-transparent.png){kind=logo}
To elucidate the biosynthesis of 25-hydroxyvitamin D3-26,23-lactone, two known metabolites of 25-hydroxyvitamin D3--23,25-dihydroxyvitamin D3 and 25,26-dihydroxyvitamin D3--were incubated individually with kidney homogenate prepared from vitamin D-supplemented chickens, a preparation known to produce the lactone from 25-hydroxyvitamin D3. The 25-hydroxyvitamin D3-26,23-lactone produced in vitro was then separated, purified, identified, and quantitated by consecutive straight-phase and reverse-phase high-performance liquid chromatography. 23,25-Dihydroxyvitamin D3 is a far better substrate for production of 25-hydroxyvitamin D3-26,23-lactone than is 25,26-dihydroxyvitamin D3. Production of lactone is highly selective for the natural 23(S)-hydroxy-23,25-dihydroxyvitamin D3 while both epimers of 25,26-dihydroxyvitamin D3 resulted in small amounts of product comigrating with natural lactone. It appears that 23(S),25-dihydroxyvitamin D3, but not 25,26-dihydroxyvitamin D3, is a natural precursor in the synthesis of 25-hydroxyvitamin D3-26,23-lactone; this result also implies that the configuration of the lactone at C-23 is S.
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
November 1981,
FEBS letters,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
August 1982,
The Journal of biological chemistry,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
December 1981,
Archives of biochemistry and biophysics,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
February 1982,
FEBS letters,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
January 1984,
The Journal of biological chemistry,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
February 1995,
Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
October 1985,
Archives of biochemistry and biophysics,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
August 1983,
Journal of chromatography,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
March 1982,
FEBS letters,
Y Tanaka, and
H F DeLuca, and
H K Schnoes, and
N Ikekawa, and
T Eguchi
August 1984,
Biochemistry,
