BIOC 2300 Lecture Notes - Lecture 28: Nitrate Reductase, Nitrogen Fixation, Nitrogen Assimilation

• School: Dalhousie University
• Department: Biochem & Molecular Biology
• Course: BIOC 2300
• Professor: David Byers

Document Summary

Outline: nitrogen fixation and assimilation, reactions of amino groups: Amidation, transamination, oxidative amination: essential and non-essential amino acids, excretion of nitrogen as urea, urea cycle in liver, amino acids as energy substrates: Nitrogen: essential element found in amino acids, nucleotides, chlorophyll, nitrogenous bases, and many other organic molecules (organic nitrogen), 78% of atmosphere (n2) Mostly nitrates (no3-), nitrites (no2-), and ammonium salts (nh4+: animals can only use organic nitrogen, plants can utilize inorganic and organic nitrogen molecules, atmospheric n2 is the majority of nitrogen, but not available for plants or animals. Ammonium has no oxygen in its molecule thus, it is not an oxygen source. The nitrogen cycle balances the nitrogen on earth. Atmospheric nitrogen (inert gas) exists, but there is one enzymatic complex that can convert the nitrogen to ammonia/ammonium (interchangeable just a ph difference) through the process of fixation.