Pseudomonas aeruginosa cytochrome

B. Structure of Cytochrome c Peroxidase from Pseudomonas aeruginosa... 

Pseudomonas aerogenes ferredoxin, 33 55-56 Pseudomonas aeruginosa bacfer iron cores, 36 452 diheme cytochrome c peroxidase, 36 242-245... 

Akey, C. E., Moffat, K., Wharton, D. C., and Edelstein, S. j. (1980). Characterization of crystals of a cytochrome oxidase (nitrite reductase) from Pseudomonas aeruginosa by X-ray diffraction and electron microscopy. . Mol. Biol. 136, 19-43. 

Berger, H., and Wharton, D. C. (1980). Small-angle X-ray scattering studies of oxidized and reduced cytochrome oxidase from Pseudomonas aeruginosa. Biochim. Biophys. Acta 622, 355-359. 

Brunori, M., Parr, S. R., Greenwood, C., and Wilson, M. T. (1975). A temperature-jump study of the reaction between azurin and cytochrome c oxidase from Pseudomonas aeruginosa. Biochem. J. 151, 185-188. 

Greenwood, C., Barber, D., Parr, S. R., Antonini, E., Brunori, M., and Colosimo, A. (1978). The reaction of Pseudomonas aeruginosa cytochrome c-551 oxidase with oxygen. Biochem.J. 173, 11-17. 

Several of these cytochromes use nitrogen compounds as electron acceptors. Cytochrome cdx from Pseudomonas aeruginosa is a greenish-brown soluble enzyme which contains one c and one chlorin dx) heme in each of two subunits of 63 000 molecular weight. The presence of four redox centres is appropriate for the efficient catalysis of the four-electron reduction of dioxygen to water. It appears, however, that its physiological role may be the reduction of nitrite to NO. Kinetic studies on the anaerobic reduction of cd, by Fe(EDTA)2- have focused attention on electron transfer between the heme groups in the enzyme.722... 

The cytochrome o from Azotobacter vinelandii is reported to consist of one polypeptide of molecular weight 28 000 with two identical heme components. It has also been isolated from the thermophile PS3,1319 Escherichia coli, Vitreoscilla, Pseudomonas aeruginosa, and Rhodopseudomonas spp. The enzyme from Vitreoscilla consists of two identical polypeptides of molecular weight 13 000 and two moles of protoheme IX. A cytochrome b562-o complex from E. coli contains two peptides and, strangely, copper.1320... 

Fiilop V, Ridout CJ, Greenwood C et al (1995) Crystal-structure of the di-heme cytochrome-c peroxidase from Pseudomonas aeruginosa. Structure 3 1225-1233... 

IN SITU AND AFM OF SINGLE-METAL METALLOPROTEINS HORSE HEART CYTOCHROME C AND PSEUDOMONAS AERUGINOSA AZURIN... 

Dihaem cytochrome c peroxidase (Pseudomonas aeruginosa) haem B (His) None 3.1.1.1. 

Finally, as usual, bacteria provide an exception to the general rule. In this case the di-haem cytochrome c peroxidase from Pseudomonas aeruginosa removes its electron, not from a porphyrin, nor an amino acid, but instead from a separate high-potential haem, which is converted from Fe11 to Fe111 [22]. This proves that, at least for peroxidases, nature can manage very well without protein-bound free radicals if necessary. 

Fig. 8. MCD spectra of ferryl iron. Low-temperature (50 or 100K) MCD spectra of ferryl iron in different proteins HRPCII, horse-radish peroxidase compound II HRPCX, horse-radish peroxidase compound X YCCP, yeast cytochrome c peroxidase compound I PsCCP, compound I of the dihaem cytochrome c peroxidase from Pseudomonas aeruginosa-, Mb pH 3.5, ferryl myoglobin formed at pH 3.5 MbpD9.0, the same compound found at pD9.0. Note the similarity of all the spectra with the exception of the alkaline form of ferryl myoglobin. Reprinted with permission from Cheesman, M.R., Greenwood, C. and Thomson, A.J. (1991) Adv. Inorg. Chem. 36, 201-255.

MCD spectra perhaps provide the best fingerprint for the existence of an FeIV=0 structure. Fig. 8 shows that there is a great similarity between the spectra of horseradish peroxidase compound II, horseradish peroxidase compound X, cytochrome c peroxidase compound I, Pseudomonas aeruginosa peroxidase compound I and ferryl myoglobin at acid pH. Similar features are seen in the spectra of catalase [170] and myoglobin [171] compound II. 

Peroxidases fall into two superfamilies (plant and mammalian) and a third, indistinct group that includes chloroperoxidase (a P450-like hybrid) and di-heme cytochrome c peroxidase from Pseudomonas aeruginosa. The plant peroxidase superfamily contains enzymes of plant, fungal, and bacterial origin [126], Mammalian peroxidases make up the second superfamily, and include lactoperoxidase, myeloperoxidase, and prostaglandin H synthase. Both families have been the focus of numerous excellent reviews, several of which have discussed the differences between the plant and mammalian peroxidases [126-130], Here, recent experimental investigations focused on the plant peroxidases will be discussed. 

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