BCCB2002 Lecture Notes - Lecture 5: Nitrogen Balance, Transamination, Creatinine
Document Summary
Nitrogen balance: the relationship between nitrogen being put in to the body and nitrogen removed from the body. Nucleotides from dna (from meat: loss. Urine urea, creatinine, uric acids and ammonia. Hair: deficiency occurs when there is not enough intake to replace losses. Symptoms include changes in plasma protein and eventually loss in muscle mass, as muscle protein will be broken down to make proteins in the body to tissues that need it more. What can be controlled to maintain nitrogen balance: sufficient dietary intake, oxidation to remove excess nitrogen. Difference between protein metabolism and amino acid metabolism: protein. Breakdown occurs in acidic environment of stomach, activating pepsinogen which denatures proteins: amino acid. How excess amino acids can be metabolised: oxidation, involving the removal of nh2 group and transamination. Involves alpha-ketoglutarate as a substrate and glutamate as a product. Transfer of amino group to alpha-ketoglutarate to form an amino acid.
