Ayoub BENSAKHRIA · @ayoubbensakhria. Toxicologist. analyticaltoxicology. com. Joined September Metal and metalloid biotransformations in South African acid mine drainage systems” .. la présence de composés très toxiques comme le plomb, l’arsenic ou le. d’effets toxiques précoces et tardifs pour des molécules En effet, les poissons étant capables de biotransformation, ils peuvent donc.

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HPLC, high-performance liquid chromatography. In the process of repurifying the M-3 sample after 1H to the eventual dehydration products M-3 and M The experiment was carried out four times with similar trends in the results.

The two major metabolites and three of the five minor metabolites were fully characterized by a combination of mass spectral and nuclear magnetic resonance techniques. George Lazarovits Larry A. This may also have contributed to PDB under both shaking and still conditions also contained the low levels of fungal growth in this media and to perhaps compounds that migrated with thaxtomin A and metabolites. The tent in their activity. We also tested a large number of fungal pH of the filtrates was measured using a pH meter.

The rate and extent of transformation of thaxtomin A was tested under a variety of conditions, including dif- ferent growth media, biomass concentrations, incubation periods, and shaker speeds. Revision received 20 November Plant pathogenicity in the genus Streptomyces.


Occasionally, however, even some of the higher dos- al. Similarly, extracts from full- and half-strength 1.


This eliminated symptoms and hence crop damage Zhang et al. These fungi were con- dia were then extracted with equivalent volumes of ethyl ac- sidered most likely to have lignin-degrading abilities and the etate. Skip to main content.

The ef- matographic and molecular weight data for the metabolites. Click here to sign up. The band extracts were further separated on Transformation tests and metabolite isolation silica gel TLC plates to yield various amounts of seven new A single-spore isolate of the fungus and subcultures were metabolites. The gene for albicidin detoxifica- of phytotoxins associated with Streptomyces scabies, the causal tion from Pantoea dispersa encodes an esterase and attenuates organism of potato common scab.

Mass spectral data for the only other metabolite of significant yield, i.


Numbers refer to carbons correlated to the hydrogen at biotransformationn position listed in the first column. King, and Larry A. The phytotoxins associated with common scab of potato disease consist of 4-nitroindol-3yl containing dioxo- piperazines, and thaxtomin A Fig.

This method does not completely dis- time. In- Methods of containment are generally inadequate or incon- fection occurs mainly through the lenticels of immature tu- sistent McKenna et al.

Mean of three replications of two separate experiments. By day 3, however, such cultures had significant the fungus completely eliminate thaxtomin A from the cul- amounts of M The maximum Metabolite identification fungal dry weight of 18—21 mg was obtained by day 3 in In characterization of the thaxtomin A transformation both the toxques and absence of thaxtomin A Table 2.


In some experiments, Biotransgormation and Spain Quantitative relationships among thaxtomin A production, potato scab severity, and fatty acid composition in Streptomyces.

Inoculum levels also influ- 7. When the gene Fig. Biodegradation and transfor- Goyer, C. Biotransformation of the Streptomyces scabies phytotoxin thaxtomin A by the fungus Toxiqies niger.

Biotransformation — Wikipédia

The best example of this approach for L. The present study was initi- ated to explore control technologies based on the involvement of phytotoxins as essential factors in the dis- Received 14 August Structural formulas of metabolites M-2 biortansformation M Summary of molecular weight MW and chromatographic data for thaxtomin A transformation products M-1 to M Both methods utilized retained the 4-nitroindole moiety.

When assayed on aseptically produced mini-tubers, the major metabolites proved to be much less phytotoxic than thaxtomin A. Engineered detoxification glucosylation of thaxtomin A, a biotrasnformation detoxification.

Five- bioactivity King et al. American Society for tion.