Digestion of Nucleic Acids By: Kristal, Dandre, and Zack
Nucleic Acids: Genetic information that is passed on: DNA and RNA Found in all food sources that are from animals and plants. (DNA and RNA)
Breakdown of nucleic acids: Mouth to Stomach Mechanical Digestion: Mastication Propulsion: Swallowing(Oropharynx)- bolus of food
Esophagus to Stomach -By peristalsis, bolus of food is propelled down through the esophagus towards the stomach.
Small Intestine • Most of nucleic acid digestion takes place within the small intestine • Nucleic acids are dissolved in gastric chyme which is deposited into the duodenum • Pancreatic juice, which contains nucleases, is released to initiate nucleic acid degradation
Nuclease- An enzyme that cleaves the chains in nucleotides in nucleic acids into smaller units.
Absorption • Nucleotides undergo further degradation in the microvilli of the small intestine • Enzymes phosphatase and nucleosidase into three constituent parts • Membrane transport proteins bring products across basolateral membrane into capillaries
Nucleotidase- A hydrolytic enzyme that catalyzes the hydrolysis of a nucleotide into a nucleoside and a phosphate.
Overview of Degradation Pt. 2 • The picture is a double stranded chromosome with 6 base pairs. Chromosomes are snipped apart by nucleases in the duodenum of the small intestine. These enzymes are secreted along with the pancreatic juice and differ depending on the type of nucleic acid the work on and the spot on the nucleic acid that they cut apart. Nucleases break apart the hydrogen bonds in the chromosome into individual nucleotides. In the brush border, nucleotides are then met by phosphotase, an enzyme which separates the phosphate from the molecule making it a nucleoside. The nucleoside is further degraded by nucleosidase which separates the pentose sugar from the nitrogenous base. Membrane transport proteins bring these components across the membrane and into capillaries of the small intestine.
-Made of 5 and 6 member nitrogen containing rings that are stuck together -Break down into uric acid. -Break down into ammonia, CO2, and beta-amino acids
Salvage pathways VS. De-novo synthesis -Free purine and pyrimidine bases are in large part salvaged and reused to make nucleotides from degradation of DNA and RNA. -They consume less energy than De-novo synthesis and is energetically the preferred source of nucleotides for nucleic synthesis. -Site: Cytosol of the liver, small intestine, and thymus - From small molecules, readily available in cells. -AA, ribose 5-phosphate, CO2, NH3
Allopurinol • The drug allopurinol is prescribed to individuals suffering from gout disease • It works by inhibiting the oxidation of xanthine, the precursor to uric acid • The regulation of uric acid is an effective way to inhibit gout proliferation.