Optical and magnetic properties of pseudomonas azurins

Brill, Arthur S.; Bryce, Graeme F.; Maria, H. J.

doi:10.1016/0005-2795(68)90048-2

Cited by 80 publications

(36 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Pseudomonas blue protein, which contains a single Cu2+, has been found to have Cotton effects in the visible region of its optical rotatory dispersion curve [8]. Anomalous dispersion in the region of Cuz+ absorption has also been reported for ceruloplasmin [9], and we will here present similar findings with fungal laccase.…”

supporting

confidence: 81%

“…Comparison with the results for ceruloplasmin [9] and bacterial blue proteins (azurin) [8,13] suggest that all the "blue" proteins, whether they contain one (as in the bacterial proteins) or several forms of copper (as in the "blue" oxidase), have a chromophoric Cu2+ in very similar, asymmetric coordinations. Azurin, for example, has its absorption bands a t 460, 625 and 780 nm.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

An Optical Rotatory Dispersion Investigation of Fungal Laccase

Bossa

Rotilio

Fasella

et al. 1969

European Journal of Biochemistry

View full text Add to dashboard Cite

The optical rotatory dispersion curves for fungal laccase A and B have been determined in the wavelength region 200–750 nm. Both proteins show pronounced Cotton effects in the visible region. These are discussed in terms of possible chromophores (the so‐called Type 1 and Type 2 Cu2+ as well as the two diamagnetic copper ions). Various chemical treatments indicate that the anomalous dispersion is mainly associated with the blue, Type 1 Cu2+, which is thus coordinated in an asymmetric manner, but a small contribution from the Type 2 Cu2+ cannot be excluded. There are several Cotton effects in the ultraviolet region, probably associated with aromatic amino acids and peptide bonds in α‐helical configuration, but possible contributions from carbohydrates and disulfide bridges are also considered. The curves in the ultraviolet region do not change on complete reduction of the enzyme, indicating that there are no gross conformational changes on reduction and that the groups giving rise to the anomalous dispersion in this region are not associated with the electron‐accepting sites.

show abstract

supporting

confidence: 81%

Section: Discussionmentioning

confidence: 99%

An Optical Rotatory Dispersion Investigation of Fungal Laccase

Bossa

Rotilio

Fasella

et al. 1969

European Journal of Biochemistry

View full text Add to dashboard Cite

show abstract

“…One effect of introducing this different ligand would be to lower the symmetry of the g-tensor from axial to rhombic, thus modifying the EPR spectrum, but in actual fact the rhombicity appears to be small. Of the two blue proteins considered here, stellacyanin has three distinct values of g [14], the g tensor for azurin being axial within the limits of resolution [41,26]. Linear electric field effect experiments are, however, more sensitive to the presence of an odd ligand with different bonding properties than standard EPR experiments and would emphasize the inequivalence of the ligands more strongly.…”

Section: Resultsmentioning

confidence: 99%

“…Stellacyanin was isolated according to Mims and Peisach [25] from acetone powders of Rhus vernicifera lac prepared by Saito and Company, Tokyo. Both of the proteins were 5 mM in Cu(I1) based on optical spectral criteria [14,26].…”

Section: Methodsmentioning

confidence: 99%

The Linear Electric Field Effect in Stellacyanin, Azurin and in Some Simple Model Compounds

Peisach

Mims²

1978

European Journal of Biochemistry

View full text Add to dashboard Cite

All mononuclear Cu(I1) sites in frozen solution are non-centrosymmetric and, unless physically constrained, will have a tetrahedral distortion away from the usual square planar structure often presented for Cu(I1) complexes. Blue copper sites such as are found in azurin and stellacyanin have a greater distortion towards a tetrahedral geometry than do simple Cu(I1) complexes. The distortion is comparable to that which is observed for Cu(I1)-o-phenanthroline dichloride, a known tetrahedral complex. Blue copper sites possess an axis of asymmetry directed away from gll which could arise from a metal-sulfur interaction.

show abstract

“…Absorption spectra were recorded as described previously (O'Keeffe & Anthony, 1980), and the concentrations of blue copper proteins and cytochromes c were calculated from spectra by using the following wavelength pairs and millimolar absorption coefficients: azurin from Pseudomonas aeruginosa (625 nm -500 nm, 3.5 mM-1 cm-; Brill et al, 1968); 'azurin' from organism 4025 (620 nm-500 nm, 16 mM-1 cm-1); amicyanin from organism 4025 (620 nm -500 nm, 3.8mmM-lcm-'). Absorption coefficients for the cytochromes c of Pseudomonas AM1 and Methylophilus methylotrophus were taken from O'Keeffe & Anthony (1980) and Cross & Anthony (1980) respectively.…”

Section: Buffer Solutionsmentioning

confidence: 99%

The role of blue copper proteins in the oxidation of methylamine by an obligate methylotroph

Lawton¹,

Anthony²

1985

Biochemical Journal

View full text Add to dashboard Cite

Organism 4025, an obligate methylotroph, when grown on methylamine in the presence of a high concentration of copper, contained high concentrations of methylamine dehydrogenase and two blue copper proteins, amicyanin and an azurintype protein; these were purified to homogeneity and characterized. The methylamine dehydrogenase is a basic protein (pI8.8) and consists of light and heavy subunits (Mr 14100 and 43000; total Mr 112000). This dehydrogenase differed slightly from other methylamine dehydrogenases in its absorption spectrum and in its lack of thermal stability. Amicyanin, the more abundant blue copper protein, had an Mr of 11 500, a midpoint redox potential of 294mV at pH 7.0, and a much lower isoelectric point (pl 5.3) than other amicyanins. Its absorption maximum was 620nm (7-24nm higher than those of other amicyanins); its absorption coefficient (at 620nm) was 3.8 mm-'1 cm-'. The 'azurin' (6% of the blue copper protein) had an Mr of 12 500, a midpoint redox potential of 323 mV and a high isoelectric point (pl 9.4). Its absorption maximum was 620 nm, the absorption coefficient (16mM-1 cm-') at this wavelength being considerably greater than that of any blue copper protein described previously. The partially-purified soluble cytochromes CH and CL were similar to those of other methylotrophs. The interactions of the purified redox proteins were investigated in order to elucidate their role in methylamine oxidation. Methylamine dehydrogenase was able to donate electrons only to amicyanin, the rate of reaction being 2.04mmol/min per jumol of methylamine dehydrogenase; this is sufficient to account for the rate of respiration in whole bacteria. The blue copper proteins were able to react rapidly with each other and with both the soluble cytochromes c.

show abstract

Optical and magnetic properties of pseudomonas azurins

Cited by 80 publications

References 18 publications

An Optical Rotatory Dispersion Investigation of Fungal Laccase

An Optical Rotatory Dispersion Investigation of Fungal Laccase

The Linear Electric Field Effect in Stellacyanin, Azurin and in Some Simple Model Compounds

The role of blue copper proteins in the oxidation of methylamine by an obligate methylotroph

Contact Info

Product

Resources

About