Synthesis of 4-pyridoxolactone from pyridoxine using a combination of transformed Escherichia coli cells.

We developed a simple and efficient synthesis for 4-pyridoxolactone starting with pyridoxine and using a whole-cell biotransformation by two transformed Escherichia coli cell types. One set of transformed cells expressed pyridoxine 4-oxidase, catalase, and chaperonin, while the second set expressed pyridoxal 4-dehydrogenase. With this combination of cells, pyridoxine was first oxidized to pyridoxal, which was then dehydrogenated to 4-pyridoxolactone by pyridoxine 4-oxidase and pyridoxal 4-dehydrogenase, respectively.

Chemical speciation of insulinomimetic VO(IV) complexes of pyridine-N-oxide derivatives: binary and ternary systems.

In order to estimate the impact of the low-molecular-mass (l.m.m.

Structure-dependent metallokinetics of antidiabetic vanadyl-picolinate complexes in rats: studies on solution structure, insulinomimetic activity, and metallokinetics.

The insulinomimetic effect of vanadium is the most remarkable and important among its several biological actions. Vanadyl ion (+4 oxidation state of vanadium) and its complexes have been found to normalize the blood glucose levels of both type 1 and 2 diabetic animals. We have developed insulinomimetic vanadyl complexes having different coordination modes, emphasizing the possible usefulness of vanadyl-picolinate [VO(pa)(2)] and its related complexes with the VO(N(2)O(2)) coordination mode.