• Journal of Microbiology and Biotechnology
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• 제17권7호
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• pp.1169-1176
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• 2007

Genes encoding proteins responsible for limonene catabolism were cloned from a limonene-degrading microorganism, Enterobacter cowanii 6L, which was isolated from citron (Citrus junos) peel. The 8.6, 4.7, and 7.7 kb fragments (CD3, CD4, and CD6) of E. cowanii 6L chromosomal DNA that confer to E. coli the ability to grow on limonene have been cloned and their corresponding DNA sequences were determined. Nine open reading frames (ORFs) were identified, and the four ORFs (921 bp of CD3-2; 1,515 bp of CD4-1; 1,776 bp of CD6-1; and 1,356 bp of CD6-2) that encode limonene hydroxylase were confirmed by independently expressing these genes in E. coli. FAD and NADH were found to stimulate the hydroxylation reaction if added to cell extracts from E. coli recombinants, and multiple compounds (linalool, dihydrolinalool, perillyl alcohol, (${\alpha}-terpineol$, and ${\gamma}-terpineol$) were the principal products observed. Our results suggest that the isolate E. cowanii 6L has a broad metabolic capability including utilization of limonene. This broad metabolic ability was confirmed by identifying four novel limonene hydroxylase functional ORFs in E. cowanii 6L.

• 한국미생물·생명공학회지
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• 제35권3호
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• pp.191-195
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• 2007

탄닌 분해균 선발배지를 이용하여 탄닌 분해활성 보유 유산균을 발효 침채류로부터 분리하는 과정에서 오이소박이, 파김치, 총각김치로부터 다당류로 추정되는 점질물질을 생산하는 균주 4종을 선발하였다. 이들 균주의 165 rDNA 염기서열에 의한 계통유전학적 동정 결과, CK31은 Enterobacter cowanii, CK32는 Escherichia senegalensis, YK5는 Enterobacter asburiae, GK23은 Enterobacter ludwigii와 99% 이상의 매우 높은 상동성을 나타내었다. 가장 많은 양의 점질 물질을 세포 외로 생성하는 CK3l 균주는 rhamnose, fucose, arabinose, mannose, galactose, glucose의 중성당 조성을 가지고 있는 분자량 약 420 kDa heteropolysaccharide를 생산하는 것으로 나타났다.