GBSN - Biochemistry (Unit 12) Metabolism of Protein

Metabolism of Protein

1. Biochemistry Lecture GBSN (Unit 11) Metabolism of Protein by, Miss Areesha Ahmad Lecturer

2. Characteristics of proteolytic enzymes Proteolytic enzymes, also known as proteases or proteinases, are enzymes that break down proteins by hydrolyzing their peptide bonds. They play crucial roles in various biological processes . Here are some key characteristics of proteolytic enzymes: Substrate Specificity: Proteolytic enzymes are specific for certain peptide bonds in proteins, determined by the amino acid sequence around the bond. Some have broad specificity, while others are highly specific. Active Site : The active site of a proteolytic enzyme contains specific residues critical for its catalytic activity. For example, serine proteases have a serine residue in their active site, which plays a key role in the catalysis . pH Optimum : Proteolytic enzymes have an optimal pH range in which they are most active. For instance, pepsin operates best in the acidic environment of the stomach, while trypsin is most active in the slightly alkaline environment of the small intestine.

3. Regulation: Their activity is tightly regulated by inhibitors, zymogen activation, and other post-translational modifications to prevent unwanted protein degradation. Many proteases are synthesized as inactive precursors (zymogens) that are activated only when needed . Localization : These enzymes can be found in various cellular compartments, including lysosomes, the digestive tract, extracellular spaces, and within cells, each adapted to function in its specific environment . Function : Proteolytic enzymes are involved in numerous biological functions, including digestion of dietary proteins, protein turnover and recycling, blood coagulation, immune response, cell signaling, and apoptosis .

4. Mastication is  the process of chewing and mixing of saliva with the help of tongue and teeth .

5. (The gastric mucosa is  a mucous membrane that lines the stomach's inner surface)

6. Collagen is  the most abundant protein in your body . It is found in the bones, skin and muscles , 

7. (Stabilize blood clots) ( Elastase is  a proteolytic enzyme that breaks down proteins) (Casein protein is  a protein found in milk that gives milk its white color )

8. Hydrolyze: water is mostly used to break down the chemical bonds

9.   Exopeptidase : removes a single amino acid from the carboxyl-terminal of a dietary peptide or protein

10. A peptide bond is  a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O) .  Aliphatic amino acids are  generally a straight chain hydrocarbon Collagen is  the most abundant protein in your body. It is found in the bones, skin and muscles. It provides structural support to the extracellular space of connective tissues

11. Epithelial cells are  a type of cell that form the primary tissues of the body

12. The duodenum, jejunum, and ileum are  the three parts of the small intestine , which is part of the digestive system

13. The seminal vesicles and epididymis are the male reproductive organ Glutathione is  a substance made from the amino acids, It is produced by the liver and involved in including tissue building and repair, making chemicals and proteins needed in the body, and in immune system function.

14. D eamination , an amino group is removed from an amino acid or other compounds.

15. (Ketone group)

16. (Amino group) (Ketone group)

17. (An amine group or amino group is  a functional group that contains a nitrogen atom bonded to one or more alkyl groups and hydrogens )

18. Hydrogen addition (Make ammonia) In presence of water

19. Detoxification is  a process that removes toxic substances from a living organism, such as the human body, through physiological or medicinal means .

20. (Silver nitrate) (Ammonium Chloride)

21. Heating ammonium cyanate can produce urea

22. (bicarbonate) PPi : (inorganic pyrophosphate)

23. Water (H 2 O)  Water is a product of the hydrolysis reactions that occur during the urea cycle . Fumarate , a product of the urea cycle, is incorporated into the citric acid cycle

24. Assignment