• 대한환경공학회지
• /
• 제27권9호
• /
• pp.911-916
• /
• 2005

본 연구에서는 하수가 관거를 유하하면서 물리, 화학, 생물학적 반응을 통하여 오염물질이 제거되는 특성을 평가하기 위하여 실제 관거를 대상으로 상, 하류수질변화를 분석하고 관거 퇴적물의 입경변화와 오염물함유량을 평가하였다. 상류와 하류가 2.4 km 떨어진 두 지점에서 24시간 연속 채취된 시료에 대한 DOC 분석결과 상하류의 농도차이는 $-5.8{\sim}18.6\;mg/L$의 범위를 보였다. 상류측 평균 DOC농도를 기준으로 8.4%가 감소하였으며, 관거길이당 감소율은 2.3 mg/L/km, 평균체류시간에 의한 감소율은 0.093 mg/L/min으로 나타났다. SS의 경우 상류와 하류간의 수질차는 $-10.5{\sim}34.6\;mg/L$, 평균 SS 농도차는 13.3 mg/L, 상류수질을 기준으로 10.4%정도 감소하였으며 관거길이당 감소율은 5.5 mg/L/km, 평균체류시간에 의한 감소율은 0.22 mg/L/min으로 DOC에 비하여 약 2배 정도 높은 감소율을 나타내었다. 침입수/유입수를 고려하여 DOC, SS의 누적오염부하를 비교한 결과, DOC의 경우 일누적오염부하를 기준으로 상류 1,230 kg/d, 하류 1,167 kg/d으로 5.2%가 감소하였고, SS의 경우 상류 2,371kg/d, 하류는 2,186 kg/d로 7.8% 감소하였다. 이러한 결과는 하수를 처리장까지 수송하튼 관거시스템내에서 오염부하의 일부가 제거되고 있음을 보여주는 것이며, 하수처리장의 설계 및 운영시 관거를 통한 감소영향을 고려하는 것이 필요함을 알 수 있다.

• 한국생물정보학회:학술대회논문집
• /
• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
• /
• pp.147-150
• /
• 2005

Proper PCR primer design determines the success or failure of Polymerase Chain Reaction (PCR) reactions. In this project, we develop GENE-PRIMER, a genomes specific PCR primer design program that is amenable to a genome-wide scale. To achieve this, we incorporated various parameters with biological significance into our program, namely, primer length, melting temperature of primers Tm, guanine/cytosine (GC) content of primer, homopolymeric runs in primer and self-hybridization tendency of primer. In addition, BLAST algorithm is utilized for the purpose of primer specificity check. In summary, selected primers adhered to both physico-chemical criteria and also display specificity to intended binding site in the genome.

• 한국미생물생명공학회:학술대회논문집
• /
• 한국미생물생명공학회 2004년도 Annual Meeting BioExibition International Symposium
• /
• pp.60-61
• /
• 2004

Metabolic engineering is now a well established discipline, used extensively to determine and execute rational strategies of strain development to improve the performance of micro-organisms employed in industrial fermentations. The basic principle of this approach is that performance of the microbial catalyst should be adequately characterised metabolically so as to clearlyidentify the metabolic network constraints, thereby identifying the most probable targets for genetic engineering and the extent to which improvements can be realistically achieved. In order to harness correctly this potential, it is clear that the physiological analysis of each strain studied needs to be undertaken under conditions as close as possible to the physico-chemical environment in which the strain evolves within the full-scale process. Furthermore, this analysis needs to be undertaken throughoutthe entire fermentation so as to take into account the changing environment in an essentially dynamic situation in which metabolic stress is accentuated by the microbial activity itself, leading to increasingly important stress response at a metabolic level. All too often these industrial fermentation constraints are overlooked, leading to identification of targets whose validity within the industrial context is at best limited. Thus the conceptual error is linked to experimental design rather than inadequate methodology. New tools are becoming available which open up new possibilities in metabolic engineering and the characterisation of complex metabolic networks. Traditionally metabolic analysis was targeted towards pre-identified genes and their corresponding enzymatic activities within pre-selected metabolic pathways. Those pathways not included at the onset were intrinsically removed from the network giving a fundamentally localised vision of pathway functionality. New tools from genome research extend this reductive approach so as to include the global characteristics of a given biological model which can now be seen as an integrated functional unit rather than a specific sub-group of biochemical reactions, thereby facilitating the resolution of complexnetworks whose exact composition cannot be estimated at the onset. This global overview of whole cell physiology enables new targets to be identified which would classically not have been suspected previously. Of course, as with all powerful analytical tools, post-genomic technology must be used carefully so as to avoid expensive errors. This is not always the case and the data obtained need to be examined carefully to avoid embarking on the study of artefacts due to poor understanding of cell biology. These basic developments and the underlying concepts will be illustrated with examples from the author's laboratory concerning the industrial production of commodity chemicals using a number of industrially important bacteria. The different levels of possibleinvestigation and the extent to which the data can be extrapolated will be highlighted together with the extent to which realistic yield targets can be attained. Genetic engineering strategies and the performance of the resulting strains will be examined within the context of the prevailing experimental conditions encountered in the industrial fermentor. Examples used will include the production of amino acids, vitamins and polysaccharides. In each case metabolic constraints can be identified and the extent to which performance can be enhanced predicted