Volume 7, Number 3—June 2001
Dispatch
Expanding Drug Resistance through Integron Acquisition by IncFI Plasmids of Salmonella enterica Typhimurium
Figure 2
![Figure 2. . Restriction enzyme analysis and detection of common genetic elements in IncFI plasmids. Numbers above each lane indicate plasmid reference numbers as defined (Table). M and M' are HindIII-digested lambda DNA and 1-kb Plus DNA ladder (GibcoBRL), respectively. A: agarose (0.8%) gel electrophoresis in 1x Tris-borate-EDTA buffer of plasmids digested with restriction endonucleases SalI and SphI. DNA was stained with ethidium bromide and visualized under UV light. B: Southern blot hybridization of SalI-digested plasmids with the IS1936-Kmr probe purified as 1.8-kb SalI fragment from plasmid pACYC184::Tn1935 (10). C and D: Southern blot hybridizations of SphI-digested plasmids with the tnpM and merA probes, respectively. The tnpM probe was amplified with primers corresponding to nt 3689-3709 and nt 4070-4050 of the released Tn21 sequence (GenEMBL accession no. AF071413). For synthesis of the merA probe, primers annealing to nt 17224-17249 and nt 17931-17907 of the Tn21 sequence were used. Plasmid pACYC184::Tn21 (10) was used as the template. Probes were labeled with [α-32P]dCTP by using a random priming kit (GibcoBRL, Rockville, MD). The arrows point to predicted hybridization fragments. Restriction enzyme analysis and detection of common genetic elements in IncFI plasmids. Numbers above each lane indicate plasmid reference numbers as defined (Table). M and M' are HindIII-digested lambda DNA and 1-kb Plus DNA ladder (GibcoBRL), respectively. A: agarose (0.8%) gel electrophoresis in 1x Tris-borate-EDTA buffer of plasmids digested with restriction endonucleases SalI and SphI. DNA was stained with ethidium bromide and visualized under UV light. B: Southern blot hybridization of Sal](/eid/images/01-7314-F2.jpg)
Figure 2. . Restriction enzyme analysis and detection of common genetic elements in IncFI plasmids. Numbers above each lane indicate plasmid reference numbers as defined (Table). M and M' are HindIII-digested lambda DNA and 1-kb Plus DNA ladder (GibcoBRL), respectively. A: agarose (0.8%) gel electrophoresis in 1x Tris-borate-EDTA buffer of plasmids digested with restriction endonucleases SalI and SphI. DNA was stained with ethidium bromide and visualized under UV light. B: Southern blot hybridization of SalI-digested plasmids with the IS1936-Kmr probe purified as 1.8-kb SalI fragment from plasmid pACYC184::Tn1935 (10). C and D: Southern blot hybridizations of SphI-digested plasmids with the tnpM and merA probes, respectively. The tnpM probe was amplified with primers corresponding to nt 3689-3709 and nt 4070-4050 of the released Tn21 sequence (GenEMBL accession no. AF071413). For synthesis of the merA probe, primers annealing to nt 17224-17249 and nt 17931-17907 of the Tn21 sequence were used. Plasmid pACYC184::Tn21 (10) was used as the template. Probes were labeled with [α-32P]dCTP by using a random priming kit (GibcoBRL, Rockville, MD). The arrows point to predicted hybridization fragments.
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