Isomers that have opposite configurations at one or more of the chiral centers but that are not mirror images of each other are called diastereomers

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#Id: 8545

#XL - Q Biochemistry

Irreversible inhibitors, such as the organophosphorus and organomercury compounds, cyanide, carbon monoxide and hydrogen sulphide, combine with the enzyme to form a covalent bond. 

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#Id: 8546

#XL - Q Biochemistry

The extent of irreversible inhibition of the enzyme is dependent upon the reaction rate constant (and hence time) for covalent bond formation and upon the amount of inhibitor present.

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#Id: 8547

#XL - Q Biochemistry

The irreversible inhibitors cannot be removed by simple physical techniques such as dialysis, is to reduce the amount of enzyme available for reaction.

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#Id: 8548

#XL - Q Biochemistry

TLS Online TPP Program

#Id: 8549

#XL - Q Biochemistry

The irreversible inhibition involves reactions with a functional group, such as hydroxyl or sulphydryl, or with a metal atom in the active site or a distinct allosteric site.

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#Id: 8550

#XL - Q Biochemistry

diisopropylphosphofluoridate, reacts with a serine OH group in the active site of esterases such as acetylcholinesterase/chymotrypsin, whilst the organomercury compound p-hydroxymercuribenzoate reacts with a cysteine group, in both cases resulting in covalent bond formation and enzyme inhibition.