Sullivan and McCarthy’s Test Definition Sullivan and McCarthy’s test is a biochemical test for the detection of the amino acid methionine or methionine-containing proteins. The test is a specific test for methionine which has a high degree of specificity towards methionine as it gives negative results with all other amino acids. The test, however, gives a positive result with glycylmethionine. …
Solubility Tests of Proteins Definition Solubility tests are tests performed to determine the ability of compounds to dissolve in a solvent, which is usually a liquid. These tests are essential to determine the size and polarity of unknown compounds and the presence of acidic and basic functional groups. Solubility tests for proteins and amino acids are qualitative tests that determine …
Nitroprusside Test Definition Nitroprusside test is a biochemical test used for the detection of the free –SH groups in amino acids or the cysteine amino acid in a protein. The test is a specific test for cysteine as it is the only amino acid with a free –SH group in the structure. The test, however, is not specific to proteins …
Millon’s Test Definition Millon’s test is an analytical test used for the detection of the amino acid tyrosine, which is the only amino acid containing the phenol group. Millon’s test is a specific test for tyrosine, but it is not a specific test for protein as it also detects the phenolic group present in other compounds as well. Therefore, while …
Acree-Rosenheim test definition Acree-Rosenheim Test is a biochemical test used for the detection of tryptophan molecules in a protein sample. Acree-Rosenheim test is one of the essential tests for the confirmation of formaldehyde in the milk as milk vendors use formaldehyde as a preservative. This test thus helps to understand the condition of the milk sample so as to determine …
Ninhydrin Test Definition Ninhydrin test is a chemical test performed to detect the presence of ammonia, primary/secondary amines, or amino acids. This test involves the addition of ninhydrin reagent to the test sample that results in the formation of deep blue color, often termed as Ruhemann’s purple, in the presence of an amino group. Objectives of Ninhydrin Test To detect …
What is a peptide? A peptide is a short-chain made up of amino acid which, together with other peptides, forms a protein. The number of amino acids in a peptide can range from two amino acids to fifty amino acids. Based on the number of amino acids present in the peptide, peptides are of many types; peptides with ten or …
Amino acids constitute a group of neutral products clearly distinguished from other natural compounds chemically, mainly because of their ampholytic properties, and biochemically, mainly because of their role as protein constituents. An amino acid is a carboxylic acid-containing an aliphatic primary amino group in the α position to the carboxyl group and with a characteristic stereochemistry. Proteins are biosynthesized from …