• Journal of Microbiology
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• 제43권1호
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• pp.49-53
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• 2005

Putative genes for a two-component signal transduction system (akbS and akbT) were detected near the alkylbenzene-degrading operon of Rhodococcus sp. DK17. Sequence analysis indicates that AkbS possesses potential ATP-binding and histidine autophosphorylation sites in the N- and C-terminal regions, respectively, and that AkbT has a typical response regulator domain. Mutant analysis combined with RT-PCR experiments further shows that AkbS is required to induce the expression of o-xylene dioxygenase in DK17.

• 한국환경농학회지
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• 제40권4호
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• pp.248-259
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• 2021

BACKGROUND: Contaminated water was a major source of food-borne pathogens in various recent fresh produce-related outbreaks. This study was conducted to investigate the microbial contamination level and correlations between the level of sanitary indicator bacteria and the detection ratio of pathogens in agricultural water by logistic regression analysis. METHODS AND RESULTS: Agricultural water was collected from 457 sites including surface water (n=300 sites) and groundwater (n=157 sites) in South Korea from 2018 to 2020. Sanitary indicator bacteria (total coliform, fecal coliform, and Escherichia coli) and food-borne pathogens (pathogenic E. coli, E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were analyzed. In surface water, the coliform, fecal coliform, and E. coli were 3.27±0.89 log CFU/100 mL, 1.90±1.19 log CFU/100 mL, and 1.39±1.26 log CFU/100 mL, respectively. For groundwater, three kinds of sanitary indicators ranged in the level from 0.09 - 0.57 log CFU/100 mL. Pathogenic E. coli, Salmonella and Listeria monocytogenes were detected from 3%-site, 1.5%- site, and 0.6%-site water samples, respectively. According to the results of correlations between the level of sanitary indicator bacteria and the detection ratio of pathogens by logistic regression analysis, the probability of pathogen detection increased individually by 1.45 and 1.34 times as each total coliform and E. coli concentration increased by 1 log CFU/100mL. The accuracy of the model was 70.4%, and sensitivity and specificity were 81.5% and 51.7%, respectively. CONCLUSION(S): The results indicate the need to manage the microbial risk of agricultural water to enhance the safety of fresh produce. In addition, logistic regression analysis is useful to analyze the correlation between the level of sanitary indicator bacteria and the detection ratio of pathogens in agricultural water.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2000년도 International Symposium on Bioinformatics
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• pp.83-85
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• 2000

A lot of microbial genome sequencing projects is being done in many genome centers around the world, since the first genome, Haemophilus influenzae, was sequenced in 1995. The deluge of microbial genome sequence data demands new and highly automatic data flow system in order for genome researchers to manage and analyze their own bulky sequence data from low-level to high-level. In such an aspect, we developed the automatic data management system for microbial genome projects, which consists mainly of local database, analysis programs, and user-friendly interface. We designed and implemented the local database for large-scale sequencing projects, which makes systematic and consistent data management and retrieval possible and is tightly coupled with analysis programs and web-based user interface, That is, parsing and storage of the results of analysis programs in local database is possible and user can retrieve the data in any level of data process by means of web-based graphical user interface. Contig assembly, homology search, and ORF prediction, which are essential in genome projects, make analysis programs in our system. All but Contig assembly program are open as public domain. These programs are connected with each other by means of a lot of utility programs. As a result, this system will maximize the efficiency in cost and time in genome research.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.19.1-19.12
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• 2021

Objectives: The purpose of this study was to conduct a systematic review and meta-analysis of in vitro studies regarding the effectiveness of reciprocating and rotary instrumentation on microbial reduction in root canals. Materials and Methods: PubMed, Scopus, Web of Science, the Cochrane Library, and the gray literature were searched through December 2019. Studies comparing the influence of reciprocating and rotary instrumentation on the removal of microorganisms from root canals that quantified the antimicrobial effect were included. Data extraction was completed using a systematic form for data collection. The risk of bias of the studies was evaluated. Standardized mean differences (SMDs) and confidence intervals (CIs) were calculated using a random effects meta-analysis. Results: Seventeen in vitro studies were included in this systematic review, of which 7 provided adequate data for inclusion in the meta-analysis. Both reciprocating and rotary systems were similarly effective in reducing the microbial load in infected root canals (SMD [95% CI], 0.0481 [-0.271, 0.367]). Three studies showed a low risk of bias, whereas most of the studies (82%) presented a medium risk. Conclusions: Although both techniques decrease the microbial content (with reductions of 23.32%-88.47% and 23.33%-89.86% for reciprocating and rotary instrumentation, respectively), they are not able to provide complete disinfection of root canals.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2003년도 2003 Annual Meeting, BioExhibition and International Symposium
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• pp.91-94
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• 2003

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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• pp.133-134
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• 2001

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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• pp.20-25
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• 2001

• Korean Chemical Engineering Research
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• 제48권2호
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• pp.147-156
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• 2010

폐가스 처리용 바이오필터의 핵심 요소 기술은 생촉매(미생물), 담체, 설계 운전 기술 및 진단 관리 기술이다. 특히, 바이오필터의 성능은 부하 조건과 바이오필터 내 미생물 군집 구조에 의해 영향을 받는다. 지금까지 바이오필터의 미생물 연구는 대부분 배양법을 기초로 하여 수행되어 왔으나, 최근에 보다 신속하고 정확하게 미생물 군집을 분석할 수 있는 방법들이 제시되고 있다. 본 논문에서는 생리적, 생화학적 및 분자생물학적 미생물 군집 분석 방법과 이를 활용한 바이오필터의 미생물 군집 특성을 조사한 연구사례를 소개하고, 미생물 군집 분석법의 바이오필터에 적용 가능성에 대해 고찰하였다. Community-level physiological profile 방법은 시료 중에 포함된 종속영양미생물의 탄소기질 이용능력을 기반으로 군집 특성을 조사하는 것이며, Phospholipid fatty acid analysis는 미생물 세포막 지방산을 분석하여 군집 특성을 조사하는 방법이다. 환경시료로부터 직접 추출한 DNA를 활용하는 분자생물학적 분석법에는 "partial community DNA analysis"와 "whole community DNA analysis"가 있다. 전자의 방법은 PCR 과정에 의해 증폭시킨 염기서열을 분석하는 것으로 ribosomal operon 유전자가 가장 많이 활용되었다. 이 방법은 다시 PCR fragment cloning 및 genetic fingerprinting으로 구분되며, genetic fingerprinting 방법으로는 denaturing gradient gel electrophoresis, terminal-restriction fragment length polymorphism, ribosomal intergenic spacer analysis 및 random amplified polymorphic DNA 방법으로 세분화된다. 추출된 전체 군집의 DNA를 분석하는 방법에는 total genomic cross-DNA hybridization, 총 추출 DNA의 열 변성/재결합 방법 및 밀도구배를 이용하여 추출한 DNA를 분획화하는 방법 등이 있다.

• 한국환경과학회지
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• 제11권1호
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• pp.63-68
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• 2002

In this study, we examined statistical analysis between sewage plant operations parameters and effluent quality We got six components from principle component analysis of the operation parameters and secondary effluent quality. 91.8% of the total variance was explained by the six components. The components were identified in the following order : 1) organic matter removal by aeration basin microbe, 2) settleability on secondary clarifier load, 3) removal of nutrients, 4) microbial number increasement and species diversity, 5) microbial activity in aeration basin, 6) oxidation in aeration basin.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.185-193
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• 2002

We have developed GComp as an analysis tool for comparative analysis of microbial genomes. Thetool uses BLAST or FASTA as a preprocessing program for local alignments, parses the homology search results, and generates tables and files to show homology relationship between two genomes at a glance. The interface for graphical representation of the comparative genomic analysis has been also implemented. Through analysis of a few pairs of microbial genome sequences, the program has been proved to be practically useful and a few additional features have been devised and designed, which will be added in the further development.