Search results
Results from the WOW.Com Content Network
The Hopkins-Cole reaction, also known as the glyoxylic acid reaction, is a chemical test used for detecting the presence of tryptophan in proteins. [1] A protein solution is mixed with Hopkins Cole reagent, which consists of glyoxylic acid. Concentrated sulfuric acid is slowly added to form two layers. A purple ring appears between the two ...
Glyoxylic acid is one of several ketone- and aldehyde-containing carboxylic acids that together are abundant in secondary organic aerosols. In the presence of water and sunlight, glyoxylic acid can undergo photochemical oxidation. Several different reaction pathways can ensue, leading to various other carboxylic acid and aldehyde products.
It is a spontaneous reaction and a type of post-translational modification of proteins meaning it alters their structure and biological activity. It is the covalent attachment between the carbonil group of a reducing sugar (mainly glucose and fructose) and the amino acid side chain of the protein. In this process the intervention of an enzyme ...
The reaction relies on the interaction between glyoxylic acid and the indole ring of the amino acid tryptophan, a structural feature found in most proteins. When proteins are exposed to concentrated sulfuric acid and glyoxylic acid, the indole group undergoes a reaction that produces a highly colored compound.
The different types of lipid-linked oligosaccharide (LLO) precursor produced in different organisms.. N-linked glycosylation is the attachment of an oligosaccharide, a carbohydrate consisting of several sugar molecules, sometimes also referred to as glycan, to a nitrogen atom (the amide nitrogen of an asparagine (Asn) residue of a protein), in a process called N-glycosylation, studied in ...
This acetate, bound to the active thiol group of coenzyme A, enters the citric acid cycle (TCA cycle) where it is fully oxidized to carbon dioxide. This pathway thus allows cells to obtain energy from fat. To use acetate from fat for biosynthesis of carbohydrates, the glyoxylate cycle, whose initial reactions are identical to the TCA cycle, is ...
These glycans link themselves to specific areas of the protein amino acid chain. The two most common linkages in glycoproteins are N-linked and O-linked glycoproteins. [3] An N-linked glycoprotein has glycan bonds to the nitrogen containing an asparagine amino acid within the protein sequence. [4]
O-fucosylation on EGF domains occurs between the second and third conserved cysteine residues in the protein sequence. [1] Once the core O-fucose has been added, it is often elongated by addition of GlcNAc, galactose and sialic acid. Notch is an important protein in development, with several EGF domains that are O-fucosylated. [24]