Search results
Results from the WOW.Com Content Network
Nitrogen is a fundamental chemical component of amino acids, the molecular building blocks of protein. As such, nitrogen balance may be used as an index of protein metabolism. [1] When more nitrogen is gained than lost by an individual, they are considered to have a positive nitrogen balance and be in a state of overall protein anabolism.
The stable isotope composition of amino acids refers to the abundance of heavy and light non-radioactive isotopes of carbon (13 C and 12 C), nitrogen (15 N and 14 N), and other elements within these molecules. Amino acids are the building blocks of proteins.
Carbon is found in all organic molecules, whereas nitrogen is an important component of nucleic acids and proteins. Phosphorus is used to make nucleic acids and the phospholipids that comprise biological membranes. Sulfur is critical to the three-dimensional shape of proteins. The cycling of these elements is interconnected.
nitrogen: 7: 5: Ubiquitous, essential for all forms of life; all proteins and nucleic acids contain substantial amounts of nitrogen. [11] Toxic in some forms. [11] osmium: 76: 1a: None known. [11] Osmium is very rare, substantially more so than any element essential to life. [3] The oxide is toxic to humans. [11] oxygen: 8: 5
The six aforementioned elements are used by organisms in a variety of ways. Hydrogen and oxygen are found in water and organic molecules, both of which are essential to life. Carbon is found in all organic molecules, whereas nitrogen is an important component of nucleic acids and proteins.
Found in carbohydrates, lipids, nucleic acids, and proteins. Hydrogen 10% 10% Found in water, carbohydrates, lipids, nucleic acids, and proteins. Nitrogen 1% 4% Found in nucleic acids, proteins, some lipids (e.g. sphingolipids) and some polysaccharides (e.g. chitin) Oxygen 77% 63% Found in water, carbohydrates, lipids, nucleic acids, and proteins.
The nif genes are genes encoding enzymes involved in the fixation of atmospheric nitrogen into a form of nitrogen available to living organisms. The primary enzyme encoded by the nif genes is the nitrogenase complex which is in charge of converting atmospheric nitrogen (N 2) to other nitrogen forms such as ammonia which the organism can use for various purposes.
The nitrogen cycle is an important process in the ocean as well. While the overall cycle is similar, there are different players [40] and modes of transfer for nitrogen in the ocean. Nitrogen enters the water through the precipitation, runoff, or as N 2 from the atmosphere. Nitrogen cannot be utilized by phytoplankton as N