Publications by authors named "Jae Kap Jeong"

Targeting hair follicle regeneration has been investigated for the treatment of hair loss, and fundamental studies investigating stem cells and their niche have been described. However, knowledge of stem cell metabolism and the specific regulation of bioenergetics during the hair regeneration process is currently insufficient. Here, we report the hair regrowth-promoting effect of a newly synthesized novel small molecule, IM176OUT05 (IM), which activates stem cell metabolism.

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Streptococcus pneumoniae is a causative agent of high morbidity and mortality. Although sugar moieties have been recognized as ligands for initial contact with the host, only a few exoglycosidases have been reported to occur in S. pneumoniae.

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The alpha-subunit of tryptophan synthase (alphaTS) catalyzes the cleavage of indole-3-glycerol phosphate to glyceraldehyde-3-phosphate and indole, which is used to yield the amino acid tryptophan in tryptophan biosynthesis. Here, we report the first crystal structures of wild-type and double-mutant P28L/Y173F alpha-subunit of tryptophan synthase from Escherichia coli at 2.8 and 1.

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The post-polyketide synthase modification of geldanamycin (1) biosynthesis is of interest as a means of introducing structural diversity into the compound. From the inactivation of a gene encoding carbamoyltransferase, we demonstrated that the C-17 hydroxylation and the C-21 oxidation precede O-carbamoylation and that the hypothetical progeldanamycin does not possess a double bond at C-4 and C-5. More importantly, our result revealed new intermediates 4,5-dihydro-7-O-descarbamoyl-7-hydroxygeldanamycin (3) and 4,5-dihydrogeldanamycin (5), indicating that O-carbamoylation occurs prior to the C-4,5 cis double bond formation in geldanamycin biosynthesis.

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Tryptophan synthase alpha-subunit (alphaTS) catalyzes the cleavage of indole-3-glycerolphosphate to glyceraldehyde-3-phosphate and indole, which is channelled to the active site of the associated beta-subunit (betaTS), where it reacts with serine to yield the amino acid tryptophan in tryptophan biosynthesis. The alphaTS from Escherichia coli is a 268 amino-acid protein with no disulfide bonds or prosthetic groups. Although the crystallization of the subunits from E.

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The fluorescence of tyrosine has been used to monitor a folding process of tryptophan synthase alpha-subunit from Escherichia coli, because this protein has 7 tyrosines, but not tryptophan. Here to assess the contribution of each Tyr to fluorescence properties of this protein during folding, mutant proteins in which Tyr was replaced with Phe were analyzed. The result shows that a change of Tyr fluorescence occurring during folding of this protein is contributed to approximately 40% each by Tyr(4) and Tyr(115), and to the remaining approximately 20% by Tyr(173) and Tyr(175).

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