• Journal of Microbiology and Biotechnology
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• 제19권5호
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• pp.474-481
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• 2009

A novel microorganism, designated as LG12, was isolated from soil based on its ability to use acrylic acid as the sole carbon source. An electron microscopic analysis of its morphological characteristics and phylogenetic classification by 16S rRNA homology showed that the LG12 strain belongs to Rhodococcus erythropolis. R. erythropolis LG12 was able to metabolize a high concentration of acrylic acid (up to 40 g/l). In addition, R. erythropolis LG12 exhibited the highest acrylic acid-degrading activity among the tested microorganisms, including R. rhodochrous, R. equi, R. rubber, Candida rugosa, and Bacillus cereus. The effect of the culture conditions of R. erythropo/is LG12 on the production of 3-hydroxypropionic acid (3HP) from acrylic acid was also examined. To enhance the production of 3HP, acrylic acid-assimilating activity was induced by adding 1 mM acrylic acid to the culture medium when the cell density reached an $OD_{600}$ of 5. Further cultivation of R. erythropo/is LG 12 with 40 g/l of acrylic acid resulted in the production of 17.5 g/l of 3HP with a molar conversion yield of 44% and productivity of 0.22 g/l/h at $30^{\circ}C$ after 72 h.

• KSBB Journal
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• 제31권4호
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• pp.246-255
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• 2016

Co-production of 3-hydroxypropionic acid (3-HP) and 1,3-propanediol (1,3-PDO) was suggested as an innovative strategy to overcome several limitations occurring in the single production of 3-HP from glycerol. In this study, two new isolates of Klebsiella pneumoniae, which produce less lipopolysaccharide (LPS) thus considered less pathogenic than K. pneumoniae DSM 2026, were compared and evaluated for their potential for the co-production of 3-HP and 1,3-PDO. The newly isolated strains showed significantly faster sedimentation rate than DSM, which should be beneficial for downstream processing. Analysis of genome sequences of the isolates confirmed the presence of all genes necessary for glycerol assimilation, 1,3-PDO production and biosynthesis of coenzyme $B_{12}$. Co-production yield was highest under anaerobic condition while cell growth was highest under aerobic condition. Both strains showed similarly good performance for the co-production although J2B gave the slightly higher co-production yield of 0.80 mol/mol than GSC021 (0.75 mol/mol). The evaluation of the newly developed strains presented here should be useful in designing similar evaluation experiments for other microorganisms.

• Journal of Microbiology and Biotechnology
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• 제32권2호
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• pp.170-175
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• 2022

3-Hydroxypropionic acid (3HP) is a platform chemical and can be converted into other valuable C3-based chemicals. Because a large amount of glycerol is produced as a by-product in the biodiesel industry, glycerol is an attractive carbon source in the biological production of 3HP. Although eight 3HP-producing aldehyde dehydrogenases (ALDHs) have been reported so far, the low conversion rate from 3-hydroxypropionaldehyde (3HPA) to 3HP using these enzymes is still a bottleneck for the production of 3HP. In this study, we elucidated the substrate binding modes of the eight 3HP-producing ALDHs through bioinformatic and structural analysis of these enzymes and selected protein engineering targets for developing enzymes with enhanced enzymatic activity against 3HPA. Among ten AbKGSADH variants we tested, three variants with replacement at the Arg281 site of AbKGSADH showed enhanced enzymatic activities. In particular, the AbKGSADH^R281Y variant exhibited improved catalytic efficiency by 2.5-fold compared with the wild type.

• 대한유전성대사질환학회지
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• 제21권1호
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• pp.22-27
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• 2021

프로피온산혈증은 PCCA 및 PCCB 유전자의 돌연변이로 발생하며 대사산물의 축적으로 신생아기부터 근긴장 저하, 구토, 케톤산증, 고암모니아혈증, 경련 등이 나타나 사망에 이를 수 있고, 비교적 후기에 신경학적 증상과 함께 발현하는 경과를 보이기도 한다. 저자들은 특별한 과거력 없이 지내던 중 확장성 심근병증이 확인된 16세 남아에서 유전자 검사로 프로피온산혈증이 진단된 1례를 보고하는 바이다.

• 대한유전성대사질환학회지
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• 제16권1호
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• pp.47-51
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• 2016

프로피온산혈증은 상염색체 열성유전에 의해 발생하는 질환으로, 혈중에 암모니아, 독성 물질 등이 축적되어 경한 증상에서부터 사망에까지 이르는 질환이다. 유병률은 50,000-100,000명당 1명이다. PCCA 또는 PCCB 유전자의 돌연변이로 발생하며, 이것을 규명하는 것이 가장 확실한 진단 방법이다. 두 유형에 따른 임상경과 차이는 뚜렷하게 밝혀져 있지 않다. 발병 시기에 따라 신생아기형과 후기형으로 나눌 수 있다. 증상 발현의 원인은 이화작용을 강화시키는 감염, 스트레스, 변비, 단백질의 과도한 섭취 등이며, 운동실조, 이상행동, 식욕부진, 주기적 구토, 성장장애, 신경발달이상 등의 광범위한 임상 경과를 보인다. 정확한 진단과 조속한 초기 치료가 환자의 생존율 및 신경 발달 장애 여부에 중요한 요소이다. 본 증례는 고암모니아혈증 및 대사산증이 심하지 않았으나 조기에 대사성 질환을 염두에 두고 PCCA와 PCCB 유전자의 돌연변이를 분석하여 프로피온산혈증을 진단하고 적극적인 금식 및 수액 치료와 진단을 통해 신체 발달 및 운동 및 치명적인 신경학적 장애 없이 성장한 고무적인 사례로 이를 보고하는 바이다.