ferredoxin expression. For this reduction, decrease in activity and decrease in metronidazole drug delivery into the cells occur. Mutations in these four isolates may lead to resistance of them to metronidazole.
Parasitology and Mycology Dept. Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Soudabeh
S
Heidari
Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran ; Biotechnology Dept. Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mojgan
M
Bandehpour
Parasitology and Mycology Dept. Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Seyyed-Javad
SJ
Seyyed-Tabaei
Parasitology Dept. Pasteur Institute of Iran, Tehran, Iran.
Zarintaj
Z
Valadkhani
Parasitology and Mycology Dept. Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Ali
A
Haghighi
Social Medicine Dept. Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Alireza
A
Abadi
Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran ; Biotechnology Dept. Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Bahram
B
Kazemi
Ferredoxin gene; Mutation; Trichomonas vaginalis