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  2. Catalase - Wikipedia

    en.wikipedia.org/wiki/Catalase

    Catalase is a tetramer of four polypeptide chains, each over 500 amino acids long. [7] It contains four iron-containing heme groups that allow the enzyme to react with hydrogen peroxide. The optimum pH for human catalase is approximately 7, [8] and has a fairly broad maximum: the rate of reaction does not change appreciably between pH 6.8 and 7 ...

  3. Diagnostic microbiology - Wikipedia

    en.wikipedia.org/wiki/Diagnostic_Microbiology

    The catalase test tests whether a microbe produces the enzyme catalase, which catalyzes the breakdown of hydrogen peroxide. Smearing a colony sample onto a glass slide and adding a solution of hydrogen peroxide (3% H 2 O 2) will indicate whether the enzyme is present or not. Bubbling is a positive test while nothing happening is a negative result.

  4. Beta oxidation - Wikipedia

    en.wikipedia.org/wiki/Beta_oxidation

    Enzyme End product Dehydrogenation by FAD: The first step is the oxidation of the fatty acid by Acyl-CoA-Dehydrogenase. The enzyme catalyzes the formation of a trans-double bond between the C-2 and C-3 by selectively remove hydrogen atoms from the β-carbon. The regioselectivity of this step is essential for the subsequent hydration and ...

  5. Enzyme catalysis - Wikipedia

    en.wikipedia.org/wiki/Enzyme_catalysis

    Enzyme catalysis is the increase in the rate of a process by an "enzyme", a biological molecule. Most enzymes are proteins, and most such processes are chemical reactions. Most enzymes are proteins, and most such processes are chemical reactions.

  6. Turnover number - Wikipedia

    en.wikipedia.org/wiki/Turnover_number

    In enzymology, the turnover number (k cat) is defined as the limiting number of chemical conversions of substrate molecules per second that a single active site will execute for a given enzyme concentration [E T] for enzymes with two or more active sites. [1] For enzymes with a single active site, k cat is referred to as the catalytic constant. [2]

  7. Diffusion-limited enzyme - Wikipedia

    en.wikipedia.org/wiki/Diffusion-limited_enzyme

    Most enzymes have a rate around 10 5 s −1 M −1. The fastest enzymes in the dark box on the right (>10 8 s −1 M −1) are constrained by the diffusion limit. (Data adapted from reference [1]) A diffusion-limited enzyme catalyses a reaction so efficiently that the rate limiting step is that of substrate diffusion into the active site, or ...

  8. Katal - Wikipedia

    en.wikipedia.org/wiki/Katal

    The katal (symbol: kat) is that catalytic activity that will raise the rate of conversion by one mole per second in a specified assay system. [1] It is a unit of the International System of Units (SI) [1] used for quantifying the catalytic activity of enzymes (that is, measuring the enzymatic activity level in enzyme catalysis) and other catalysts.

  9. Acatalasia - Wikipedia

    en.wikipedia.org/wiki/Acatalasia

    Acatalasia is an autosomal recessive peroxisomal disorder caused by absent or very low levels of the enzyme catalase. [2] Catalase breaks down hydrogen peroxide in cells into water and oxygen. Low levels of catalase can cause hydrogen peroxide to build up, causing damage to cells.