Beef liver catalase

The visible spectra of beef liver catalase (Type A) and its two active peroxide compounds are shown in Fig. 4. The unliganded enz5une has a Soret band at 405 nm (FmM/heme 120) and a characteristic visible... 

Fig. 4. Visible spectra of catalase, compound I, and compound II 5 [xM (heme) beef liver catalase (Boehringer-Mannheim) in 0.1 M potassium phosphate buffer pH 7.4, 30°C. Compound I was formed by addition of a slight excess of peroxoacetic acid. Compound II was formed from peroxoacetic acid compound I by addition of a small excess of potassium ferrocyanide. Absorbance values are converted to extinction coefficients using 120 mM for the coefficient at 405 nm for the ferric enzyme (confirmed by alkaline pyridine hemochromogen formation). Spectra are corrected to 100% from occupancies of f 90% compound I, 10% ferric enzyme (steady state compound I) and 88% compound II, 12% compound I (steady state compound II). The extinction coefficients for the 500 to 720 nm range have been multiplied by 10. Unpublished experiments (P.N., 1999).

Figure 16-11 (A) Stereo drawing showing folding pattern for beef liver catalase and the positions of the NADPH (upper left) and heme (center). From Fita and Rossmann.198 (B) Diagram of proposed structure of an Fe(III)-OOH ferric peroxide complex of human catalase (see also Fig. 16-14).

Figure 1. Active site structures of (a) cytochrome P450cam (PDB 2CPP), (b) beef liver catalase (PDB 4BLC), and (c) horseradish peroxidase (HRP) (PDB 1ATJ).

In the case of beef liver catalase, distal histidine (His74) is believed to serve as a general acid-base catalyst to facilitate the heterolytic 0—0 bond of hydroperoxide bound to the heme (Scheme 2) (21). The Asnl47 residue located near the heme could assist the heterolysis by making the distal site into a polar atmosphere. The same acid-base mechanism has been attributed to peroxidases... 

Chemical synthesis and isolation of 2-keto-6-hydroxyhexanoic acid required several steps. In a second, more convenient process (Fig. 2), the ketoacid was prepared by treatment of racemic 6-hydroxynorleucine [produced by hydrolysis of 5-(4-hydroxybutyl)hydantoin (3)] with D-amino acid oxidase and catalase. After the e.e. of the remaining L-6-hydroxynorleucine had risen to >99%, the reductive animation procedure was used to convert the mixture containing 2-keto-6-hydroxyhexanoic acid and L-6-hydroxynorleucine entirely to L-6-hy-droxynorleucine with yields of 91-97% and e.e. of >98%. Sigma porcine kidney D-amino acid oxidase and beef liver catalase or Trigonopsis variabilis whole cells (source of oxidase and catalase) were used successfully for this transformation [22],... 

Murthy MRN, Reid TJ III, Sicignano A et al (1981) Structure of beef liver catalase. J Mol Biol... 

Abe K, Makino N, Anan FK (1979) pH dependency of kinetic-parameters and reaction-mechanism of beef-liver catalase. J Biochem 85 473-479... 

Mn Catalase. The majority of known catalases contain a heme prosthetic group to catalyze the disproportionation of hydrogen peroxide. These enzymes are long established (e.g., the beef liver catalase was crystallized in 1937 (13)) and are believed to protect respiring cells... 

The reaction mixture contained 50 mM sodium acetate (pH 5.4), 200 mM NaQ, 0.5 mM NEM, 100 p.g/mL beef liver catalase, 50 fiM Dabsyl-Gly-Phe-Gly, 2 mM ascorbate, and CuS04 concentrations varying in the micromolar range depending on enzyme source being assayed, and enzyme. 

Only in the coupled oxidation of nitrite using glucose oxidase-glucose- 0 (as H 0 0H generating system) and beef liver catalase, which results in the formation of isotopically enriched nitrate (183a), are the results compatible with an oxygen atom transfer mechanism [Eqs.(28) and (29) ]. Even in this case, alternative interpretations are possible, such as oxidation of nitrite via outer or inner sphere electron transfers [Eqs. 

Isotope Effects in Beef Liver Catalase-Mediated Oxidations ... 

T.J. Reid, M.R. Murthy, A. Sicignano, N. Tanaka, W.D. Musick, and M.G. Rossmann. 1981. Structure and heme environment of beef liver catalase at 2.5 A resolution Proc. Natl. Acad. Sci. USA 78 4767-4771. (PubMed)... 

FIGURE 1.10 Crystals of a variety of proteins. In (a) hexagonal prisms of beef liver catalase. In (b) crystals of oo acid glycoprotein, in (c) Fab fragments of a murine immunoglobulin, and in (d) rhombohedral crystals of the seed storage protein canavalin. 

FIGURE 1.11 Electron micrographs of negatively stained crystals of (a) pig pancreatic a amylase, and (b) beef liver catalase. The dark areas represent solvent filled areas in the crystal, which are replaced by dense heavy metal stain the light areas correspond to protein molecules where the stain is excluded. The underlying periodicity of the crystals is evident here, even after dehydration and staining. 

Early ORD measurements on beef liver catalase showed large Cotton effects in the Soret region, which disappeared upon denaturation (255). No evidence for previously reported (256) Cotton effects near 600 nm could be obtained (255). ORD and CD measurements on bovine liver catalase included also the liganded hemoprotein. Conformational changes in the protein, occurring upon ligand addition, were deduced from data in the ultraviolet region (257). 

Most catalases consist of four subunits of 60,000 mol each and contain one ferri-protoporphyrin IX molecule per subunit. With few exceptions, catalases are found in all but anaerobic organisms. The crystal structure of beef liver catalase has been determined to 2.5 pm resolution ", and the primary sequence is also known. ... 

Source Acetone powder from beef liver Catalase fraction from beef liver Acetone powder from beef liver... 

X-ray crystal structures have been determined for beef-liver catalase and for horseradish peroxidase in the resting, high-spin ferric state. In both, there is a single heme b group at the active site. In catalase, the axial ligands are a... 

L-6-hydroxynorleucine with yields of 91 to 97% and ee > 99%. Sigma porcine kidney D-amino acid oxidase and beef liver catalase or Trigonopsis variabilis whole cells (source of oxidase and catalase) were used successfully for this transformation. 

Figure 11 (a) Ribbon drawing of the beef liver catalase structure (PDB code 7CAT) showing the location of the heme (red) and NADPH... 

In an earlier study Brown" reported that both horseradish peroxidase and beef liver catalase were electroinactive polarographically under anaerobic conditions. However, under conditions which gave rise to the primary hydrogen peroxide complexes of these proteins, a reductive response was observed. Brown attributed these responses to the direct reduction of the respective hydrogen peroxide complexes of peroxidase and catalase." In one other report catalase was reported to be electroinactive at the dropping mercury electrode. ... 

The structure of beef liver catalase is shown in Fig. 2-16 [2], The heme site IS accessible by a channel 3 nm long. The specificity is largely determined by the ability of a substrate to form H-bonding interactions to some amino acids [2]. Unlike peroxidases, the fifth ligand of catalase is tyrosine. The phenyl ring is tilted 42° inwards to the heme plane with an iron-heme distance of 0.22 nm. This suggest that the phenolic side chain is deprotonated and has a localized charge. The reaction cycle with Fe(III) and Fe(IV) is shown in Eq. 2-6. 

Figure 2-16. The structure of beef liver catalase with heme as the active center.

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