Pseudocatalase manganese

In 1983, Kono and Fridovich reported the isolation of a pseudocatalase from L. plantarum which contained manganese (159). The enzyme was 172 kDa the original report gave a subunit of 28.3 kDa and 1.12 0.37 atoms of manganese per subunit. The visible spectrum of the enzyme displayed an absorption maximum at 470 nm (e = 1.35 x 103 M l cm-1) with shoulders at 398 and 500 nm. This spectrum is extremely similar to those of Mn superoxide dismutases (Section II,A) and, thus, indicative of the presence of Mn(III). Comparison of the amino acid compositions of the two enzymes suggested that they are not closely related. The pseudocatalase possessed no superoxide dismutase activity but had a turnover number of 3.9 x 10s mol of peroxide per mole of enzyme per second. 

Beyer, W.F. and Fridovich, I. 1985. Pseudocatalase from Lactobacillus plantation Evidence for a homopentameric structure containing two atoms of manganese per subunit. Biochem. 24, 6460-6467. 

Manganese catalases, sometimes referred to as pseudocatalases, are found in lactic acid bacteria and in thermophihc bacteria. The molecular weight of these enzymes ranges from 170 to 210 kDa. They may form unusual ohgomeric structures like homopentamers and homohexamers. Unhke heme catalases, they are not inhibited by CN or Nj [ 197 ]. 

Manganese complexes as models for manganese-containing pseudocatalase enzymes Synthesis, structural and catalytic activity studies... 

Kono Y, Eridovich I. 1983. Isolation and characterization of the pseudocatalase of Lactobacillus plantarum A new manganese-containing enzyme. J Biol Chem 258 6015-6019. 

No lactic acid bacteria possess cytochrome. The catalase activity is generally assumed not to exist, but several species of bacteria (Lactobacillus, Pediococcus and Leuconostoc) can synthesize a manganese-dependent, non-hemic pseudocatalase. A hemic catalase activity has been identified in many strains. 

---