Application of pulsed-field gel electrophoresis for molecular identification of pathogenic Leptospira species in Iran: a rapid and reliable method

Pejvak Khaki; Mohsen Bagherpour; Mehdi Gharakhani; Maryam Sadat Soltani; Fereshteh Shahcheraghi; Vajihe Sadat Nikbin

doi:10.18502/ijm.v16i3.15763

Pejvak Khaki Department of Microbiology, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
Mohsen Bagherpour Department of Microbiology, Saveh Branch, Islamic Azad University, Saveh, Iran
Mehdi Gharakhani Department of Microbiology, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
Maryam Sadat Soltani Department of Microbiology, Karaj Branch, Islamic Azad University, Karaj, Iran
Fereshteh Shahcheraghi Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
Vajihe Sadat Nikbin Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran

DOI: https://doi.org/10.18502/ijm.v16i3.15763

Keywords: Leptospirosis; Pulsed-field gel electrophoresis; Leptospira serovars; Molecular typing method

Abstract

Background and Objectives: Leptospirosis is a zoonotic disease caused by pathogenic Leptospira serovars. The genus Leptospira cannot differentiated by conventional techniques. However, identity determination of pathogenic serovar is pre- cious of public health problems and epidemiological studies. Pulsed-field gel electrophoresis facilitates rapid identification of Leptospires to the serovar levels.

Materials and Methods: In this study, we employed PFGE to evaluate 28 Leptospira isolates, with animal, human and en- vironmental origin, obtained from Razi Vaccine and Serum Research Institute of Karaj, Iran. PFGE patterns of 28 Leptospira serovars were generated using the Not I restriction enzyme in comparison with the lambda ladder.

Results: Out of 28 serovars evaluated, we identified 22 different pulsed types, designated P1- P22. Out of 22 pulse groups, 3 were found to be a common type, but others were a single Type. Groups consisting of the common type were P3, P9, P14, and P16. The results showed that the discriminatory index of PFGE by Not I enzyme was 0.99, demonstrating heterogeneous differentiation among serovar members.

Conclusion: The PFGE methodology used in this study showed excellent interlaboratory report usability, rapid, reliable, enabling standardization and data sharing between laboratories.