Urease
part 6/40 · 62.6 KB total
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The molecular weight is either 480 kDa or 545 kDa for jack-bean urease (calculated mass from the amino acid sequence). 840 amino acids per molecule, of which 90 are cysteine residues.cite-ref-molecular-catalysis-b-2009-10-0[10]
The optimum pH is 7.4 and optimum temperature is 60 °C. Substrates include urea and hydroxyurea.
Bacterial ureases are composed of three distinct subunits, one large catalytic (α 60–76kDa) and two small (β 8–21 kDa, γ 6–14 kDa) commonly forming (αβγ)3 trimers stoichiometry with a 2-fold symmetric structure (note that the image above gives the structure of the asymmetric unit, one-third of the true biological assembly), they are cysteine-rich enzymes, resulting in the enzyme molar masses between 190 and 300kDa.cite-ref-molecular-catalysis-b-2009-10-1[10]
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