PCR-RFLP of Coxiella burnetii Plasmids Isolated from Raw Milk Samples in Iran.

Khademi, Payman; Ownagh, Abdulghaffar; Mardani, Karim; Khalili, Mohammad

Background and Aim: Several methods have been employed to identify Coxiella burnetii isolates based on the specific C. burnetii QpH1 plasmid to distinguish the acute form from the chronic form of Q fever disease in humans and animals owing to the presence of unique gene sequences in this plasmid. Therefore, the present study aimed to investigate the panel of nucleic acid fragments resulting from the enzymatic cleavage in the QpH1 plasmid isolated from cow and buffalo milk by nested polymerase chain reaction (Nested-PCR). Materials and Methods: A total of 86 isolates of C. burnetii QpH1 plasmid, which was confirmed by the Nested-PCR method in 2018, were used to determine the RFLP panel of the QpH1 plasmid. Plasmids were first extracted with the kit and were then affected by the Hph1 restriction enzyme. Additionally, 4 nucleic acid samples were sent to Pishgam Company for sequencing with the IS1111 gene primer. Results: Based on the results of the PCR-RFLP test, all plasmid samples showed a similar two-fragment pattern under the influence of Hph1. The results of the nucleic acid sequencing of all 4 samples indicated that they had a C. burnetii type (Nine Mile RSA493 strain). Conclusion: RFLP patterns exhibited no difference on the C. burnetii QpH1 plasmid isolated from cow and buffalo milk. Hence, all isolates were genetically identical, and the infection in animals could originate from one C. burnetii strain (Nine Mile RSA493 strain).

IRAN; NUCLEIC acid analysis; MILK microbiology; Q fever; CATTLE; SEQUENCE analysis; PLASMIDS; GENETIC polymorphisms; RESEARCH funding; DISEASE susceptibility; DESCRIPTIVE statistics; POLYMERASE chain reaction; DATA analysis software

Iranian Journal of Medical Microbiology, 2023, Vol 17, Issue 1, p66

1735-8612

Academic Journal

10.30699/ijmm.17.1.66