Novobiocin analysis

Gmuender, H., Kuratli, K., Di Padova, K., Gray, C. P., Keck, W., and Evers, S. (2001). Gene expression changes triggered by exposure of Haemophilus influenzae to novobiocin or ciprofloxacin combined transcription and translation analysis. Genome Res. 11, 28-42. 

Gmuender H et al. Gene expression changes triggered by exposure of Haemophilus influenzae to novobiocin or cipro-flaxin combined transcription and translation analysis. Genome Res 2001 11 28-42. 

Novobiocin (NBC) is used for the treatment of mastitis in dairy cattle. In 1982, the tolerance level was set at 100 pg/kg in milk from dairy animals. An HPLC assay was developed for NBC determination in bovine milk at a tolerance level (214). The milk sample was diluted with buffer, the proteins were precipitated with MeOH, and the solution was filtered. The filtrate was injected directly into an HPLC system with UV detection. The interlaboratory study was realized for the analysis of two concentrations of NBC in fortified control milk samples. Recoveries of NBC reported by the participating laboratories were 89-99% at 50 pg/kg, 93-101% at 100 pg/kg, and 89-100% at 2 mg/kg. The CVs ranged from 2.0% to 6.2%. All laboratories described the procedure as rapid and simple, allowing the preparation of 20 samples in less than 2 hours. 

K. Tsuji and J. H. Robertson, High-performance liquid chroma-togrpahic analysis of novobiocin, J. Chromatogr., 94 245 (1974). 

More robust composites are made with conducting solid matrices such as carbon-doped epoxies or sol-gels. Leech et al. [24] doped a polishable graphite-epoxy composite with RUO2 to yield an electtode at which saccharide-based antibiotics (e.g streptomycin and novobiocin) were oxidized. Typical flow-injection analysis data (0.5 M NaOH carrier solution) with amperometric detection at 0.4 V vs. Ag/AgCl are summarized in Table 1. 

The ability of washed cells of S. niveus (BC-345) to produce novobiocin in a glucose-phosphate medium has been reported previously (Owen, 1963). Experiments in this laboratory were performed to determine if the formation of a particular segment of the novobiocin molecule was limiting the rate of its synthesis as a whole. This was accomplished by adding various compounds to a washed cell system and determining the effect of these compounds on the rate of novobiocin synthesis. The results are illustrated in Fig. 4. Addition of the A and B rings of novobiocin to the indicated system resulted in an apparent increase in the rate of novobiocin synthesis by UV analysis. Upon paper chromatographic... 

Addition of the B ring and 4-hy(h oxybenzoic acid again resulted in an increase by UV assay and in this case papergram analysis showed that all the material produced was novobiocin. The addition of 4-hydroxybenzoic acid alone or novobiocic acid had no effect on the rate of novobiocin synthesis. 

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