Vitamin K1 [BSA]

Photoactivities of four natural or natural-derivatized vitamin K (VK) species were investigated by using a combination of theoretical computational modeling, prediction, and specially designed experimental tests. The results revealed that these VK compounds are photoactive in the generation of reactive oxygen species of hydroxyl radicals and singlet oxygen under daylight, UVA, and UVB irradiations. Two possible photoreaction paths exist in an environment of good or poor hydrogen donors. Vitamin K-3 (VK3), as an aromatic naphthoquinone compound, was predicted and demonstrated as the most effective photoactive agent under a broad range of UV-vis wavelengths and in production of both hydroxyl radicals and singlet oxygen. VK1 and VK2 are less active than VK3 due to the existence of double bonds in their side chains of naphthoquinone. VK4 is different in photoactivity due to the loss of an aromatic ketone structure. As an example, VK3 was tested against Gram-negative Escherichia coli and Gram-positive Listeria innocua under daylight irradiation and exhibited complete kill of Escherichia coli (six log reduction in 60 min of daylight exposure) and Listeria innocua (five log reduction in 90 min of daylight exposure). In addition, VK3 retained its high bactericidal efficacy toward both Escherichia coli and Listeria innocua after seven times of repeated daylight exposures, indicating excellent reusability as a green biocide. This work provides insight into the development of green and sustainable photoinduced antimicrobial materials for biomedical and food safety applications.

We have isolated five monoclonal IgG anti-P,-beta(2)-glycoprotein-1 (anti-P,G-l) and anti-prothrombin Fab from a patient with autoantibodies to oxidized low-density lipoproteins by phage display method, analysis of their binding specificity revealed that all three beta(2)GP-1-enriched mAbs (B14, B22, B27) reacted with beta(2)GP-1 while both prothrombin-isolated mAbs (P11 and P13) reacted with prothrombin, Intriguingly, mAb P11 reacted with beta(2)GP-1 and prothrombin and showed comparable binding affinity to both Ags, with K-d values of 1.6 x 10(-6) M for beta(2)GP-1 vs 3.2 x 10-6 M for prothrombin, This clone may thus define a hitherto unknown shared epitope between beta(2)GP-1 and prothrombin, Sequence analysis of all five clones showed significant mutations of the expressed genes, One rearranged V-D-J segment was repeatedly employed by three clones (mAbs B22, B37, and P13), However, ail three clones used different L chains. Of note, the pairing of VH6-D-J with the L5-Vk1 L chain in mAb P13 resulted in the loss of binding to beta(2)GP-1 and specific reactivity to prothrombin. Together, these data suggest that while the VH6-D-J chain may be important in the binding to beta(2)GP-1, pairing with certain L chains mag influence this binding. These data are the first human IgG anti-P,GP-l and anti-prothrombin sequences reported; both represent the major subsets of antiphospholipid Abs present in antiphospholipid syndrome patients.