Proteins and Enzymes

• The two main stages of protein synthesis are transcription (DNA to mRNA) and translation (mRNA to protein).
• Transcription occurs in the nucleus, while translation takes place on ribosomes in the cytoplasm.
• Enzyme activity can be influenced by pH, temperature, substrate concentration, cofactors, inhibitors, activators, and allosteric regulation.
• Protein structure is determined by primary sequence, secondary structure, tertiary structure, and quaternary structure.
• Primary structure refers to the linear arrangement of amino acids in a polypeptide chain.
• Secondary structure involves local folding patterns such as alpha helices or beta sheets.
• Tertiary structure describes how different parts of a single polypeptide interact with one another.
• Tertiary structure describes how different parts of a single polypeptide chain interact with one another.
• Quaternary structure refers to interactions between multiple polypeptides within a larger complex.
• Quaternary structure refers to interactions between multiple polypeptides to form a functional unit.
• The three-dimensional shape of proteins determines their function.
• Changes in temperature can alter enzyme activity due to changes in protein conformation.
• Ribosomes are responsible for protein synthesis.
• Enzymes are biological catalysts that speed up chemical reactions without being consumed or altered by the reaction.
• Denatured proteins may lose their ability to perform specific functions.