Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: ( a ) Percent signal values obtained for a calibrator containing 25 (yellow columns) or 250 ng/mL of E. coli LPS (orange columns) with respect to zero calibrator (red columns) without pre-incubation and with 5-, 10-, 15-, 30- and 60-min pre-incubation of the calibrators with anti- E. coli antibody solution. ( b ) Percent signal values obtained for a calibrator containing 25 (cyan columns) or 250 ng/mL of S. typhimurium LPS (light blue columns) with respect to zero calibrator (blue columns) without pre-incubation and with 5-, 10-, 15-, 30- and 60-min pre-incubation of the calibrators with anti- S. typhimurium antibody solution. Each point is the mean value of three measurements. Error bars correspond to ±SD.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques: Incubation

Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: ( a ) Real-time response obtained for S. typhimurium zero calibrator prepared in assay buffer (arrow 1 to 4) or in bottled water (arrow 7 to end). The arrows indicate the sequence of solutions passing over the chip: assay buffer (start to 1); zero calibrator in assay buffer (arrow 1 to 2); biotinylated anti-species specific antibody (arrow 2 to 3); streptavidin (arrow 3 to 4); 50 mM HCl (arrow 4 to 5); 50 mM NaOH (arrow 5 to 6); assay buffer (arrow 6 to 7); zero calibrator in bottled water (arrow 7 to 8); biotinylated anti-species specific antibody (arrow 8 to 9); streptavidin (arrow 9 to end). ( b ) Real-time response obtained for E. coli zero calibrator prepared in milk. The arrows indicate the sequence of solutions passing over the chip: assay buffer (arrow 1 to 2), zero calibrator prepared in milk (arrow 2 to 3), washing buffer (arrow 3 to 4), assay buffer (arrow 4 to 5), biotinylated anti-species-specific antibody (arrow 5 to 6) and streptavidin (arrow 6 to end). Dashed line corresponds to non-specific binding signal.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques: Sequencing, Binding Assay

Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: Calibration curves obtained for ( a ) E. coli and ( b ) S. typhimurium with calibrators prepared using live untreated (grey squares), heat-treated (blue triangles), ultra-sonicated (red circles) or heat-treated and ultra-sonicated bacteria (green triangles). Each point is the mean value of three measurements. Error bars correspond to ±SD.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques: Sonication, Bacteria

Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: Calibration curves of ( a ) S. typhimurium and ( b ) E. coli . (S x /S 0 ) × 100 represents the percent ratio of each calibrator signal (S x ) to the zero calibrator signal (S 0 ). Each point is the mean value of three chips ±SD.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques:

Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: ( a ) Calibration curves for S. typhimurium (black squares), E. coli O157:H7 (red circles), E. coli top10 (blue triangles) and S . Thomson (green hexagones) obtained from MZIs spotted with S. typhimurium LPS. ( b ) Calibration curves for E. coli O157:H7 (black squares), E. coli top10 (red circles), S. typhimurium (blue triangles) and S. Thomson (green hexagones) obtained from MZIs spotted with E. coli LPS. The dashed vertical lines indicate the bacteria concentration that corresponds to a 50% signal drop with respect to zero calibrator (horizontal black line). Each point is the mean value of seven waveguides per chip ± SD.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques: Bacteria, Concentration Assay

Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: Real-time immunosensor responses when running a zero calibrator over the chip prepared in 10% milk in peptone water (purple line) and a milk sample initially containing 1 cfu of E. coli /25 g milk (pink line) after 7.5 h pre-enrichment. The arrows indicate the sequence of solutions passing over the chip: assay buffer (arrow 1 to 2), zero calibrator/sample in 10% milk in peptone water (arrow 2 to 3), washing (arrow 3 to 4), assay buffer (arrow 4 to 5), biotinylated anti-species-specific antibody (arrow 5 to 6) and streptavidin (arrow 6 to end). Dashed line corresponds to non-specific binding signal.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques: Sequencing, Binding Assay

Journal: Biosensors

Article Title: Simultaneous Detection of Salmonella typhimurium and Escherichia coli O157:H7 in Drinking Water and Milk with Mach–Zehnder Interferometers Monolithically Integrated on Silicon Chips

doi: 10.3390/bios12070507

Figure Lengend Snippet: Comparison of the proposed MZI immunosensor with other optical label-free immunosensors.

Article Snippet: Salmonella enterica serovar typhimurium ( S. typhimurium , ATCC 14028), Escherichia coli O157:H7 ( E. coli O157:H7 , NCTC 12900), Escherichia coli ( TOP10 Competent cells clone 2 , ATCC PTA-5689), and Salmonella enterica serovar Thomson were kindly provided from Delta Foods S.A. (Athens, Greece).

Techniques: Comparison, Bacteria, Immunomagnetic Separation, Imaging

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Metabolic engineering for the production of acetoin and 2,3-butanediol at elevated temperature in Parageobacillus thermoglucosidasius NCIMB 11955

doi: 10.3389/fbioe.2023.1191079

Figure Lengend Snippet: List of strains used in this study.

Article Snippet: Chemically competent E. coli Top10 cells produced in-house were used to propagate the constructed plasmids and plasmids were harvested using Monarch ® Plasmid Miniprep Kit (New England BioLabs).

Techniques:

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Metabolic engineering for the production of acetoin and 2,3-butanediol at elevated temperature in Parageobacillus thermoglucosidasius NCIMB 11955

doi: 10.3389/fbioe.2023.1191079

Figure Lengend Snippet: Assembly of enzyme variants in the acetoin/2,3-BDO pathway and assay of acetolactate decarboxylase activities. (A) Gene configuration of the constructed acetoin/2,3-BDO pathway. The ALS gene is expressed from the G. stereothermophilus lactate dehydrogenase promoter (P ldh ) with the native RBS, the ALD gene is expressed via PT glyceraldehyde 3-phosphate dehydrogenase promoter and RBS9 (TAG​ATA​AAG​GAG​GTA​GAA​CT, taken from the RBS of the locus tag CLB_1812 of Clostridium botulinum ATCC 3502, accession no. CP000726) while the BDH gene is expressed from the native rplS promoter and G. stereothermophilus pheB RBS. T1T2 and TyrS are transcriptional terminators from the E. coli rrnB and B. subtil is tyrS genes, respectively. (B) Assay of α-acetolactate decarboxylases expressed in PT. Y-axis represents unit per mg of protein in the crude cell lysate. Error bars represent standard deviation, n = 3.

Article Snippet: Chemically competent E. coli Top10 cells produced in-house were used to propagate the constructed plasmids and plasmids were harvested using Monarch ® Plasmid Miniprep Kit (New England BioLabs).

Techniques: Construct, Standard Deviation