biological chemistry

Introduction to Enzymes: Structure and Characteristics-Short Lecture Notes

Enzymes short notes

Enzymes: Structure and Characteristics
(Introduction to Enzyme Structure & Functions)

What are Enzymes?

There are thousands of chemical reactions in a living system. The chemical reactions in the cell are catalyzed by the biological catalysts called enzymes. Almost all enzymes are highly specialized proteins. (Exception: Ribozymes –Ribozymes are RNA with catalytic activity). The current post we will discuss the Characteristics of Enzymes. We will also discuss the features of a Catalyst and the concept of Activation Energy of a reaction.

What are catalysts?

Ø  The catalyst is substances that accelerate the rate of a chemical reaction.

Ø  The catalyst is not consumed or transformed by the reaction.

Ø  It will not change the equilibrium constant of the reaction.

Ø  Catalysts only change the rate to approach equilibrium constant.

Ø  Catalysts are not required in stoichiometric quantities.

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biological chemistry

Structure of Proteins (Biochemistry Lecture Notes)

protein structure

Protein Structure
(Primary, Secondary, Tertiary & Quaternary Structure of Proteins)

Learning objectives: Protein Structure: Primary Structure, Secondary Structure (Alpha Helix, Beta Plates, Beta Turns), Tertiary Structure, Quaternary Structure, Bonds Stabilizing different Protein Structures.

Protein Structure

Ø  Proteins are the polymers of amino acids. Individual amino acids (residues) are joined by peptide bonds to form the linear polypeptide chain. This linear polypeptide chain is folded into specific structural conformations or simply ‘structure’.  A protein can have up to four levels of structural conformations. Previously we have discussed but the ‘Bonds involved in Protein Structure”. In the present post, we will discuss different types of protein structures.

Ø  A protein can have Four levels of structural organization:

Ø  They are designated as:

(1). Primary Structure

(2). Secondary Structure

(3). Tertiary Structure

(4). Quaternary Structure

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