nitrocefin Search Results


  • Logo
  • About
  • News
  • Press Release
  • Team
  • Advisors
  • Partners
  • Contact
  • Bioz Stars
  • Bioz vStars
  • 93
    Thermo Fisher oxoid nitrocefin powder
    Oxoid Nitrocefin Powder, supplied by Thermo Fisher, used in various techniques. Bioz Stars score: 93/100, based on 5 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/oxoid nitrocefin powder/product/Thermo Fisher
    Average 93 stars, based on 5 article reviews
    Price from $9.99 to $1999.99
    oxoid nitrocefin powder - by Bioz Stars, 2020-08
    93/100 stars
      Buy from Supplier

    94
    Millipore cefinase plus
    Cefinase Plus, supplied by Millipore, used in various techniques. Bioz Stars score: 94/100, based on 3 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/cefinase plus/product/Millipore
    Average 94 stars, based on 3 article reviews
    Price from $9.99 to $1999.99
    cefinase plus - by Bioz Stars, 2020-08
    94/100 stars
      Buy from Supplier

    85
    Becton Dickinson bbl cefinase nitrocefin disks
    Distribution of resistance phenotypes among Haemophilus parainfluenzae isolates. CLSI Clinical and Laboratory Standards Institute, EUCAST European Committee on Antimicrobial Susceptibility Testing, BLNAS beta-lactamase-negative, <t>cefinase-negative</t> susceptible to ampicillin, BLNAI beta-lactamase-negative, cefinase-negative, ampicillin intermediate, low-BLNAR beta-lactamase-negative, cefinase-negative, ampicillin resistant (MIC Am = 0.5–2.0 mg/L), BLNAR beta-lactamase-negative, cefinase-negative, ampicillin resistant (MIC Am ≥ 2.0 mg/L), BLPAS beta-lactamase-positive, cefinase-negative, ampicillin and/or amoxicillin susceptible, BLPAI beta-lactamase-positive, cefinase-negative, ampicillin intermediate, BLPAR beta-lactamase-positive, cefinase-negative, ampicillin and bezylpenicillin resistant, amoxicillin-clavulanate susceptible, BLPACR beta-lactamase-positive, cefinase-negative, ampicillin, amoxicillin-clavulanate or benzylpenicillin resistant, BLPBR beta-lactamase-positive, cefinase-positive, resistant to one or more beta-lactams (benzylpenicillin, ampicillin, cephalosporins or carbapenems).
    Bbl Cefinase Nitrocefin Disks, supplied by Becton Dickinson, used in various techniques. Bioz Stars score: 85/100, based on 7 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/bbl cefinase nitrocefin disks/product/Becton Dickinson
    Average 85 stars, based on 7 article reviews
    Price from $9.99 to $1999.99
    bbl cefinase nitrocefin disks - by Bioz Stars, 2020-08
    85/100 stars
      Buy from Supplier

    85
    Becton Dickinson bbl cefinase nitrocefin disk
    Detection of β -lactamase associated with outer membrane vesicles (OMVs) using <t>nitrocefin</t> disk. (1) Penicillin-sensitive Pm 12948 strain; (2) OMVs; and (3) penicillin-resistant Pm 12945 cells.
    Bbl Cefinase Nitrocefin Disk, supplied by Becton Dickinson, used in various techniques. Bioz Stars score: 85/100, based on 8 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/bbl cefinase nitrocefin disk/product/Becton Dickinson
    Average 85 stars, based on 8 article reviews
    Price from $9.99 to $1999.99
    bbl cefinase nitrocefin disk - by Bioz Stars, 2020-08
    85/100 stars
      Buy from Supplier

    93
    Abcam nitrocefin
    Contribution of efflux pumps and β-lactamase to AMR induced by indole. (A) The effects of PAβN on Amp resistance induced by indole. PAβN (5 μg/ml was added to the agar plate. (B) Expression of the ampC gene and β-lactamase activity in the presence of indole and Amp during growth. Total RNA was isolated from cultures after 36 h of incubation with 50 or 75 μg/ml Amp or 1 mM indole or both of these. Exponentially growing cells were treated with Amp or indole for 3 h. Following incubation, β-lactamase activity was measured. Enzyme activity was measured in nmol min -1 mg -1 <t>nitrocefin</t> hydrolyzed. (C) Amp susceptibility test in P. putida ΔampC and P. aeruginosa ΔampC (PA4110). Exponentially growing cells were serially diluted, and each dilution of the solution was spotted on plates and incubated for 24 h. (D) Amp susceptibility test in P. aeruginosa ΔoprM (PA0427) and ΔmexB (PA0426) and P. aeruginosa MPAO1.
    Nitrocefin, supplied by Abcam, used in various techniques. Bioz Stars score: 93/100, based on 13 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Abcam
    Average 93 stars, based on 13 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    93/100 stars
      Buy from Supplier

    88
    Becton Dickinson nitrocefin discs
    Contribution of efflux pumps and β-lactamase to AMR induced by indole. (A) The effects of PAβN on Amp resistance induced by indole. PAβN (5 μg/ml was added to the agar plate. (B) Expression of the ampC gene and β-lactamase activity in the presence of indole and Amp during growth. Total RNA was isolated from cultures after 36 h of incubation with 50 or 75 μg/ml Amp or 1 mM indole or both of these. Exponentially growing cells were treated with Amp or indole for 3 h. Following incubation, β-lactamase activity was measured. Enzyme activity was measured in nmol min -1 mg -1 <t>nitrocefin</t> hydrolyzed. (C) Amp susceptibility test in P. putida ΔampC and P. aeruginosa ΔampC (PA4110). Exponentially growing cells were serially diluted, and each dilution of the solution was spotted on plates and incubated for 24 h. (D) Amp susceptibility test in P. aeruginosa ΔoprM (PA0427) and ΔmexB (PA0426) and P. aeruginosa MPAO1.
    Nitrocefin Discs, supplied by Becton Dickinson, used in various techniques. Bioz Stars score: 88/100, based on 10 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin discs/product/Becton Dickinson
    Average 88 stars, based on 10 article reviews
    Price from $9.99 to $1999.99
    nitrocefin discs - by Bioz Stars, 2020-08
    88/100 stars
      Buy from Supplier

    88
    bioMerieux nitrocefin test
    Contribution of efflux pumps and β-lactamase to AMR induced by indole. (A) The effects of PAβN on Amp resistance induced by indole. PAβN (5 μg/ml was added to the agar plate. (B) Expression of the ampC gene and β-lactamase activity in the presence of indole and Amp during growth. Total RNA was isolated from cultures after 36 h of incubation with 50 or 75 μg/ml Amp or 1 mM indole or both of these. Exponentially growing cells were treated with Amp or indole for 3 h. Following incubation, β-lactamase activity was measured. Enzyme activity was measured in nmol min -1 mg -1 <t>nitrocefin</t> hydrolyzed. (C) Amp susceptibility test in P. putida ΔampC and P. aeruginosa ΔampC (PA4110). Exponentially growing cells were serially diluted, and each dilution of the solution was spotted on plates and incubated for 24 h. (D) Amp susceptibility test in P. aeruginosa ΔoprM (PA0427) and ΔmexB (PA0426) and P. aeruginosa MPAO1.
    Nitrocefin Test, supplied by bioMerieux, used in various techniques. Bioz Stars score: 88/100, based on 3 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin test/product/bioMerieux
    Average 88 stars, based on 3 article reviews
    Price from $9.99 to $1999.99
    nitrocefin test - by Bioz Stars, 2020-08
    88/100 stars
      Buy from Supplier

    92
    Avantor nitrocefin
    AmpC activity is increased in dacB mutants but not in LT mutants. <t>Nitrocefin</t> hydrolysis activity assays of P. aeruginosa mutants grown under basal conditions (A) and induced conditions (medium supplemented with 50 μg/ml cefoxitin) (B) were conducted.
    Nitrocefin, supplied by Avantor, used in various techniques. Bioz Stars score: 92/100, based on 12 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Avantor
    Average 92 stars, based on 12 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    92/100 stars
      Buy from Supplier

    91
    Cayman Chemical nitrocefin
    (A) Ethidium bromide (EtBr) loading in the wild-type, Δ rsaF a F b , Δ rsaF a F b rsaA , and Δ acrAB2-nodT strains. Fluorescence at 605 nm was monitored for 60 min to detect the amount of EtBr remaining inside the cell. Curves and error bars represent the averages and standard deviations, respectively, from three biological replicates. The <t>nitrocefin</t> hydrolysis assay was performed with samples incubated in (B) PIPES or (C) PIPES with 120 μM polymyxin B nonapeptide (PMXBN) for 360 min at room temperature. Absorbance at 490 nm ( A 490 ) was measured every 3 min to monitor nitrocefin hydrolysis. The average and standard deviation from three biological replicates are plotted. a.u., arbitrary units.
    Nitrocefin, supplied by Cayman Chemical, used in various techniques. Bioz Stars score: 91/100, based on 9 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Cayman Chemical
    Average 91 stars, based on 9 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    91/100 stars
      Buy from Supplier

    92
    Glaxo Smith nitrocefin
    (A) Ethidium bromide (EtBr) loading in the wild-type, Δ rsaF a F b , Δ rsaF a F b rsaA , and Δ acrAB2-nodT strains. Fluorescence at 605 nm was monitored for 60 min to detect the amount of EtBr remaining inside the cell. Curves and error bars represent the averages and standard deviations, respectively, from three biological replicates. The <t>nitrocefin</t> hydrolysis assay was performed with samples incubated in (B) PIPES or (C) PIPES with 120 μM polymyxin B nonapeptide (PMXBN) for 360 min at room temperature. Absorbance at 490 nm ( A 490 ) was measured every 3 min to monitor nitrocefin hydrolysis. The average and standard deviation from three biological replicates are plotted. a.u., arbitrary units.
    Nitrocefin, supplied by Glaxo Smith, used in various techniques. Bioz Stars score: 92/100, based on 36 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Glaxo Smith
    Average 92 stars, based on 36 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    92/100 stars
      Buy from Supplier

    94
    Carbosynth nitrocefin
    Biochemical analysis of relebactam inhibition of M. abscessus β -lactamase, Bla Mab . Our novel Thin Layer Chromatography (TLC) assay (2a) exhibiting the activity of Bla Mab in the turnover of penicillin V (high R f value) to penicilloic acid (lower R f value). In the absence, or termination of activity of Bla Mab (by boiling (100 °C) for 1 h) or addition of known inhibitor avibactam ( Lefebvre et al., 2017 ) (200 μg/mL) no lower R f value spot corresponding to penicilloic acid is seen on the TLC plate. The addition of relebactam to the reaction between Bla Mab and penicillin V also results in the absence of the lower Rf value spot, suggesting inhibition of Bla Mab (2a). This observed inhibition is validated by a spectrophotometric analysis, where the turnover of <t>nitrocefin</t> (100 μM) by Bla Mab (0.25 nM) was monitored at 486 nm with a varying concentration of relebactam (0, 0.1, 1, 10 and 100 μM). The increase in concentration of relebactam resulted in partial inhibition of nitrocefin turnover at 1 μM and total abrogation at 10 μM (2b). The initial velocity (v i ) of the reaction between Bla Mab and nitrocefin was monitored for a range of substrate concentrations (1-500 μM) and relebactam concentrations (0, 0.5, 0.75, 1 and 2.5 μM). This data was plotted v i vs [S] in order to determine K m values (2c/f). The values for K obs were obtained as previously described ( Dubée et al., 2014 ) and plotted against relebactam concentrations ([I]) to deduce a carbamylation rate ( K 2 / K i ) for Bla Mab (2d). The kinetics of Bla Mab decarbamylation were assessed to show the recovery of nitrocefin hydrolysis by Bla Mab after inhibition by relebactam in order to derive a K off value (2e). Kinetic parameters were derived as described previously (2f) ( Dubée et al., 2014 ).
    Nitrocefin, supplied by Carbosynth, used in various techniques. Bioz Stars score: 94/100, based on 3 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Carbosynth
    Average 94 stars, based on 3 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    94/100 stars
      Buy from Supplier

    90
    Merck & Co nitrocefin
    SnoopRing and PilinRing cyclization conferred thermal resilience. ( A ) Cyclization decreased heat-induced aggregation. BLA, Pilin-C-BLA-Isopeptag and SnoopTag-BLA-SnoopCatcher were heated at the indicated temperature for 10 min, centrifuged, and the supernatant analyzed by SDS-PAGE with Coomassie staining. C is control without incubation. ( B ) Plot of heat-induced aggregation, from quantifying SDS-PAGE. ( C ) Cyclization enhanced the catalytic activity following heating. BLA, SnoopTag-BLA-SnoopCatcher, Pilin-C-BLA-Isopeptag and SpyTag-BLA-SpyCatcher were incubated for 10 min at the indicated temperature, before returning to RT and then running a <t>nitrocefin</t> colorimetric activity assay. The initial rates of reaction were calculated using the linear portion of the enzyme curves. Data were normalized using the initial rate of reaction at 25 °C as 100% recovered activity. (All are mean of triplicate ± 1 s.d.; some error bars are too small to be visible.)
    Nitrocefin, supplied by Merck & Co, used in various techniques. Bioz Stars score: 90/100, based on 7 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Merck & Co
    Average 90 stars, based on 7 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    90/100 stars
      Buy from Supplier

    91
    Merck KGaA nitrocefin
    Beta-lactamase production in ceftazidime and tazobactam-piperacillin resistant isolates. Activity was measured using <t>nitrocefin,</t> in a chromogenic assay by calculating the change in A486/390 per minute. The dashed line indicates the value of the negative control (PAO1). Ceftazidime (CAZ); piperacillin/tazobactam (TZP). Bars indicate standard error
    Nitrocefin, supplied by Merck KGaA, used in various techniques. Bioz Stars score: 91/100, based on 4 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Merck KGaA
    Average 91 stars, based on 4 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    91/100 stars
      Buy from Supplier

    92
    ProGenosis nitrocefin
    Beta-lactamase production in ceftazidime and tazobactam-piperacillin resistant isolates. Activity was measured using <t>nitrocefin,</t> in a chromogenic assay by calculating the change in A486/390 per minute. The dashed line indicates the value of the negative control (PAO1). Ceftazidime (CAZ); piperacillin/tazobactam (TZP). Bars indicate standard error
    Nitrocefin, supplied by ProGenosis, used in various techniques. Bioz Stars score: 92/100, based on 3 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/ProGenosis
    Average 92 stars, based on 3 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    92/100 stars
      Buy from Supplier

    93
    Thermo Fisher nitrocefin
    Suppression efficiency of four-base codon/tRNA pairs measured by <t>nitrocefin</t> turnover. See Materials and Methods for definition of units. Readthrough of UAG, AGGA, CCCU, CUAG and UAGA was 0.8–1.7 units, while TOP10 cells alone exhibit about 0.9 unit. Suppression of four-base codons resulted in 17–240 units of activity, compared to 970 for suppression of UAG by supD . Results are the average of three to five independent trials per data point.
    Nitrocefin, supplied by Thermo Fisher, used in various techniques. Bioz Stars score: 93/100, based on 659 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Thermo Fisher
    Average 93 stars, based on 659 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    93/100 stars
      Buy from Supplier

    88
    Millipore nitrocefin discs
    Suppression efficiency of four-base codon/tRNA pairs measured by <t>nitrocefin</t> turnover. See Materials and Methods for definition of units. Readthrough of UAG, AGGA, CCCU, CUAG and UAGA was 0.8–1.7 units, while TOP10 cells alone exhibit about 0.9 unit. Suppression of four-base codons resulted in 17–240 units of activity, compared to 970 for suppression of UAG by supD . Results are the average of three to five independent trials per data point.
    Nitrocefin Discs, supplied by Millipore, used in various techniques. Bioz Stars score: 88/100, based on 8 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin discs/product/Millipore
    Average 88 stars, based on 8 article reviews
    Price from $9.99 to $1999.99
    nitrocefin discs - by Bioz Stars, 2020-08
    88/100 stars
      Buy from Supplier

    92
    Acme Bioscience nitrocefin
    Suppression efficiency of four-base codon/tRNA pairs measured by <t>nitrocefin</t> turnover. See Materials and Methods for definition of units. Readthrough of UAG, AGGA, CCCU, CUAG and UAGA was 0.8–1.7 units, while TOP10 cells alone exhibit about 0.9 unit. Suppression of four-base codons resulted in 17–240 units of activity, compared to 970 for suppression of UAG by supD . Results are the average of three to five independent trials per data point.
    Nitrocefin, supplied by Acme Bioscience, used in various techniques. Bioz Stars score: 92/100, based on 3 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
    https://www.bioz.com/result/nitrocefin/product/Acme Bioscience
    Average 92 stars, based on 3 article reviews
    Price from $9.99 to $1999.99
    nitrocefin - by Bioz Stars, 2020-08
    92/100 stars
      Buy from Supplier

    Image Search Results


    Distribution of resistance phenotypes among Haemophilus parainfluenzae isolates. CLSI Clinical and Laboratory Standards Institute, EUCAST European Committee on Antimicrobial Susceptibility Testing, BLNAS beta-lactamase-negative, cefinase-negative susceptible to ampicillin, BLNAI beta-lactamase-negative, cefinase-negative, ampicillin intermediate, low-BLNAR beta-lactamase-negative, cefinase-negative, ampicillin resistant (MIC Am = 0.5–2.0 mg/L), BLNAR beta-lactamase-negative, cefinase-negative, ampicillin resistant (MIC Am ≥ 2.0 mg/L), BLPAS beta-lactamase-positive, cefinase-negative, ampicillin and/or amoxicillin susceptible, BLPAI beta-lactamase-positive, cefinase-negative, ampicillin intermediate, BLPAR beta-lactamase-positive, cefinase-negative, ampicillin and bezylpenicillin resistant, amoxicillin-clavulanate susceptible, BLPACR beta-lactamase-positive, cefinase-negative, ampicillin, amoxicillin-clavulanate or benzylpenicillin resistant, BLPBR beta-lactamase-positive, cefinase-positive, resistant to one or more beta-lactams (benzylpenicillin, ampicillin, cephalosporins or carbapenems).

    Journal: Scientific Reports

    Article Title: Prevalence of susceptibility patterns of opportunistic bacteria in line with CLSI or EUCAST among Haemophilus parainfluenzae isolated from respiratory microbiota

    doi: 10.1038/s41598-020-68161-5

    Figure Lengend Snippet: Distribution of resistance phenotypes among Haemophilus parainfluenzae isolates. CLSI Clinical and Laboratory Standards Institute, EUCAST European Committee on Antimicrobial Susceptibility Testing, BLNAS beta-lactamase-negative, cefinase-negative susceptible to ampicillin, BLNAI beta-lactamase-negative, cefinase-negative, ampicillin intermediate, low-BLNAR beta-lactamase-negative, cefinase-negative, ampicillin resistant (MIC Am = 0.5–2.0 mg/L), BLNAR beta-lactamase-negative, cefinase-negative, ampicillin resistant (MIC Am ≥ 2.0 mg/L), BLPAS beta-lactamase-positive, cefinase-negative, ampicillin and/or amoxicillin susceptible, BLPAI beta-lactamase-positive, cefinase-negative, ampicillin intermediate, BLPAR beta-lactamase-positive, cefinase-negative, ampicillin and bezylpenicillin resistant, amoxicillin-clavulanate susceptible, BLPACR beta-lactamase-positive, cefinase-negative, ampicillin, amoxicillin-clavulanate or benzylpenicillin resistant, BLPBR beta-lactamase-positive, cefinase-positive, resistant to one or more beta-lactams (benzylpenicillin, ampicillin, cephalosporins or carbapenems).

    Article Snippet: To determine the beta-lactamase production ability, either benzylpenicillin (1 U, Becton Dickinson, Franklin Lakes, USA) or cefinase test (Becton Dickinson, Franklin Lakes, USA) were used.

    Techniques:

    Thyroid–hormone-induced activation of β-lactamase and of α-complementation of β-galactosidase. Colorimetric monitoring of the β-lactamase-catalyzed hydrolysis of nitrocefin ( A ) and of the β-galactosidase-catalyzed

    Journal:

    Article Title: Regulation of protein activity with small-molecule-controlled inteins

    doi: 10.1110/ps.04996905

    Figure Lengend Snippet: Thyroid–hormone-induced activation of β-lactamase and of α-complementation of β-galactosidase. Colorimetric monitoring of the β-lactamase-catalyzed hydrolysis of nitrocefin ( A ) and of the β-galactosidase-catalyzed

    Article Snippet: Nitrocefin was purchased from Becton-Dickinson and X-gal from Fisher Scientific.

    Techniques: Activation Assay

    Detection of β -lactamase associated with outer membrane vesicles (OMVs) using nitrocefin disk. (1) Penicillin-sensitive Pm 12948 strain; (2) OMVs; and (3) penicillin-resistant Pm 12945 cells.

    Journal: MicrobiologyOpen

    Article Title: Outer membrane vesicles of Pasteurella multocida contain virulence factors

    doi: 10.1002/mbo3.201

    Figure Lengend Snippet: Detection of β -lactamase associated with outer membrane vesicles (OMVs) using nitrocefin disk. (1) Penicillin-sensitive Pm 12948 strain; (2) OMVs; and (3) penicillin-resistant Pm 12945 cells.

    Article Snippet: In order to know if β -lactamase was a contamination from cell debris, OMVs were treated with proteinase K, to digest β -lactamase associated with the outer membrane of the OMVs, and permeabilized with 0.02% Triton X-100 and β -lactamase activity was measured on nitrocefin disks as before.

    Techniques:

    Contribution of efflux pumps and β-lactamase to AMR induced by indole. (A) The effects of PAβN on Amp resistance induced by indole. PAβN (5 μg/ml was added to the agar plate. (B) Expression of the ampC gene and β-lactamase activity in the presence of indole and Amp during growth. Total RNA was isolated from cultures after 36 h of incubation with 50 or 75 μg/ml Amp or 1 mM indole or both of these. Exponentially growing cells were treated with Amp or indole for 3 h. Following incubation, β-lactamase activity was measured. Enzyme activity was measured in nmol min -1 mg -1 nitrocefin hydrolyzed. (C) Amp susceptibility test in P. putida ΔampC and P. aeruginosa ΔampC (PA4110). Exponentially growing cells were serially diluted, and each dilution of the solution was spotted on plates and incubated for 24 h. (D) Amp susceptibility test in P. aeruginosa ΔoprM (PA0427) and ΔmexB (PA0426) and P. aeruginosa MPAO1.

    Journal: Frontiers in Microbiology

    Article Title: Indole-Induced Activities of β-Lactamase and Efflux Pump Confer Ampicillin Resistance in Pseudomonas putida KT2440

    doi: 10.3389/fmicb.2017.00433

    Figure Lengend Snippet: Contribution of efflux pumps and β-lactamase to AMR induced by indole. (A) The effects of PAβN on Amp resistance induced by indole. PAβN (5 μg/ml was added to the agar plate. (B) Expression of the ampC gene and β-lactamase activity in the presence of indole and Amp during growth. Total RNA was isolated from cultures after 36 h of incubation with 50 or 75 μg/ml Amp or 1 mM indole or both of these. Exponentially growing cells were treated with Amp or indole for 3 h. Following incubation, β-lactamase activity was measured. Enzyme activity was measured in nmol min -1 mg -1 nitrocefin hydrolyzed. (C) Amp susceptibility test in P. putida ΔampC and P. aeruginosa ΔampC (PA4110). Exponentially growing cells were serially diluted, and each dilution of the solution was spotted on plates and incubated for 24 h. (D) Amp susceptibility test in P. aeruginosa ΔoprM (PA0427) and ΔmexB (PA0426) and P. aeruginosa MPAO1.

    Article Snippet: The reaction was initialized by adding cell lysate contained β-lactamase to the reaction mixture containing 25 μg nitrocefin (abcam) and PBS (pH 7.0), and the total volume for each reaction was 1 ml.

    Techniques: Expressing, Activity Assay, Isolation, Incubation

    AmpC activity is increased in dacB mutants but not in LT mutants. Nitrocefin hydrolysis activity assays of P. aeruginosa mutants grown under basal conditions (A) and induced conditions (medium supplemented with 50 μg/ml cefoxitin) (B) were conducted.

    Journal: Antimicrobial Agents and Chemotherapy

    Article Title: Changes to Its Peptidoglycan-Remodeling Enzyme Repertoire Modulate ?-Lactam Resistance in Pseudomonas aeruginosa

    doi: 10.1128/AAC.00268-13

    Figure Lengend Snippet: AmpC activity is increased in dacB mutants but not in LT mutants. Nitrocefin hydrolysis activity assays of P. aeruginosa mutants grown under basal conditions (A) and induced conditions (medium supplemented with 50 μg/ml cefoxitin) (B) were conducted.

    Article Snippet: Nitrocefin hydrolysis assays were performed in 250-μl reaction mixtures of 50 mM sodium phosphate (pH 7.0) containing 10 μg total protein and 20 μg/ml nitrocefin (VWR International, Mississauga, Ontario, Canada).

    Techniques: Activity Assay

    (A) Ethidium bromide (EtBr) loading in the wild-type, Δ rsaF a F b , Δ rsaF a F b rsaA , and Δ acrAB2-nodT strains. Fluorescence at 605 nm was monitored for 60 min to detect the amount of EtBr remaining inside the cell. Curves and error bars represent the averages and standard deviations, respectively, from three biological replicates. The nitrocefin hydrolysis assay was performed with samples incubated in (B) PIPES or (C) PIPES with 120 μM polymyxin B nonapeptide (PMXBN) for 360 min at room temperature. Absorbance at 490 nm ( A 490 ) was measured every 3 min to monitor nitrocefin hydrolysis. The average and standard deviation from three biological replicates are plotted. a.u., arbitrary units.

    Journal: Applied and Environmental Microbiology

    Article Title: Two Outer Membrane Proteins Contribute to Caulobacter crescentus Cellular Fitness by Preventing Intracellular S-Layer Protein Accumulation

    doi: 10.1128/AEM.02479-16

    Figure Lengend Snippet: (A) Ethidium bromide (EtBr) loading in the wild-type, Δ rsaF a F b , Δ rsaF a F b rsaA , and Δ acrAB2-nodT strains. Fluorescence at 605 nm was monitored for 60 min to detect the amount of EtBr remaining inside the cell. Curves and error bars represent the averages and standard deviations, respectively, from three biological replicates. The nitrocefin hydrolysis assay was performed with samples incubated in (B) PIPES or (C) PIPES with 120 μM polymyxin B nonapeptide (PMXBN) for 360 min at room temperature. Absorbance at 490 nm ( A 490 ) was measured every 3 min to monitor nitrocefin hydrolysis. The average and standard deviation from three biological replicates are plotted. a.u., arbitrary units.

    Article Snippet: Nitrocefin was purchased from Cayman Chemical (Ann Arbor, MI), and a 30-mg/ml stock solution was made in dimethyl sulfoxide (DMSO).

    Techniques: Fluorescence, Hydrolysis Assay, Incubation, Standard Deviation

    Biochemical analysis of relebactam inhibition of M. abscessus β -lactamase, Bla Mab . Our novel Thin Layer Chromatography (TLC) assay (2a) exhibiting the activity of Bla Mab in the turnover of penicillin V (high R f value) to penicilloic acid (lower R f value). In the absence, or termination of activity of Bla Mab (by boiling (100 °C) for 1 h) or addition of known inhibitor avibactam ( Lefebvre et al., 2017 ) (200 μg/mL) no lower R f value spot corresponding to penicilloic acid is seen on the TLC plate. The addition of relebactam to the reaction between Bla Mab and penicillin V also results in the absence of the lower Rf value spot, suggesting inhibition of Bla Mab (2a). This observed inhibition is validated by a spectrophotometric analysis, where the turnover of nitrocefin (100 μM) by Bla Mab (0.25 nM) was monitored at 486 nm with a varying concentration of relebactam (0, 0.1, 1, 10 and 100 μM). The increase in concentration of relebactam resulted in partial inhibition of nitrocefin turnover at 1 μM and total abrogation at 10 μM (2b). The initial velocity (v i ) of the reaction between Bla Mab and nitrocefin was monitored for a range of substrate concentrations (1-500 μM) and relebactam concentrations (0, 0.5, 0.75, 1 and 2.5 μM). This data was plotted v i vs [S] in order to determine K m values (2c/f). The values for K obs were obtained as previously described ( Dubée et al., 2014 ) and plotted against relebactam concentrations ([I]) to deduce a carbamylation rate ( K 2 / K i ) for Bla Mab (2d). The kinetics of Bla Mab decarbamylation were assessed to show the recovery of nitrocefin hydrolysis by Bla Mab after inhibition by relebactam in order to derive a K off value (2e). Kinetic parameters were derived as described previously (2f) ( Dubée et al., 2014 ).

    Journal: bioRxiv

    Article Title: Combining amoxicillin and relebactam provides a new therapeutic option for Mycobacterium abscessus infection

    doi: 10.1101/563189

    Figure Lengend Snippet: Biochemical analysis of relebactam inhibition of M. abscessus β -lactamase, Bla Mab . Our novel Thin Layer Chromatography (TLC) assay (2a) exhibiting the activity of Bla Mab in the turnover of penicillin V (high R f value) to penicilloic acid (lower R f value). In the absence, or termination of activity of Bla Mab (by boiling (100 °C) for 1 h) or addition of known inhibitor avibactam ( Lefebvre et al., 2017 ) (200 μg/mL) no lower R f value spot corresponding to penicilloic acid is seen on the TLC plate. The addition of relebactam to the reaction between Bla Mab and penicillin V also results in the absence of the lower Rf value spot, suggesting inhibition of Bla Mab (2a). This observed inhibition is validated by a spectrophotometric analysis, where the turnover of nitrocefin (100 μM) by Bla Mab (0.25 nM) was monitored at 486 nm with a varying concentration of relebactam (0, 0.1, 1, 10 and 100 μM). The increase in concentration of relebactam resulted in partial inhibition of nitrocefin turnover at 1 μM and total abrogation at 10 μM (2b). The initial velocity (v i ) of the reaction between Bla Mab and nitrocefin was monitored for a range of substrate concentrations (1-500 μM) and relebactam concentrations (0, 0.5, 0.75, 1 and 2.5 μM). This data was plotted v i vs [S] in order to determine K m values (2c/f). The values for K obs were obtained as previously described ( Dubée et al., 2014 ) and plotted against relebactam concentrations ([I]) to deduce a carbamylation rate ( K 2 / K i ) for Bla Mab (2d). The kinetics of Bla Mab decarbamylation were assessed to show the recovery of nitrocefin hydrolysis by Bla Mab after inhibition by relebactam in order to derive a K off value (2e). Kinetic parameters were derived as described previously (2f) ( Dubée et al., 2014 ).

    Article Snippet: Biochemical analysis of BlaMab inhibition by Relebactam Recombinant BlaMab (0.25 nM) was mixed with an increasing concentration of relebactam (0, 0.1, 1, 10 and 100 μM) and 100 μM nitrocefin (Carbosynth, UK).

    Techniques: Inhibition, Thin Layer Chromatography, Activity Assay, Concentration Assay, Derivative Assay

    SnoopRing and PilinRing cyclization conferred thermal resilience. ( A ) Cyclization decreased heat-induced aggregation. BLA, Pilin-C-BLA-Isopeptag and SnoopTag-BLA-SnoopCatcher were heated at the indicated temperature for 10 min, centrifuged, and the supernatant analyzed by SDS-PAGE with Coomassie staining. C is control without incubation. ( B ) Plot of heat-induced aggregation, from quantifying SDS-PAGE. ( C ) Cyclization enhanced the catalytic activity following heating. BLA, SnoopTag-BLA-SnoopCatcher, Pilin-C-BLA-Isopeptag and SpyTag-BLA-SpyCatcher were incubated for 10 min at the indicated temperature, before returning to RT and then running a nitrocefin colorimetric activity assay. The initial rates of reaction were calculated using the linear portion of the enzyme curves. Data were normalized using the initial rate of reaction at 25 °C as 100% recovered activity. (All are mean of triplicate ± 1 s.d.; some error bars are too small to be visible.)

    Journal: Scientific Reports

    Article Title: SpyRing interrogation: analyzing how enzyme resilience can be achieved with phytase and distinct cyclization chemistries

    doi: 10.1038/srep21151

    Figure Lengend Snippet: SnoopRing and PilinRing cyclization conferred thermal resilience. ( A ) Cyclization decreased heat-induced aggregation. BLA, Pilin-C-BLA-Isopeptag and SnoopTag-BLA-SnoopCatcher were heated at the indicated temperature for 10 min, centrifuged, and the supernatant analyzed by SDS-PAGE with Coomassie staining. C is control without incubation. ( B ) Plot of heat-induced aggregation, from quantifying SDS-PAGE. ( C ) Cyclization enhanced the catalytic activity following heating. BLA, SnoopTag-BLA-SnoopCatcher, Pilin-C-BLA-Isopeptag and SpyTag-BLA-SpyCatcher were incubated for 10 min at the indicated temperature, before returning to RT and then running a nitrocefin colorimetric activity assay. The initial rates of reaction were calculated using the linear portion of the enzyme curves. Data were normalized using the initial rate of reaction at 25 °C as 100% recovered activity. (All are mean of triplicate ± 1 s.d.; some error bars are too small to be visible.)

    Article Snippet: 3 nM of BLA construct was allowed to react with 100 μM nitrocefin (Merck) in 0.1 M NaH2 PO4 pH 7.0 with 1 mM EDTA at 20 °C.

    Techniques: SDS Page, Staining, Incubation, Activity Assay

    Beta-lactamase production in ceftazidime and tazobactam-piperacillin resistant isolates. Activity was measured using nitrocefin, in a chromogenic assay by calculating the change in A486/390 per minute. The dashed line indicates the value of the negative control (PAO1). Ceftazidime (CAZ); piperacillin/tazobactam (TZP). Bars indicate standard error

    Journal: BMC Microbiology

    Article Title: Evolutionary diversification of Pseudomonas aeruginosa in an artificial sputum model

    doi: 10.1186/s12866-016-0916-z

    Figure Lengend Snippet: Beta-lactamase production in ceftazidime and tazobactam-piperacillin resistant isolates. Activity was measured using nitrocefin, in a chromogenic assay by calculating the change in A486/390 per minute. The dashed line indicates the value of the negative control (PAO1). Ceftazidime (CAZ); piperacillin/tazobactam (TZP). Bars indicate standard error

    Article Snippet: Cultures were grown in LB to an Absorbance at 600 nm of 0.3, and nitrocefin (Merck-Millipore) was added to a final concentration of 51.6 μg ml−1 .

    Techniques: Activity Assay, Chromogenic Assay, Negative Control

    Suppression efficiency of four-base codon/tRNA pairs measured by nitrocefin turnover. See Materials and Methods for definition of units. Readthrough of UAG, AGGA, CCCU, CUAG and UAGA was 0.8–1.7 units, while TOP10 cells alone exhibit about 0.9 unit. Suppression of four-base codons resulted in 17–240 units of activity, compared to 970 for suppression of UAG by supD . Results are the average of three to five independent trials per data point.

    Journal: Journal of Molecular Biology

    Article Title: Expanding the genetic code: selection of efficient suppressors of four-base codons and identification of “shifty” four-base codons with a library approach in Escherichia coli 1

    doi: 10.1006/jmbi.2001.4518

    Figure Lengend Snippet: Suppression efficiency of four-base codon/tRNA pairs measured by nitrocefin turnover. See Materials and Methods for definition of units. Readthrough of UAG, AGGA, CCCU, CUAG and UAGA was 0.8–1.7 units, while TOP10 cells alone exhibit about 0.9 unit. Suppression of four-base codons resulted in 17–240 units of activity, compared to 970 for suppression of UAG by supD . Results are the average of three to five independent trials per data point.

    Article Snippet: Cells were grown in 2YT to A 600 between 0.5 and 1.5 (mid to late-log phase), washed with 50 mM sodium phosphate buffer (pH 7) containing 10 % (w/v) DMSO, and assayed with 1 mM nitrocefin (Oxoid).

    Techniques: Activity Assay