원유 시료에서 분리한 장알균속 세균의 다중약물 유출 펌프(Multidrug Efflux Pump) 유전자의 분포도와 항생제 내성 패턴

강소원,이상진,최성숙,Kang, SoWon,Lee, SangJin,Choi, SungSook 한국미생물학회 2013 미생물학회지 Vol.49 No.2

원유시료에서 분리한 장알균속 세균 245균주의 항생제 내성에 관여하는 다중약물 유출 펌프 유전자 분포도와 항생제 내성 패턴을 연구하였다. 그 결과 245 장알균속 균주의 ampicillin에 대한 내성률은 44.1%, erythromycin에 대한 내성률은 79.2%, tetracycline에 대한 내성률은 76.3%, chloramphenicol에 대한 내성률은 36.3%였으며 vancomycin과 ciprofloxacin에 대해서는 모두 감수성임을 알 수 있었다. 내성 관련 유전자 중 MFS타입의 eme(A)는 82.1%의 장알균에 분포하였으며, ABC 타입의 유전자인 efr(A)는 72.7%, efr(B)는 77.1%, lsa는 71.8%의 장알균에 분포하였다. 특히 이러한 유전자의 기원 세균인 Enterococcus faecalis의 경우 eme(A)는 92.5%, efr(A)는 87.4%, efr(B)는 88.4%, lsa는 88.4%의 분포도를 나타내었다. 한편 동일한 장알균속이지만 종이 다른 장알균에서 eme(A)는 E. faecium 4균주, E. avium 7균주, E. durans 4균주 및 E. raffinosus 2균주에 분포하고 있었다. efr(A)는 E. faecium 2균주와 E. durans 2균주에 분포하였으며, efr(B)는 E. faecium 4균주, E. avium 5균주 및 E. durans 4균주에 분포하였다. 본 연구는 우리나라 원유시료에서 분리한 장알균속의 여러 종의 세균에서 동일한 다중약물 유출 펌프(multidrug efflux pump)의 분포에 대한 첫 번째 보고라 사료되며 E. faecalis 이외의 장알균속에서 이러한 유전자의 분포는 서로 다른 종간의 유전자의 수평적인 이동의 가능성을 시사한다. The major aim of this study was to investigate the distribution of genes that encode multidrug efflux pumps in Enterococci spp. isolates from bovine milk samples and antibiotic resistance patterns of these strains. Of the 245 isolates, 44.1% showed ampicillin resistance, 79.2% showed erythromycin resistance, 76.3% showed tetracycline resistance and 36.3% showed chloramphenicol resistance. In case of vancomycin and ciprofloxacin, all of the isolates were susceptible to these antibiotics. Of the 245 enterococcal isolates, 82.1% have MFS type eme(A) gene, 72.7% have ABC type efr(A) gene, 77.1% have ABC type efr(B) gene, and 71.8% have ABC type lsa gene. In case of Enterococcus faecalis, the original strain for these genes, 92.5% have eme(A), 87.4% have efr(A), 88.4% have efr(B), and 88.4% have lsa. Interestingly, in case of different species of Enterococci, eme(A) was also detected in four strains of E. faecium, seven strains of E. avium, four strains of E. durans and two strains of E. raffinosus. efr(A) was also detected in two strains of E. faecium and two strains of E. durans and efr(B) was also detected in four strains of E. faecium, five strains of E. avium and four strains of E. durans. This means the possibility of co-transfer of resistance genes between Enterococci species in natural environment. These results are the first report describing the presence of same multidrug efflux pumps in different species of Enterococci in Korea.

원유시료에서 분리한 대장균의 퀴놀론 항생제 내성 기전

강소원,이상진,최성숙,Kang, Sowon,Lee, Sangjin,Choi, Sungsook 한국미생물학회 2014 미생물학회지 Vol.50 No.3

원유시료에서 분리한 대장균의 quinolone 항생제 내성비율과 그 내성 결정인자를 분석하였다. 원유시료에서 대장균을 분리하고 quinolone 항생제인 nalidixic acid와 ciprofloxacin에 대한 MIC값을 결정하였으며 내성균을 대상으로 염색체상에 있는 quinolone 내성 결정부위(quinolone resistant determining region, QRDR)인 gyrA, gyrB, parC, pareE의 염기서열 분석, 플라스미드상에 존재하는 내성유전자(plasmid mediated quinolone resistant, PMQR) qnrA, qnrB, qnrS, aac(6')-lb-cr, qepA의 분석 및 약물 유출펌프 유전자인 acrB의 발현을 비교 분석하였다. 그 결과 총 487개의 대장균군 세균중 9개의 균이 nalidixic acid에 내성임을 확인하였으며($MIC{\geq}64{\mu}g/ml$) 이중 6개 균주가 ciprofloxacin에도 내성임을 확인하였다(MIC $4-16{\mu}g/ml$)). 9개의 내성 균주 모두 QRDR의 gyrA 영역 codon 83에 변이(S83L)를 갖고 있었으며 그 중 2균주는 codon 83과 87 (S83L and D87N)에 이중 돌연변이를 갖고 있었다. 한편 9균주 중 3개의 균주에서 parC 영역 codon 80 (S80I)에 변이를 갖고 있었다. 플라스미드 상에 존재하는 내성유전자인 qnrA, qnrB, qnrS, aac(6')-lb-cr 및 qepA 유전자는 존재하지 않았으며 AcrAB-TolC efflux pump 유전자인 acrB 유전자가 대조균인 E. coli ATCC 25922와 비교하여 ciprofloxacin 내성 균주 6균주 중 4균주에서 유의적으로 과발현(2.15-5.74배) 되고 있음을 확인하였다. The aim of this study was to investigate the prevalence of quinolone resistant E. coli from raw bulk milk and to characterize the resistance determinants. In this study, the gyrA, gyrB, parC, and parE quinolone resistance determining regions (QRDR) were sequenced from quinolone resistant E. coli isolates. Also, the presence of plasmid-mediated quinolone resistance (PMQR) and the expression of efflux pump genes based on quantitative real-time PCR (qRT-PCR) were investigated. Of the 487 coliform bacteria, 9 strains showed nalidixic acid resistance, and 6 of the 9 nalidixic acid resistant isolates were also ciprofloxacin resistant. These 9 strains had a single mutation at codon 83 (S83L) in gyrA, 2 of them had double mutations at codon 83 and 87 (S83L and D87N) in gyrA and 3 of the 9 isolates had single mutations at codon 80 (S80I) in parC. None of the 9 isolates harbored PMQR determinants. Compared with wild-type E. coli ATCC 25922, an over-expression of the acrB gene (2.15-5.74 fold), encoding the pump component of the AcrAB-TolC efflux pump was observed in 4 of 6 ciprofloxacin resistant isolates. This study identified the quinolone resistance mechanism of E. coli isolated from raw milk samples in Gyeonggi-do.

Study on the Emerging VOCs Analysis Method using Purge&Trap GC/MS in Raw Water and Treated Water

Sowon Kang(강소원),Hyunseung Cho(조현승),Taekkyun Choi(최택균),Sunku Park(박선구),Hakseok Kim(김학석),Sangrak Lee(이상락),Juhyun Park(박주현) 환경독성보건학회 2021 한국독성학회 심포지움 및 학술발표회 Vol.2021 No.5

Volatile Organic Compounds (VOCs) are unsaturated hydrocarbons that cause odors and ozone through volatilization into the atmosphere. In this study, the analysis method of VOCs was performed using Purge & Trap gas chromatography/mass spectrometry. Analysis method was discussed and optimized. The results of 14 VOCs have shown that Method Detection Limit (MDL) was in the range from 0.0098 μg/L to 0.6519 μg/L and Limit of Quantification (LOQ) was in the range from 0.0313 μg/L to 2.0762 μg/L. The results of accuracy and precision ranged from 85.9 % to 114.8 % and 1.0 % to 3.3 %. Investigation of the matrix effects on tap water has shown that this method is suitable for VOCs analysis. Raw water and treated water of 15 water treatment plants were studied by developed method. As a results, Chloromethane was detected in the range from N/D to 1.924 μg/L of raw water and in the range from N/D to 4.595 μg/L of treated water. Detection frequency was 50.0 % of raw water and 86.6 % of treated water. In the case of Chloromethane in raw water, the frequency of detection was decreased during the period of wet season. In addition, in the case of water treatment plant that does not use a coagulant or uses river-side filtered water, the formation of chloromethane was less in treated water. These results are intended to be used as scientific basis data for the preparation of the water quality environment policy system in the future.

Porphyromonas gingivalis의 병인인자 Gingipain 억제능을 갖는 Weisiella cibaria SPM402와 Lactobacillus paracasei SPM412

서채현,강소원,최성숙,Chae Hyeon Seo,Kang SoWon,Sungsook Choi 한국식품위생안전성학회 2023 한국식품위생안전성학회지 Vol.38 No.6

To develop a functional probiotic that inhibits gingipain, a major virulence factor of Porphyromonas gingivlais (P. gingivalis), we screened over 30 probiotic strains for their ability to inhibit gingipian activity. We investigated the inhibition of expression of gingipain genes kgp, rgpA, and rgpB as well as gingipain activity, using freeze dried cell-free supernatants of Weisiella cibaria SPM402 (WC402) and Lactobacillus paracasei SMP412 (LP412), both of which demonstrated antibacterial activity against P. gingivalis. Thus, it was verified that kgp expression was reduced by approximately 0.71±0.02 folds and rgpB expression was reduced by approximately 0.71±0.14 folds at a concentration of WC402 10 mg/mL. Meanwhile, at the same concentration of 10 mg/mL of LP412, kgp expression was reduced by approximately 0.19±0.08 folds, rgpA expression was reduced by approximately 0.09±0.02 folds, and rgpB expression was reduced by approximately 0.24±0.03 folds. At a concentration of 10 mg/mL, Kgp activity was inhibited by approximately 78.65±3.58% (cell associated gingipain, CAG), 82.45±1.22% (cell-free gingipain, CFG) by WC402 and 80.71±2.11% (CAG), and 85.81±0.05% (CFG) by LP412 respectively. Rgp activity was also effectively inhibited by approximately 78.6±1.01% (CAG), 86.78±0.47% (CFG) and 82.93±1.26% (CAG), 88.81±0.36% (CFG) by WC402 and LP412 respectively. Based on these results, W. cibaria SPM402 and L. paracasei SPM412 can be regarded as functional probiotics with the ability to inhibit gingipain activity and exhibit antibacterial effects against P. gingivalis. 치주질환의 원인균인 Porphyromonas gingivlais (P. gingivalis)의 병인인자중 하나인 gingipain 효소에 대한 억제활성을 갖는 유산균을 개발하고자 본 연구실에 보관중인 30여종의 유산균 배양상등액의 활성을 검색하였다. 그 결과 발효식품에서 분리, 동정한 Weisiella cibaria SPM402와 Lactobacillus paracasei SMP412가 P. gingivalis에 대한 항균효과, gingipain 유전자 발현억제 및 gingipain 효소활성 억제능이 확인되었다. W. cibaria SPM402 의 배양 상등액 WC402는 10 mg/mL에서 kgp 유전자는 0.71±0.02배 발현되었고, rgpB 유전자는 0.71±0.14배 발현되 약간의 발현억제 효과가 확인되었다. 반면 L. paracasei SMP412의 배양상등액 LP412는 10 mg/mL 농도에서 kgp 유전자는 0.19±0.08배, rgpA 유전자는 0.09±0.02배, rgpB 유전자는 0.24±0.03배 발현되어 LP412의 뛰어난 gingipain 유전자 발현억제 효과를 확인하였다. 10 mg/mL농도에서, Kgp 효소 활성은 WC 402에 의해 78.65±3.58% (CAG), 82.45±1.22% (CFG), LP412에 의해 80.71±2.11% (CAG), 85.81±0.05% (CFG) 억제되었다. 동일한 농도에서 Rgp 활성은 WC402에 의해 78.6±1.01% (CAG), 86.78±0.47% (CFG), LP412에 의해 82.93 ±1.26% (CAG), 88.81±0.36% (CFG) 억제되었다. 이상의 결과들을 통해 WC402와 LP412는 P. gingivalis에 대한 항균효과 뿐 아니라 병인인자 gingipain을 효과적으로 억제하는 기능성 유산균임을 확인하였다.