Search results
Results from the WOW.Com Content Network
Tyrosine ball and stick model spinning. L-Tyrosine or tyrosine (symbol Tyr or Y) [2] or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a conditionally essential amino acid with a polar side group.
The yellow colour is due to xanthoproteic acid which is formed due to nitration of certain amino acids, most common examples being tyrosine and tryptophan. [1] This chemical reaction is a qualitative test, determining the presence or absence of proteins. Reaction of nitration of tyrosine as an example of the xanthoproteic reaction
The increase of absorbance at 595 nm is proportional to the amount of bound dye, and thus to the amount (concentration) of protein present in the sample. [ 6 ] Unlike other protein assays, the Bradford protein assay is less susceptible to interference by various chemical compounds such as sodium, potassium or even carbohydrates like sucrose ...
For premium support please call: 800-290-4726 more ways to reach us
The reagent is made by dissolving metallic mercury in nitric acid and diluting with water, forming mercuric nitrate (Hg[NO 3] 2). [3] In the test, the phenol group in the side chain of tyrosine gets nitrated, and that product then complexes with Hg(I) or Hg(II) ions to give a red colored precipitate.
From the titration of protonatable group, one can read the so-called pK a 1 ⁄ 2 which is equal to the pH value where the group is half-protonated (i.e. when 50% such groups would be protonated). The pK a 1 ⁄ 2 is equal to the Henderson–Hasselbalch pK a (pK HH a) if the titration curve follows the Henderson–Hasselbalch equation. [14]
The ocean contains a natural buffer system to maintain a pH between 8.1 and 8.3. [11] The oceans buffer system is known as the carbonate buffer system. [ 12 ] The carbonate buffer system is a series of reactions that uses carbonate as a buffer to convert C O 2 {\displaystyle \mathrm {CO_{2}} } into bicarbonate . [ 12 ]
In chemistry, the biuret test (IPA: / ˌ b aɪ j ə ˈ r ɛ t /, / ˈ b aɪ j ə ˌ r ɛ t / [1]), also known as Piotrowski's test, is a chemical test used for detecting the presence of at least two peptide bonds in a molecule. In the presence of peptides, a copper(II) ion forms mauve-colored coordination complexes in an alkaline solution.