Journal: PLoS ONE

Article Title: A Highly Sensitive Method for Quantitative Determination of L-Amino Acid Oxidase Activity Based on the Visualization of Ferric-Xylenol Orange Formation

doi: 10.1371/journal.pone.0082483

Figure Lengend Snippet: Row 1: 14 background solutions with different pH values from 1 to 14 (from left to right) prepared by a mixture of 6 N HCl and 6 N NaOH; row 2: 14 standard 20 µM H 2 O 2 solutions with different pH values ranging from 1 to 14 (from left to right) adjusted by either HCl or NaOH; row 3: 14 standard 20 µM H 2 O 2 solutions with uniform pH of 7.5; row 4: 14 individual oxidization reactions of L-Leu by LAAO from Psudoalteromonas sp. R3 (R3-LAAO) with different pH values from 1 to 14 (from left to right) adjusted by either HCl or NaOH after oxidation; row 5: 14 individual oxidization reactions of L-Leu by R3-LAAO with uniform pH of 7.5.

Article Snippet: The stereospecific oxidation reaction was performed with 10 mM of each amino acid in 10 mL of R3-LAAO solution harvested from Psudoalteromonas sp. R3 culture supernatant or caLAAO solution (mixture of 1 µL caLAAO with 10 mL of 0.1 M PBS buffer with pH 7.5, Worthington Biochemical Corporation, USA).

Techniques:

Journal: PLoS ONE

Article Title: A Highly Sensitive Method for Quantitative Determination of L-Amino Acid Oxidase Activity Based on the Visualization of Ferric-Xylenol Orange Formation

doi: 10.1371/journal.pone.0082483

Figure Lengend Snippet: On the basis of the diameters of the formed purplish red Fe III XO halos, the concentrations of H 2 O 2 produced by LAAO activities were calculated with the equations in . The corresponding standard H 2 O 2 solutions as indicated above the corresponding holes were used to confirm the accuracy of Fe III XO agar assay. The diameters of the purplish red halos were marked below the holes. Without R3-LAAO, both L-Leu and L-Met (negative controls) did not give purplish red Fe III XO halos (right holes).

Article Snippet: The stereospecific oxidation reaction was performed with 10 mM of each amino acid in 10 mL of R3-LAAO solution harvested from Psudoalteromonas sp. R3 culture supernatant or caLAAO solution (mixture of 1 µL caLAAO with 10 mL of 0.1 M PBS buffer with pH 7.5, Worthington Biochemical Corporation, USA).

Techniques: Produced

Journal: PLoS ONE

Article Title: A Highly Sensitive Method for Quantitative Determination of L-Amino Acid Oxidase Activity Based on the Visualization of Ferric-Xylenol Orange Formation

doi: 10.1371/journal.pone.0082483

Figure Lengend Snippet: LAAO produced by Pseudoalteromonas sp. R3 (R3-LAAO) was used to oxidize the different L-amino acids including L-Cys, L-Glu, L-Asp, L-Val, L-Ala, L-Ser, L-Gly and L-Pro, in separate reactions, and subsequently the produced H 2 O 2 in oxidization solution was measured with both Prussian blue agar assay and Fe III XO agar assay. For the Prussian blue agar assay, the standard H 2 O 2 with concentration of 10 mM was used as the positive control (PC1); in contrast, for the Fe III XO agar assay, the standard H 2 O 2 with concentration of 50 µM was treated as the positive control (PC2). For both assays, the reaction solution without L-amino acid was used as the negative control (NC).

Article Snippet: The stereospecific oxidation reaction was performed with 10 mM of each amino acid in 10 mL of R3-LAAO solution harvested from Psudoalteromonas sp. R3 culture supernatant or caLAAO solution (mixture of 1 µL caLAAO with 10 mL of 0.1 M PBS buffer with pH 7.5, Worthington Biochemical Corporation, USA).

Techniques: Produced, Concentration Assay, Positive Control, Negative Control