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Hydrolase
In biochemistry, a hydrolase or hydrolytic enzyme is a class of enzymes that catalyze the hydrolysis of a chemical bond. For example, an enzyme that catalyzed the following reaction is a hydrolase:

$$A-B+H_2O\longrightarrow A-OH +B-H$$

Enzyme families which classify as hydrolases include:
 * Phosphatases - Which act by hydrolyzing products containing phosphorous (ex. ATP + H2O ⇌ ADP + P via ATP Hydrolysis)
 * Esterases - Which act by hydrolyzing ester groups (ex. CH3COOCH2CH3 + H2O ⇌ CH3COOH + CH3CH2OH)
 * Peptidases (Proteases) - Which act by hydrolyzing peptide bonds via proteolysis (ex. HIV protease cleaving Group-specific antigen)
 * Glycosidases - Which act by hydrolyzing polysacchirides (ex. Glycoside Hydrolase)

Metallothionein
Metallothionein (MT) is a family of cysteine-rich, low molecular weight (MW ranging from 500 to 14000 Da) proteins. They may be located in both the cytoplasm and the nucleus of the cell. MTs have the capacity to bind both physiological (such as zinc, copper, selenium) and xenobiotic (such as cadmium, mercury, silver, arsenic) heavy metals through the thiol group of its cysteine residues, which represent nearly 30% of its constituent amino acid residues.

Mechanism
This mechanism is dependent on the pH of the solution. The higher the pH, the higher the activity of the enzyme (due to the ease of the deprotonation step.

A zinc prosthetic group in the enzyme is coordinated in three positions by histidine side-chains. The fourth coordination position is occupied by water, the attached zinc effectively lowers the water's pKa from 15.7 to 7 which generates a hydroxide ion to attack the carbon dioxide. The pH is then lowered by this decrease in pKa, according to Le Chatelier's principle this drives the reaction towards deprotonation. The carbon dioxide molecule then is able to bind to the active site of the enzyme and positioned for optimal interaction.

The hydroxide ion left attached to the zinc is then able to attack the carbonyl of the carbon dioxide effectively converting it to bicarbonate via the nucleophilic attack. The oxygen from the carbon dioxide molecule then is able to form an intermediate bond during this conversion process.

The bicarbonate ion is then released as the enzyme is regenerated with a proton from solution, this enzyme is now ready to facilitate further catalysis of bicarbonate. This quick turnover rate causes the enzyme to be regenerated rather quickly and efficiently, often seen as a kinetically fast process of converting carbon dioxide within blood cells.

Ester Hydrolysis
Mechanisms regarding the hydrolysis of esters under both acidic and basic solution.



Properties of Potassium trifluoroacetate
Potassium trifluoroacetate
 * Molecular formula: CF3COOK
 * Molar mass: 152.11 g/mol
 * Melting point: 140-142 °C
 * Boiling point:
 * Solubility in water: 0.1 g/mL

See Inorganic compound

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