School of Engineering and Science - Jacobs University

Results
colony PCR with cells of Sinorhizobium meliloti and Xanthomonas campestris.
Both strains are known to contain similar siderophore synthetases but not the
achromobactin biosynthetic gene cluster. While no PCR product was obtained
for S. meliloti, a PCR fragment significantly smaller than the expected product
was detected in X. campestris. A colony PCR of PsmDC3000 served as a
negative control for each PCR mix, while cells of Pss22d and D. chrysanthemi
serve as positive control. Figure 25 gives an example for a screening gel. In
addition, the production of the achromobactin-like siderophore was investigated
by IEF analysis, as already shown in Figure 21. Table 11 summarizes the
preliminary results of both screening methods. So far, the presence of the
achromobactin-like siderophore could be demonstrated for 19 different
pathovars of P. syringae, indicating that the biosynthesis of the achromobactinlike
siderophore is widespread among different pathovars of P. syringae.
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