• 미생물학회지
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• 제23권4호
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• pp.302-308
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• 1985

L-Ascorbic aciddm ltodcp 산화분해과정중 ${\alpha}$-ketoaldehyde의 한 종류인 3,4,5-trihydroxy-2-keto-L-valeral-dehyde(L-xylosone)가 형성된다는 사실을 핵자기공명스펙트럼분석법으로 확인하였다. 이 물질은 glyoxalase system에 의해 L-xylonic acid로 변환되고 계속해서 L-erythroascorbic acid로 산화된다. 이러한 근거 위에서 vitamin C의 분해과정이 vitamic C 이외의 두종류의 ${\gamma}$-lactones-과 3종류의 ${\alpha}$-ketoaldehydes로 구성된 분해경로를 갖는다는 사실을 제안하였다.

• Journal of Microbiology and Biotechnology
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• 제27권1호
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• pp.77-83
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• 2017

Lignocellulosic biomass represents a potentially large resource to supply the world's fuel and chemical feedstocks. Enzymatic bioconversion of this substrate offers a reliable strategy for accessing this material under mild reaction conditions. Owing to the complex nature of lignocellulose, many different enzymatic activities are required to function in concert to perform efficient transformation. In nature, large multienzyme complexes are known to effectively hydrolyze lignocellulose into constituent monomeric sugars. We created artificial complexes of enzymes, called rosettazymes, in order to hydrolyze glucuronoxylan, a common lignocellulose component, into its cognate sugar ${\small{D}}$-xylose and then further convert the ${\small{D}}$-xylose into ${\small{D}}$-xylonic acid, a Department of Energy top-30 platform chemical. Four different types of enzymes (endoxylanase, ${\alpha}$-glucuronidase, ${\beta}$-xylosidase, and xylose dehydrogenase) were incorporated into the artificial complexes. We demonstrated that tethering our enzymes in a complex resulted in significantly more activity (up to 71%) than the same amount of enzymes free in solution. We also determined that varying the enzyme composition affected the level of complex-related activity enhancement as well as overall yield.