SYNTHESIS AND DETERMINATION OF LYCOMARASMIN ACTIVITY OF SOME DERIVATIVES OF ASPARTIC ACID

The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the reactions of formation of the ML and ML2 complexes of both reagents with cadmium(II) ions were determined by graphical analysis and numerical interpretation of the absorbance-pH curves by the modified SQUAD-G program. Optimal conditions were proposed for the spectrophotometric determination of Cd in 10% v/v ethanol medium in the presence of 0.1% w/v Triton X-100 or 1% w/v Brij 35. BrPADAP and ClPADAP are the most sensitive spectrophotometric reagents for the determination of cadmium(II) ions (ε = 1.28-1.44 . 105 mmol-1 cm2 at 560 nm and pH 8.0-9.5) with a high colour contrast in the reaction (Δλmax ~117 nm) and a selectivity similar to that of other N-heterocyclic azodyes (PAR, PAN, etc.).

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Spectrophotometric study of the acid-base and optical properties of the 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-(diethylamino)phenol (BrPADAP, ClPADAP) and their complexation equilibria with zinc(II) ions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19822676 ◽

1982 ◽

Vol 47 (10) ◽

pp. 2676-2691 ◽

Cited By ~ 6

Author(s):

Miroslav Macka ◽

Vlastimil Kubáň

Keyword(s):

Equilibrium Constants ◽

Spectrophotometric Study ◽

Graphical Analysis ◽

Alkaline Media ◽

Acid Base ◽

Ethanol Medium ◽

Triton X ◽

Mixed Water ◽

Derivatives Of

The optical and acid-base characteristics of BrPADAP and ClPADAP were studied in mixed water-ethanol and water-DMF media and in 10% ethanol medium in the presence of cationic, anionic and nonionic tensides. The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the ML and ML2 complexes with zinc(II) ions were found by graphical analysis and numerical interpretation of the absorbance curves by the modified SQUAD-G program. Optimal conditions were found for the spectrophotometric determination of Zn(II) in the presence of 0.1% Triton X-100 or 1% Brij 35 in alkaline media with pH = 6.5-10. BrPADAP and ClPADAP are the most sensitive reagents (ε = 1.3-1.6 . 105 mmol-1 cm2 at 557 and 560 nm, respectively) for the determination of zinc with high colour contrast of the reaction (Δλ = 104 nm) and selectivity similar to that for the other N-heterocyclic azodyes (PAN, PAR, etc.).

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Voltammetric determination of dopamine and norepinphrine on a glassy carbon electrode modified with poly (L-aspartic acid)

Journal of Chemical Sciences ◽

10.1007/s12039-011-0179-z ◽

2012 ◽

Vol 124 (2) ◽

pp. 537-544 ◽

Cited By ~ 19

Author(s):

ZHANGYU YU ◽

XIAOCHUN LI ◽

XUELIANG WANG ◽

XINYING MA ◽

XIA LI ◽

...

Keyword(s):

Aspartic Acid ◽

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Voltammetric Determination ◽

Carbon Electrode

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Determination of the Catalytic Base in Family 48 Glycosyl Hydrolases

Applied and Environmental Microbiology ◽

10.1128/aem.05532-11 ◽

2011 ◽

Vol 77 (17) ◽

pp. 6274-6276 ◽

Cited By ~ 14

Author(s):

Maxim Kostylev ◽

David B. Wilson

Keyword(s):

Aspartic Acid ◽

Site Directed Mutagenesis ◽

Directed Mutagenesis ◽

Thermobifida Fusca ◽

Glycosyl Hydrolases ◽

Content Type ◽

Modeling Data ◽

Partial Activity

ABSTRACTThe catalytic base in family 48 glycosyl hydrolases has not been previously established experimentally. Based on structural and modeling data published to date, we used site-directed mutagenesis and azide rescue activity assays to show definitively that the catalytic base inThermobifida fuscaCel48A is aspartic acid 225. Of the tested mutants, only Cel48A with the D225E mutation retained partial activity on soluble and insoluble substrates. In azide rescue experiments, only the D225G mutation, in the smallest residue tested, showed an increase in activity with added azide.

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