Investigation of Clostin-resistant genes (mcr-pmc) in Klebsiella pneumoniae isolated from raw milk by Multiplex-PCR method

Klebsiella pneumoniae is a gram-negative intestinal bacterium that causes nosocomial infections. The aim of this study was to evaluate the genotype of calcitonin-resistant genes (mcr-pmr) in Klebsiella pneumoniae isolated from raw milk by Multiplex-PCR. Samples were collected from 220 raw milk storage tanks in Tehran milk storage centers in 1977. Klebsiella pneumoniae strains were identified using standard biochemical and microbiological tests. DNA extraction was performed according to the National Center for Genetic and Biological Resources of Iran (MBK0041) kit. After PCR test in thermocycler apparatus to determine the presence of mcr and pmr genes, the samples were transferred onto 1% agarose gel and stained with ethidium bromide and then analyzed in dock gel apparatus. In this study, 60 genotypes of mcr and pmr genotypes were studied in 60 isolates of K. pneumoniae. Meanwhile, the Mcr gene was reported at a frequency of 11, (18.3%) and the Pmr gene was reported at a frequency of 7 (11.6). The trace of the two genes was investigated by Multiplex-PCR method. This seems to be the first study of two Mcr, Pmr genes, in Iran of milk samples isolated from milk storage tanks in industrial farms from Klebsiella pneumoniae and two of these genes were identified as the main marker.