Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: UMLS:C0027960 (
mole
)
21,279
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
GDP-D-mannose dehydratase
(
GMD
) catalyzes the first step of the pathway that converts GDP-D-mannose to GDP-L-fucose in bacteria, plants and mammals. Recently, the gene coding for
GMD
has been identified and sequenced in E. coli. Based on this sequence, we have expressed and purified
GMD
in E. coli as a glutathione transferase (GST) fusion protein. The fused GST-
GMD
protein and the thrombin-cleaved
GMD
were then characterized. The catalytically active form of both enzyme species seems to be a hexamer of 410 and 250 kDa, respectively. The GST-
GMD
fusion protein has a Km of 0.22 +/- 0.04 mM and a specific activity of 2.3 +/- 0.2 micromol/h/mg. Ca2+ and Mg2+ activate
GMD
, while GDP-L-beta-fucose, the end-product of the pathway, inhibits it specifically. The GST-
GMD
fusion protein contains one
mole
of tightly bound NADP+ per
mole
of hexamer. Apparently, this NADP+ is involved in the catalytic mechanism of
GMD
.
...
PMID:Expression, purification and characterization of GDP-D-mannose 4,6-dehydratase from Escherichia coli. 925 4