Biochem- Proteins Flashcards
Where in the GI tract does protein digestion begin (mouth, stomach, duodenum, ileum, colon)?
Stomach
What does the pancreatic proteases cleave the proteins into in the duodenum?
oligopeptides and amino acids
Which enzymes on the brush border in the SI cleave the oligopeptides into amino acids?
aminopeptidases
What 2 things are secreted into the duodenum by the pancreas when the gastric contents enter it?
biocarbonate and zymogens
What is the enzyme that is secreted by the brush border to activate trypsinogen –> trypsin?
Enteropeptidase
What 3 zymogens does trypsin cleave to activate?
Chymotrypsinogen, protealase, procarboxypeptidases
A negative N balance with lack of essential AA consumption can lead to which disease, despite adequate caloric intake?
Kwashiorkor
What is the problem with zymogens if the pancratic duct is blocked in pancreatitis?
They get activated b4 they reach the duodenum –> destroy surrounding cells + decreased intestinal protein digestion
This is the condition characterized by anemia, chronic diarrhea, fatigue, and bloating, and is caused by an immune response to gluten.
Celiac disease (glutarded)
This is the condition characterized by defective chloride channels, leading to viscious pancreatic secretions and thus inadequate protein digestion.
Cystic fibrosis
AA’s are absorbed from the lumen into the eintestinal epithelial cell using what ion for secondary active transport?
Na+
This is the condition characterized by photosensitivity, ataxia, nystagmus, and tremor, and is caused by defective intestinal and renal epthelial absorption of proteins.
Hartnup disease
This is the condition characterized by cysteine stones in their usine from defective absorption from their renal epithelial cells.
Cystinuria
This is the organelle that uses autophagy tp eat ingest proteins.
Lysosomes
What is the family of proteases that degrades the protiens into individual amino acids within the lysosomes?
Cathepsin
What is the point of autophagy in times of starvation?
to eat old proteins so u can build new proteins for survival.
This is a small protien that targets itnracelliular proteins for degredation by covalently binding to the amino group of lysine residues.
Ubiquitin
The ubiquitin-targeted protein is then degraded by the binding of what structure?
Proteasome
The gamma-glutamyl cycle is necessary to the synthesis of what molecule?
Glutathione
Glutathione protects the cells from what type of damage?
oxidative dmg
The gamma-glyamyl cycle is the dependent on the salvage of of what AA?
Cysteine
