The folate receptor, like many glycosylphosphatidylinositol-anchored proteins, is found associated with membrane domains that are insoluble in Triton X-100 at low temperature and that are enriched in cholesterol and sphingolipids. Depletion of cellular cholesterol has been shown to inhibit vitamin uptake by this receptor (Chang, W. -J., Rothberg, K. G., Kamen, B. A., and Anderson, R. G. W. (199...

Direct current polarography and differential pulse polarographic methods have been developed for the qualitative as well as quantitative analysis of vitamin B1, B2 and B6. Thiamin (vitamin B1) produced a well-defined wave in 0.1 M KCl at pH 5.2 with E(1/2)=-1.2 V and E(p)=-1.22 V versus saturated calomal electrode (SCE). Riboflavin (vitamin B2) gave two distinct waves in Britton Robinson buffer...

Vitamin B1 (thiamin) is an essential compound in all organisms acting as a cofactor in key metabolic reactions and has furthermore been implicated in responses to DNA damage and pathogen attack in plants. Despite the fact that it was discovered almost a century ago and deficiency is a widespread health problem, much remains to be deciphered about its biosynthesis. The vitamin is composed of a t...