Journal: Journal of Biomolecular Techniques : JBT

Article Title: Development of a Membrane-Based Method for Isolation of Genomic DNA from Human Blood

doi: 10.7171/jbt.18-2902-001

Figure Lengend Snippet: Flow chart depicting steps to assemble the filtration units and the methodology to be followed for isolating gDNA using the PES membrane. Note that the methodology described requires no centrifugation steps. RT, room temperature; TE, Tris-EDTA.

Article Snippet: Estimation of the gDNA yield DNA concentrations of different samples were estimated using NanoDrop 2000 (Thermo Fisher Scientific, Waltham, MA, USA).

Techniques: Filtration, Membrane, Centrifugation

Journal: Journal of Biomolecular Techniques : JBT

Article Title: Development of a Membrane-Based Method for Isolation of Genomic DNA from Human Blood

doi: 10.7171/jbt.18-2902-001

Figure Lengend Snippet: Agarose gel electrophoresis of gDNA samples prepared using different PES membranes or the QIAamp commercial kit. A) Buffy coat from the same blood sample was equally distributed and processed for gDNA extraction using either 0.22 µm PES membrane from EMD Millipore (lane 1) or QIAamp DNA Blood Mini Kit from Qiagen (lane 2). B) Buffy coat from different samples was lysed independently, pooled together, and equally distributed and processed for gDNA extraction using 0.22 µm PES membrane from different suppliers (lane 1: EMD Millipore; lane 2: Pall; and lane 3: Sterlitech). C) Buffy coat from the same sample was equally distributed and processed for gDNA extraction using either 0.22 µm (lane 1) or 0.45 µm (lane 2) PES membrane from EMD Millipore. M, DNA MW marker (75 bp–20 kb). Representative of a minimum of 4 independent experiments.

Article Snippet: Estimation of the gDNA yield DNA concentrations of different samples were estimated using NanoDrop 2000 (Thermo Fisher Scientific, Waltham, MA, USA).

Techniques: Agarose Gel Electrophoresis, Extraction, Membrane, Marker

Journal: Journal of Biomolecular Techniques : JBT

Article Title: Development of a Membrane-Based Method for Isolation of Genomic DNA from Human Blood

doi: 10.7171/jbt.18-2902-001

Figure Lengend Snippet: PCR of different HLA targets using gDNA prepared using the PES membrane or QIAamp kit. Buffy coat from the same blood sample was equally distributed and processed for gDNA extraction using either 0.22 µm PES membrane from EMD Millipore (A) or QIAamp DNA Blood Mini Kit from Qiagen (B). Different targets of HLA loci were PCR amplified, as described in Validation of the gDNA isolation method using the PES membrane filter. PCR amplicons were analyzed on 2.5% agarose gel electrophoresis. Representative of a minimum of 4 independent experiments. Lanes 1 and 2: HLA-A Exons 2 and 3; lanes 3 and 4: HLA-B Exons 2 and 3; lanes 5 and 6: HLA-C Exons 2 and 3; lanes 7 and 10: HLA-DPB1 Exons 3 and 2, respectively; lanes 8 and 11: HLA-DQB1 Exons 3 and 2, respectively; lanes 9 and 12: HLA-DRB1 Exons 3 and 2, respectively. M, DNA MW marker (250 bp–10 kb).

Article Snippet: Estimation of the gDNA yield DNA concentrations of different samples were estimated using NanoDrop 2000 (Thermo Fisher Scientific, Waltham, MA, USA).

Techniques: Membrane, Extraction, Amplification, Biomarker Discovery, Isolation, Agarose Gel Electrophoresis, Marker

Journal: Journal of Biomolecular Techniques : JBT

Article Title: Development of a Membrane-Based Method for Isolation of Genomic DNA from Human Blood

doi: 10.7171/jbt.18-2902-001

Figure Lengend Snippet: PCR of different HLA targets using gDNA prepared using PES membranes from different suppliers. Buffy coat from different samples was lysed independently, pooled together, and equally distributed and processed for gDNA extraction using the 0.22 µm PES membrane from different suppliers: EMD Millipore (A), Pall (B), and Sterlitech (C). Different targets of HLA loci were PCR amplified, as described in Validation of the gDNA isolation method using the PES membrane filter. PCR amplicons were analyzed on 2.5% agarose gel electrophoresis. Representative of a minimum of 4 independent experiments. Lane 1: HLA-A Exon 2; lane 2: HLA-A Exon 3; lane 3: HLA-B Exon 2; lane 4: HLA-B Exon 3; lane 5: HLA-C Exon 2; lane 6: HLA-C Exon 3; lane 7: HLA-DPB1 Exon 3; lane 8: HLA-DQB1 Exon 3; lane 9: HLA-DRB1 Exon 3; lane 10: HLA-DPB1 Exon 2; lane 11: HLA-DQB1 Exon 2; lane 12: HLA-DRB1 Exon 2. M, DNA MW marker (250 bp–10 kb).

Article Snippet: Estimation of the gDNA yield DNA concentrations of different samples were estimated using NanoDrop 2000 (Thermo Fisher Scientific, Waltham, MA, USA).

Techniques: Extraction, Membrane, Amplification, Biomarker Discovery, Isolation, Agarose Gel Electrophoresis, Marker

Journal: Journal of Biomolecular Techniques : JBT

Article Title: Development of a Membrane-Based Method for Isolation of Genomic DNA from Human Blood

doi: 10.7171/jbt.18-2902-001

Figure Lengend Snippet: PCR of different HLA targets using gDNA prepared by PES membranes with different pore sizes. Buffy coat from the same sample was equally distributed and processed for gDNA extraction using either 0.22 µm (A) or 0.45 µm (B) PES membrane from EMD Millipore. Different targets of HLA loci were PCR amplified, as described in Validation of the gDNA isolation method using the PES membrane filter. PCR amplicons were analyzed on 2.5% agarose gel electrophoresis. Representative of a minimum of 4 independent experiments. Lanes 1–6: HLA-A Exon 2, HLA-A Exon 3, HLA-B Exon 2, HLA-B Exon 3, HLA-C Exon 2, and HLA-C Exon 3; lanes 7–9: Exon 3 genes of HLA-DPB1, DQB1, and DRB1; lanes 10–12: Exon 2 genes of DPB1, DQB1, and DRB1. M, DNA MW marker (250 bp–10 kb).

Article Snippet: Estimation of the gDNA yield DNA concentrations of different samples were estimated using NanoDrop 2000 (Thermo Fisher Scientific, Waltham, MA, USA).

Techniques: Extraction, Membrane, Amplification, Biomarker Discovery, Isolation, Agarose Gel Electrophoresis, Marker

Journal: Journal of Biomolecular Techniques : JBT

Article Title: Development of a Membrane-Based Method for Isolation of Genomic DNA from Human Blood

doi: 10.7171/jbt.18-2902-001

Figure Lengend Snippet: Agarose gel electrophoresis of gDNA samples digested with either HindIII or EcoRI. DNAs digested with HindIII (A–C); EcoR1 digested gDNAs (D–F). A, D) Buffy coat from the same sample was equally distributed and processed for gDNA extraction using either 0.22 µm PES membrane from EMD Millipore (lane 1) or QIAamp DNA Blood Mini Kit from Qiagen (lane 2). B, E) Buffy coat from 2 different samples was lysed independently, pooled together, and equally distributed and processed for gDNA extraction using the 0.22 µm PES membrane from different suppliers (lane 1: EMD Millipore; lane 2: Pall; lane 3: Sterlitech). C, F) Buffy coat from the same sample was equally distributed and processed for gDNA extraction using either the 0.22 µm (lane 1) or 0.45 µm (lane 2) PES membrane from EMD Millipore. M, DNA MW marker (75 bp–20 kb).

Article Snippet: Estimation of the gDNA yield DNA concentrations of different samples were estimated using NanoDrop 2000 (Thermo Fisher Scientific, Waltham, MA, USA).

Techniques: Agarose Gel Electrophoresis, Extraction, Membrane, Marker

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Numbers of coliform bacteria and phages infecting different strains of E. coli in the sewage samples studied

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Bacteria

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: (A) Southern blot analysis of the agarose gel of first-round PCR products hybridized with the Stx 2-radiolabeled probe (35). (B) Agarose gel electrophoresis and ethidium bromide staining of nested PCR products, with the first-round PCR products as templates. Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 (23); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA HaeIII digest.

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Southern Blot, Agarose Gel Electrophoresis, Staining, Nested PCR, Purification, Molecular Weight, Marker

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Levels of bacteriophages carrying the Stx 2 gene and infecting E. coli O157:H7 in sewage

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques:

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: (A) Western blot (with anti-Stx 2 A subunit) of crude concentrated supernatants of cultures of E. coli O157:H7 ATCC 43888 infected with: 10, 1, and 0.1 ml of sewage that had been centrifuged, filtered, and DNase treated (lanes 2, 3, and 4, respectively); sonically derived lysates of E. coli O157:H7 ATCC 43889 (lane 1) and ATCC 43888 (lane 5); sewage that had been centrifuged, filtered, and DNase treated (lane 6); and prestained protein size standards in kDa (lane M). (B) Lanes are as in panel A, after cutting a strip of the SDS-PAGE slab gel of the zone to which the A subunit migrates, eluting the strips electrophoretically, and concentrating the eluates by passage through 10K cutoff filtration membrane microconcentrators (Microsep) by centrifugation at 16,000 × g at 4°C.

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Western Blot, Infection, Derivative Assay, Stripping Membranes, SDS Page, Filtration, Membrane, Centrifugation

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Visual estimation of Vero cell cytotoxicity. Wells 1 to 5 were inoculated with growth medium; well 6 was inoculated with sewage that had been centrifuged, filtered, and DNase treated; wells 7, 8, 9, and 10 were inoculated with 10-fold dilutions of a crude supernatant of E. coli O157:H7 ATCC 43888 infected with 10 ml of sewage that had been centrifuged, filtered, and DNase treated. Wells 11, 12, 13, 14, and 15 were like wells 6, 7, 8, 9, and 10, respectively, but with the addition of anti-Stx 2 subunit A MAb 11E10.

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Infection

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Numbers of coliform bacteria and phages infecting different strains of E. coli in the sewage samples studied

Article Snippet: E. coli O157:H7 ATCC 43888, which does not produce either Shiga toxin 1 or 2 and does not possess the genes for these toxins, was used as a negative control in all experiments.

Techniques:

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: (A) Southern blot analysis of the agarose gel of first-round PCR products hybridized with the Stx 2-radiolabeled probe (35). (B) Agarose gel electrophoresis and ethidium bromide staining of nested PCR products, with the first-round PCR products as templates. Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 (23); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA HaeIII digest.

Article Snippet: E. coli O157:H7 ATCC 43888, which does not produce either Shiga toxin 1 or 2 and does not possess the genes for these toxins, was used as a negative control in all experiments.

Techniques: Southern Blot, Agarose Gel Electrophoresis, Staining, Nested PCR, Purification, Molecular Weight, Marker

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Levels of bacteriophages carrying the Stx 2 gene and infecting E. coli O157:H7 in sewage

Article Snippet: E. coli O157:H7 ATCC 43888, which does not produce either Shiga toxin 1 or 2 and does not possess the genes for these toxins, was used as a negative control in all experiments.

Techniques:

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: (A) Western blot (with anti-Stx 2 A subunit) of crude concentrated supernatants of cultures of E. coli O157:H7 ATCC 43888 infected with: 10, 1, and 0.1 ml of sewage that had been centrifuged, filtered, and DNase treated (lanes 2, 3, and 4, respectively); sonically derived lysates of E. coli O157:H7 ATCC 43889 (lane 1) and ATCC 43888 (lane 5); sewage that had been centrifuged, filtered, and DNase treated (lane 6); and prestained protein size standards in kDa (lane M). (B) Lanes are as in panel A, after cutting a strip of the SDS-PAGE slab gel of the zone to which the A subunit migrates, eluting the strips electrophoretically, and concentrating the eluates by passage through 10K cutoff filtration membrane microconcentrators (Microsep) by centrifugation at 16,000 × g at 4°C.

Article Snippet: E. coli O157:H7 ATCC 43888, which does not produce either Shiga toxin 1 or 2 and does not possess the genes for these toxins, was used as a negative control in all experiments.

Techniques: Western Blot, Infection, Derivative Assay, Stripping Membranes, SDS Page, Filtration, Centrifugation

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Visual estimation of Vero cell cytotoxicity. Wells 1 to 5 were inoculated with growth medium; well 6 was inoculated with sewage that had been centrifuged, filtered, and DNase treated; wells 7, 8, 9, and 10 were inoculated with 10-fold dilutions of a crude supernatant of E. coli O157:H7 ATCC 43888 infected with 10 ml of sewage that had been centrifuged, filtered, and DNase treated. Wells 11, 12, 13, 14, and 15 were like wells 6, 7, 8, 9, and 10, respectively, but with the addition of anti-Stx 2 subunit A MAb 11E10.

Article Snippet: E. coli O157:H7 ATCC 43888, which does not produce either Shiga toxin 1 or 2 and does not possess the genes for these toxins, was used as a negative control in all experiments.

Techniques: Infection

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Numbers of coliform bacteria and phages infecting different strains of E. coli in the sewage samples studied

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques:

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: (A) Southern blot analysis of the agarose gel of first-round PCR products hybridized with the Stx 2-radiolabeled probe (35). (B) Agarose gel electrophoresis and ethidium bromide staining of nested PCR products, with the first-round PCR products as templates. Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 (23); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA HaeIII digest.

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Southern Blot, Agarose Gel Electrophoresis, Staining, Nested PCR, Purification, Molecular Weight, Marker

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Levels of bacteriophages carrying the Stx 2 gene and infecting E. coli O157:H7 in sewage

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques:

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: (A) Western blot (with anti-Stx 2 A subunit) of crude concentrated supernatants of cultures of E. coli O157:H7 ATCC 43888 infected with: 10, 1, and 0.1 ml of sewage that had been centrifuged, filtered, and DNase treated (lanes 2, 3, and 4, respectively); sonically derived lysates of E. coli O157:H7 ATCC 43889 (lane 1) and ATCC 43888 (lane 5); sewage that had been centrifuged, filtered, and DNase treated (lane 6); and prestained protein size standards in kDa (lane M). (B) Lanes are as in panel A, after cutting a strip of the SDS-PAGE slab gel of the zone to which the A subunit migrates, eluting the strips electrophoretically, and concentrating the eluates by passage through 10K cutoff filtration membrane microconcentrators (Microsep) by centrifugation at 16,000 × g at 4°C.

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Western Blot, Infection, Derivative Assay, Stripping Membranes, SDS Page, Filtration, Centrifugation

Journal:

Article Title: Abundance in Sewage of Bacteriophages That Infect Escherichia coli O157:H7 and That Carry the Shiga Toxin 2 Gene

doi:

Figure Lengend Snippet: Visual estimation of Vero cell cytotoxicity. Wells 1 to 5 were inoculated with growth medium; well 6 was inoculated with sewage that had been centrifuged, filtered, and DNase treated; wells 7, 8, 9, and 10 were inoculated with 10-fold dilutions of a crude supernatant of E. coli O157:H7 ATCC 43888 infected with 10 ml of sewage that had been centrifuged, filtered, and DNase treated. Wells 11, 12, 13, 14, and 15 were like wells 6, 7, 8, 9, and 10, respectively, but with the addition of anti-Stx 2 subunit A MAb 11E10.

Article Snippet: Lanes: 1, DNA from E. coli ATCC 43889, which bears Stx 2; 2, DNA from bacteriophage 933W, which bears Stx 2 ( 23 ); 4, 8, and 12, DNA of bacteriophages purified from 10 ml of sewage; 5, 9, and 13, DNA of bacteriophages purified from 1 ml of sewage water; 3, 6, and 10, DNA from E. coli ATCC 43888, which does not bear Stx 2; 7, 11, and 14, negative controls containing no template; M, molecular weight marker, φX-174-RF DNA Hae III digest.

Techniques: Infection