Active transport activities of free B-6 vitamers in various yeast strains.
Active transport activities of free B-6 vitamers in 35 strains of 8 genera of yeast were measured by isocratic reverse-phase HPLC. Many but not all strains transported pyridoxamine and/or pyridoxine. The active transport activities in some yeast strains tested were completely inhibited by amiloride (0.5 mM). In contrast to cells so far studied, yeast cells showed a novel character in metabolism of accumulated B-6 vitamers: the phosphorylation of the free B-6 vitamers was regulated at a low level. There was no apparent correlation between the presence of the active transport activity in yeasts and the requirement of vitamin B-6 for their growth.
Yagi
T
T
Department of Bioresources Science, Faculty of Agriculture, Kochi University, Japan.
Kim
Y
Y
Hiraoka
Y
Y
Tanouchi
A
A
Yamamoto
T
T
Yamamoto
S
S
D000584:Amiloride / Q000494:pharmacology; D001693:Biological Transport, Active / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004232:Diuretics / Q000494:pharmacology; D010766:Phosphorylation; D011730:Pyridoxal / Q000378:metabolism*; D011733:Pyridoxamine / Q000378:metabolism*; D011736:Pyridoxine / Q000378:metabolism*; D013045:Species Specificity; D015003:Yeasts / Q000187:drug effects / Q000378:metabolism*
D004232:Diuretics; D011730:Pyridoxal; D011733:Pyridoxamine; D000584:Amiloride; D011736:Pyridoxine