Also, the research has clearly demonstrated that one of the selected isolates (LS-100) is highly consistent and potent in the transformation of DON and transformation of other selleck chemical trichothecene mycotoxins [20]. It is worth pointing out that isolate SS-3 was selected from the small intestine. Considering that this isolate may offer an advantage in colonizing the small intestine, a region with high physiological significance for animal nutrition, more studies are warranted. In summary, the isolation of pure cultures of DON-transforming bacteria has provided a good NSC23766 price opportunity
for biotransformation research and applications including physiology underlying the transformation and development of microbial FAK inhibitor or enzyme products for field application. The sequence data of partial 16S rRNA genes indicate that the 10 selected isolates with DON-transforming activity belong to four bacterial groups. This diversity may give the host an advantage to ensure the consistency of DON-transformation in the chicken intestine [5, 12, 14]. Despite taxonomic distance between the isolates, they share similar DON transformation function. During the in vitro selection with DON as the sole carbon source in the mineral medium (AIM), DON-transforming bacteria were unable to utilize DON as a source of carbon and energy, and therefore there was no effect of enrichment. However, the desired
bacteria were enriched when the nutritional requirement was met, evidenced by both in vivo and in vitro enrichment. This suggests that DON-transforming bacteria may have an advantage in competition in the intestinal environment when DON is present. Furthermore, all the isolates demonstrated the same function of transforming DON to DOM-1 by deepoxidation. Isolates
SS-3 Ribonucleotide reductase and LS-100 have been further studied and shown to degrade other trichothecene mycotoxins by deepoxidation and/or deacetylation [20]. The results are in agreement with the report by Fuchs et al. [19], in which pure cultures of Eutacterium sp. isolated from the rumen have been studied. It is unclear at present if all the isolates have an identical enzyme or isoenzymes for their DON-transforming activity. Purification and characterization of the enzyme(s) and cloning of the genes encoding the enzymes will lead to a clarification. Conclusions The use of PCR-DGGE guided microbial selection in this study has significantly increased the efficiency for isolating DON-transforming bacteria. The obtained bacterial isolates were able to detoxify DON, which allows further studies for both basic research and application in biotransformation of this mycotoxin. Methods Culture media L10 broth [21] amended with 10% rumen fluid was used for culturing chicken intestinal microbiota and L10 agar was used for plating and colony screening.