Page 54 - Тахианаас хүнсний хордлого үүсгэгч CAMPYLOBACTER SPP.-ийг илрүүлсэн судалгааны дүн

[ШИНЖЛЭХ УХААНЫ МАГИСТРЫН ЗЭРЭГ ГОРИЛСОН БҮТЭЭЛ] Хураангуй
Дүгнэлт

RESULTS.
We isolated 36 Campylobacter spp. from 96 samples using selective preculture with

Preston-media and mCCDA selective agar plate under microaerobic condition. Multi-plex PCR

that distinguishes Campylobacter species revealed that 29 of 36 isolates were C. jejuni and the
remaining 7 isolates were C. coli. Then, we analyzed antibiotic resistance of the isolates using

E-test. Thirty-five out of 36 isolates were resistant to tetracycline. Two isolates were resistant to

erythromycin that is used for treatment of severe Campylobacter infection in human. Regarding
fluoroquinolone resistance, 20 of 36 isolates (55.6%) were resistant to four fluoroquinolones,

nalidixic acid, ofloxacin, norfloxacin, and ciprofloxacin. To confirm the fluoroquinolone

resistance, we analyzed nucleotide sequences of GyrA gene of the isolates. All the
fluoroquinolone sensitive isolates possessed threonine at codon 86 as expected; however, all

the fluoroquinolone resistant isolates possessed amino aicd substitution from threonine to

isoleucine at codon 86 (nucleotide substitution: ACA to ATA). To characterize the isolate
genetically, Multi Locus Sequence Type (MLST) analysis was carried out. MLST analysis

revealed that many of the isolates belonged to Sequence Type (ST)-828, ST-574, ST-464, ST-

49, ST-22, or ST-21, which are observed worldwide. However, 4 C. jejuni isolates were found to
be similar to recent China isolates. The results will be an important information on

Campylobacter spp. in this country.

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