• 한국잡초학회지
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• 제15권1호
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• pp.63-72
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• 1995

제초제(除草劑) Napropamide의 분해능(分解能)이 뛰어난 균주(菌株)를 선발(選拔)하고 그의 분해특성(分解特性)을 구명(究明)할 목적(目的)으로 농약(農藥) 무처리토양(無處理土壤)으로부터 세균(細菌)을 분리(分離)한 후(後) 이들 균(菌)을 Napropamide 함유(含有) NB배지(培地)에 접종(接種)하여 생존력(生存力)과 Napropamide 분해능(分解能)을 조사(調査)하였으며, 분해능(分解能)이 우수(優秀)한 세균(細菌)에 대해 Napropamide를 탄소원(炭素源) 혹은 질소원(窒素源)으로서의 이용여부(利用與否)와 반복처리(反覆處理)에 의한 세균(細菌)의 Napropamide 분해양상(分解樣相)을 조사(調査)하였는 바 그 결과는 다음과 같다. 공시토양(供試土壤)인 식양토(埴壤土)에서 분리(分離)한 세균(細菌)은 그람양성균(陽性菌) 및 그람음성균(陰性園)이 각각(各各) 4속(屬) 10균주(菌株)씩이었고, 이들 세균(細菌)의 Napropamide에 대한 생존력시험(生存力試驗)에서 공시균주(供試菌株) 모두 100ppm에서는 활발(活撥)하게 증식(增植)되었고 1500ppm까지 생존력(生存力)이 뛰어난 균주(菌株)는 Staphylococcus속(屬) 2균주(菌株), Corynebacterium속(屬) III, 기타(其他) 속(屬) II이었다. 공시균주중(供試菌株中) 20%이상(以上) Napropamide 분해능(分解能)을 가진 세균(細菌)은 Staphylococcus속(屬) II와 Actinobacillus속(屬) I이었고, 이들 두 균주(菌株)는 Napropamide를 단일(單一) 질소원(窒素源)으로서는 이용(利用)하지 못하였으나, Staphylococcus속(屬) II가 Napropamide를 단일(單一) 탄소원(炭素源)으로 이용(利用)하는 것으로 나타났다. Napropamide의 반응처리(反覆處理)에 따른 Staphylococcus속(屬) II의 공시약제(供試藥劑)의 분해(分解)는 1회처리(回處理)에서 급속(急速)히 분해(分解)되었고 2회연용처리(回連用處理) 후(後)에는 분해(分解)가 지연(遲延)되었으나 3회연용처리(回連用處理)에서는 다시 급속(急速)한 분해(分解)가 일어났다.

• 미생물학회지
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• 제33권3호
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• pp.175-180
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• 1997

인위적으로 pH 구배가 조성딘 회분배양 시스템(batch culture system)내에서 종속영양 세균 군집의 종조성 변화에 미치는 산성화의 영향을 수리학적으로 분석하였다. 총세균의 개체수는 산성화에 영향을 받지 않았으며, 종속영양 세균 군집의 크기는 pH가 낮아질수록 감소하였다. 전 pH 구간에서 분리된 종속영양 세균들은 모두 12속 22종으로 나타났으며, 이중 그람음성 세균은 64%, 그람양성 세균은 36%의 비율로 분포하였다. pH가 낮아짐에 따라 그람양성 세균의 분포 비율은 감소하는 반면, 그람음성 세균의 분포 비율은 증가하는 양상을 보였다. 각 pH 구간별 속의 분포 비율은 pH 7에서는 12개 속이 출현하였으나, pH 3에서는 5개 속만 출현하여 pH가 낮아짐에 따라 속의 다양성이 감소하는 양상을 나타내었다. 종 다양성 지수는 1.13-2.37이 범주였으며, pH가 낮아질수록 종 다양성 지수가 낮게 나타났다. 크기가 다른 군집의 다양성 평가를 위해 rarefraction 방법으로 pH에 따른 종 출현의 기대값을 분석한 결과 역시 pH가 낮아질수록 기대값(expected number)이 낮은 것으로 나타남으로써 종 다양성 지수에 대한 유의성을 검정하였다.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.89-94
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• 2022

Triclosan (TCS) is an antimicrobial agent used in various human personal care products against both gram-positive and gram-negative bacteria. The purpose of this study was to evaluate the presence of TCS-resistant bacteria in sewage water in Peshawar, Khyber Pakhtunkhwa (KPK), Pakistan, for the first time. TCS-supplemented Luria Bertani (LB) agar was used to isolate TCS-tolerant bacteria. A total of 17 TCS-resistant isolates were randomly selected from a large pool of bacteria that showed growth on TCS-supplemented LB agar. Based on gram staining and physiochemical characteristics, the isolated strains were identified as Salmonella typhi (n = 6), Escherichia coli (n = 4), Citrobacter freundii (n = 4), Proteus mirabilis (n = 1), Enterobacter cloacae (n = 1), and Pseudomonas aeruginosa (n = 1). The Triclosan mean minimum inhibitory concentrations (MICs) for the isolates of Salmonella typhi, Escherichia coli, Citrobacter freundii, Proteus mirabilis, Enterobacter cloacae, and Pseudomonas aeruginosa were 23.66 ㎍ ml^-1, 18.75 ㎍ ml^-1, 42 ㎍ ml^-1, 32 ㎍ ml^-1, 64 ㎍ ml^-1, and 128 ㎍ ml^-1, respectively. The antibiogram revealed that all isolates were resistant to penicillin G (100%) and linezolid (100%), followed by ampicillin (94%), tetracycline (76%), tazobactam (76%), sulbactam/cefoperazone (64%), polymyxin PB (58%), amikacin (29.41%), aztreonam (29.41%), imipenem (5%), and gentamicin (5%). This is the first known study regarding the isolation of TCS-tolerant bacteria from sewage water in Peshawar, KPK, Pakistan. It was concluded that all the TCS-resistant isolates were multidrug resistant (MDR) gram-negative rod-shaped bacteria, mostly belonging to the Enterobacteriaceae family.

• 한국임상약학회지
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• 제23권1호
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• pp.20-25
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• 2013

Background & Objectives: Burn injury mortality and septic complication are frequent and well-known in burned pediatric patients. The overuse of antibiotics is the base for development of wound infection by resistant microorganisms as well as opportunist agents. Methods: We have carried out a study of the bacterial profile and antimicrobial resistance clinically important bacteria isolated from burn wound infections in children patients. The most common isolate from burn wound cultures was Pseudomonas aeruginosa (26.8%), followed by Staphylococcus aureus (25.4%), Acinetobacter baumannii (12.7%), coagulase negative staphylococcus (12.0%), Enterococcus faecium (7.7%), Escherichia coli (4.9%), Enterococcus faecalis (3.7%), Burkholderia cepacia (3.0%), Enterobacter cloacae (2.3%) and Klebsiella pneumonia (2.3%). Colistin was very significantly effective drug in gram negative organism, such as Pseudomonas aeruginosa and Acinetobacter baumannii. Results & Conclusion: The resistance rates were 65% and 98% to piperacillin, 63% and 97% to ceftazidime, 28% and 50% to levofloxacin. The most effective antibiotic in gram positive organism, such as Staphylococcus aureus, coagulase negative staphylococcus were moxifloxacin. The resistance rates were 83% and 64% to ciprofloxacin, 80% and 17% to clindamycin.

• Journal of Microbiology and Biotechnology
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• 제25권1호
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• pp.137-142
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• 2015

Trimethoprim-sulfamethoxazole (TMP-SMX) has been used for the treatment of urinary tract infections, but increasing resistance to TMP-SMX has been reported. In this study, we analyzed TMP-SMX resistance genes and their relatedness with integrons and insertion sequence common regions (ISCRs) in uropathogenic gram-negative bacilli. Consecutive nonduplicate TMP-SMX nonsusceptible clinical isolates of E. coli, K. pneumoniae, Acinetobacter spp., and P. aeruginosa were collected from urine. The minimal inhibitory concentration was determined by Etest. TMP-SMX resistance genes (sul and dfr), integrons, and ISCRs were analyzed by PCR and sequencing. A total of 45 E. coli (37.8%), 15 K. pneumoniae (18.5%), 12 Acinetobacter spp. (70.6%), and 9 Pseudomonas aeruginosa (30.0%) isolates were found to be resistant to TMP-SMX. Their MICs were all over 640. In E. coli and K. pneumoniae, sul1 and dfr genes were highly prevalent in relation with integron1. The sul3 gene was detected in E. coli. However, in P. aeruginosa and Acinetobacter spp., only sul1 was prevalent in relation with class 1 integron; however, dfr was not detected and sul2 was less prevalent than in Enterobacteriaceae. ISCR1 and/or ISCR2 were detected in E. coli, K. pneumoniae, and Acinetobacter spp. but the relatedness with TMP-SMX resistance genes was not prominent. ISCR14 was detected in six isolates of E. coli. In conclusion, resistance mechanisms for TMP-SMX were different between Enterobacteriaceae and glucose non-fermenting gram-negative bacilli. Class 1 integron was widely disseminated in uropathogenic gram-negative baciili, so the adoption of prudent use of antimicrobial agents and the establishment of a surveillance system are needed.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.816-823
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• 2022

The rapid spread of superbugs leads to the escalation of infectious diseases, which threatens public health. Endolysins derived from bacteriophages are spotlighted as promising alternative antibiotics against multi-drug resistant bacteria. In this study, we isolated and characterized the novel Salmonella typhimurium phage PBST08. Bioinformatics analysis of the PBST08 genome revealed putative endolysin ST01 with a lysozyme-like domain. Since the lytic activity of the purified ST01 was minor, probably owing to the outer membrane, which blocks accessibility to peptidoglycan, antimicrobial peptide cecropin A (CecA) was fused to the N-terminus of ST01 to disrupt the outer membrane. The resulting CecA::ST01 has been shown to have increased bactericidal activity against gram-negative pathogens including Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, and Enterobacter cloacae and the most affected target was A. baumannii. In the presence of 0.25 µM CecA::ST01, A. baumannii ATCC 17978 strain was completely killed and CCARM 12026 strain was wiped out by 0.5 µM CecA::ST01, which is a clinical isolate of A. baumannii and resistant to multiple drugs including carbapenem. Moreover, the larvae of Galleria mellonella could be rescued up to 58% or 49% by the administration of CecA::ST01 upon infection by A. baumannii 17978 or CCARM 12026 strain. Finally, the antibacterial activity of CecA::ST01 was verified using 31 strains of five gram-negative pathogens by evaluation of minimal inhibitory concentration. Thus, the results indicate that a fusion of antimicrobial peptide to endolysin can enhance antibacterial activity and the spectrum of endolysin where multi-drug resistant gram-negative pathogens can be efficiently controlled.

• 한국식품위생안전성학회지
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• 제27권2호
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• pp.109-116
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• 2012

본 연구에서는 에탄올추출과 초임계추출(SFE) 조건에 따른 생강 oleresin(GO) 추출물의 Gram 양성균(Bacillus subtilis, Staphylococcus aureus, Listeria monocytogenes)과 Gram 음성균(Pseudomonas aeruginosa, Escherichia coli)에 대한 항균활성을 살펴보았다. GO 에탄올추출은 추출물의 농도가 증가할수록 clear zone이 비례적으로 증가하였다. 이의 항균성은 Gram 양성균이 Gram 음성균보다 크게 나타났으며, 특히 Listeria monocytogenes에서 항균활성이 크게 나타났다. 생강분말과 에탄올의 추출비율이 1:6인 E-III 처리구가 항균활성이 높았다. GO 에탄올추출물의 항균성은$80^{\circ}C$ 조건에서 처리하는 것이 효과적이었고, 추출시간 (1시간~7시간)은 처리구 간에 큰 차이가 없었다. 초임계추출물에 대한 항균성은 Listeria monocytogenes에서 가장 크게 나타났다. 초임계추출물에서는 100 bar $35^{\circ}C$, 250 bar $35^{\circ}C$, 250 bar $65^{\circ}C$ 조건에서 강한 항균력을 보였다. 그리고 용매추출물의 경우 추출조건에 따라서 항균활성에 큰 차이를 나타내지 않았으나, 초임계추출물의 경우 추출압력 100 bar, 500 bar 처리구와 추출온도 $35^{\circ}C$, $65^{\circ}C$ 처리구에서 항균활성이 크게 나타났다.

• 미생물학회지
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• 제25권3호
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• pp.244-248
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• 1987

자연 발효과정중에 GRam 향성 및 음성세균의 수를 신속하고동시에 측정할 t ndlT는 방법을 검토하였다. 본 연구에서는 일반적으로 사용되고 있는 Gram 염색법을 응용하였다. 그 결과로써 Gram 염색법에의 세균수는 분광광도계에 의한 혼탁도와 A610=0.7의 범위내에서 비례관계가 성립하였다. 염색조작중 세척에 의한 균의 제거는 약 8%를 초과하지 않았다. 그리고 Escherichia coli와 Micrococcus luteus의 혼합액에서 이들의 분리 측정에 대한 표준오차는 $5.1\pm2.3$%이었다. 계수가능범위는 $5.5\times 10^{7}-1.0\times 10^{9}$세포 / ml 이었다. 그러므로 일반적인 Gram 염색법은 Gram 양성 및 음성 개체군이 혼합된 배양약에서 이들을 분별 측정하는데도 적용될 수 있다고 본다. 실제적으로, 대마침지와 김치 발효과정에서 균 생장의 동역학적 관계를 검토하였다.

• Journal of Microbiology
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• 제39권3호
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• pp.213-218
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• 2001

The treatment of Patients with bacteraemia and septicemia requires accurate and rapid identification of the pathogen so that the physician can be guided regarding the selection of the proper antimicrobial therapy. The usual procedure is to withdraw an aliquot of the positive blood culture sample for gram staining and subculturing on the media for the growth and subsequent identification, and susceptibility determinations. It was noticed that during the process some microbiologists would sniff the effluent gases that are products of metabolism and in some cases guess the identity of the bacterium. That Prompted us to engage in systematic investigation of two gram positive and two gram negative bacteria using an electronic nose that had been proven successful in distinguishing the aroma of coffee beans from different sources. The investigation was successful in illustrating the efficacy of such a device in this clinical setting to distinguish Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis. A representative set of patterns obtained with this apparatus is displayed as well. A representative set of patterns obtained with this apparatus is displayed as well. No effort was made to determine an optimal set of sensors for some specific set of bacterial metabolism gaseous products.

• Archives of Pharmacal Research
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• 제17권2호
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• pp.87-92
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• 1994

A series of $7-{2-(aminothiazol-4-yl)-2-Z-({\gamma}-lacton-3-yl)oxyiminoactamido}$ cephalosporins with various substituents at the 30position in cephem nucleus in cephem nucleus were synthesized and evaluated microbiologically. The tested compounds showed potent activities but were somewhat less active than cefotaxime or cefixime against a wide variety of Gram-positive and Gram-negative bacteria.