Investigation of Vitamin D2 and Vitamin D3 Hydroxylation by Kutzneria albida

The active vitamin D metabolites 25-OH-D and 1 alpha,25-(OH)(2)-D play an essential role in controlling several cellular processes in the human body and are potentially effective in the treatment of several diseases, such as autoimmune diseases, cardiovascular diseases and cancer. The microbial synthesis of vitamin D-2 (VD2) and vitamin D-3 (VD3) metabolites has emerged as a suitable alternative to established complex chemical syntheses. In this study, a novel strain, Kutzneria albida, with the ability to form 25-OH-D-2 and 25-OH-D-3 was identified. To further improve the conversion of the poorly soluble substrates, several solubilizers were tested. 100-fold higher product concentrations of 25-OH-D-3 and tenfold higher concentrations of 25-OH-D-2 after addition of 5 % (w/v) 2-hydroxypropyl beta-cyclodextrin (2-HP beta CD) were reached. Besides the single-hydroxylation products, the human double-hydroxylation products 1,25-(OH)(2)-D-2 and 1,25-(OH)(2)-D-3 and various other potential single- and double-hydroxylation products were detected. Thus, K. albida represents a promising strain for the biotechnological production of VD2 and VD3 metabolites.

Automated summary

The study identified a novel strain, Kutzneria albida, capable of producing 25-OH-D-2 and 25-OH-D-3, with significantly increased product concentrations after the addition of 2-hydroxypropyl beta-cyclodextrin. This suggests that K. albida is a promising candidate for the biotechnological production of VD2 and VD3 metabolites.