Publications by authors named "Ki-Hwa Kim"

This study characterized cytochrome P450 enzyme CYP154C7 from sp. PAMC26508, emphasizing its capability to hydroxylate steroids, especially at the 16α-position. The enzymatic assay of CYP154C7 demonstrated effective conversion across a pH range of 7.

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The cold-adapted bacterium Variovorax sp. PAMC28711 possesses two distinct glycoside hydrolase (GH) families of trehalase, GH15 and GH37. While numerous studies have explored bacterial trehalase, the presence of two different trehalase genes within a single strain has not been reported until now.

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Cytochrome P450 (CYP) is a heme-containing enzyme that catalyzes hydroxylation reactions with various substrate molecules. Steroid hydroxylases are particularly useful for effectively introducing hydroxyl groups into a wide range of steroids in the pharmaceutical industry. This study reports a newly identified CYP steroid hydroxylase (CYP106A6) from the bacterium sp.

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Article Synopsis
  • The bacterial CYP105 family contributes to the synthesis of secondary metabolites and helps in processing harmful substances.
  • This study highlights CYP105D18 as the first bacterial enzyme identified for N-oxidation, showcasing impressive catalytic efficiency for papaverine.
  • The findings suggest that CYP105D18's structure and high tolerance for hydrogen peroxide could be leveraged for future biotechnological applications in pharmaceuticals.
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7α-Hydroxysteroid dehydrogenase (7α-HSDH) catalyzes the dehydrogenation of a hydroxyl group at the 7α position in steroid substrates using NAD or NADP as a co-factor. Although studies have determined the binary and ternary complex structures, detailed structural changes induced by ligand and co-factor binding remain unclear, because ligand-free structures are not yet available. Here, we present the crystal structure of apo 7α-HSDH from Escherichia coli (Eco-7α-HSDH) at 2.

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Bacterial cytochrome P450 (CYP) enzymes are responsible for the hydroxylation of diverse endogenous substances with a heme molecule used as a cofactor. This study characterized two CYP154C3 proteins from sp. W2061 (CYP154C3-1) and sp.

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The characterization of cytochrome P450 CYP125A13 from was conducted using cholesterol as the sole substrate. The in vitro enzymatic assay utilizing putidaredoxin and putidaredoxin reductase from revealed that CYP125A13 bound cholesterol and hydroxylated it. The calculated K value, catalytic conversion rates, and Km value were 56.

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Self-sufficient P450s, due to their fused nature, are the most effective tools for electron transfer to activate C-H bonds. They catalyze the oxygenation of fatty acids at different omega positions. Here, two new, self-sufficient cytochrome P450s, named CYP102A15 and CYP102A170, from polar sp.

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Bacterial cytochrome P450 (CYP) enzymes are involved in the hydroxylation of various endogenous substrates while using a heme molecule as a cofactor. CYPs have gained biotechnological interest as useful biocatalysts capable of altering chemical structures by adding a hydroxyl group in a regiospecific manner. Here, we identified, purified, and characterized two CYP154C4 proteins from Streptomyces sp.

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CYP154C8 from Streptomyces sp. has been identified as a new cytochrome P450 with substrate flexibility towards different sets of steroids. In vitro treatment of these steroids with CYP154C8 revealed interesting product formation patterns with the same group of steroids.

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Bacterial cytochrome P450 (CYP) steroid hydroxylases are effectively useful in the pharmaceutical industry for introducing hydroxyl groups to a wide range of steroids. We found a putative CYP steroid hydroxylase (CYP106A2) from the bacterium sp. PAMC 23377 isolated from Kara Sea of the Arctic Ocean, showing 94% sequence similarity with CYP106A2 ( ATCC 13368).

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Microbacterium sp. strain PAMC28756, of the family Microbacteriaceae, was isolated from Stereocaulon sp., an Antarctic lichen.

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Although the five basic taste qualities-sweet, sour, bitter, salty and umami-can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level.

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