Biomolecules and Enzymes

Glycerate 3-phosphate acts as a precursor for serine which in turn, can act as precursor to create cysteine and glycine through the homocysteine cycle.

Milk paint is a non-toxic water based mixture used as a paint. It is made from milk and lime with or without pigments added for colour. Borax is added in addition to lime in the milk paint recipe to assist the lime in dissolving casein and as a preservative.

Aniline Blue WS is a mixture of methyl blue and water blue. It may also be either one of them. Aniline blue or its constituents are used to stain collagen, as the fibre stain in Masson's trichrome.

EC 6.3 includes ligases used to form carbon-nitrogen bonds.

The ProDom database contains protein domain families generated from the SWISS-PROT database by automated sequence comparisons.

This option is correct because the Biological General Repository for Interaction Datasets (BioGRID) is a curated biological database of protein-protein and genetic interactions and STRING is a database of known and predicted protein interactions.

Peptidoglycan consists of sugar derivatives (N-acetylglucosamine and N-acetylmuramic acid) cross-linked by short peptide chains of amino acids. This mesh-like structure provides strength to bacterial cell walls.

Histidine has an imidazole ring which often sits inside the active site of an enzyme and helps bonds to be broken or made. It can do this because it can exist in two states -uncharged, or positively charged.

Isoleucine is similar to leucine and valine except that the orientation of the atoms in the sidechain is slightly different. Isoleucine also has two centres of asymmetry.It is an aliphatic amino acid.

Glutathione is a tripeptide that contains an unusual peptide linkage between the amine group of cysteine and the carboxyl group of the glutamate side-chain. It is an antioxidant, preventing damage to important cellular components caused by reactive oxygen species such as free radicals and peroxides.

Lysine, is an essential amino acid. Lysine is important for proper growth, and it plays an essential role in the production of carnitine, a nutrient responsible for converting fatty acids into energy and helping to lower cholesterol. It is a basic amino acid.

Glutamic acid is one of the 20 proteinogenic amino acids, and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salts of glutamic acid are known as glutamates.

Glycine is the simplest and smallest of all amino acids, and the only one which is not optically active since it has a single hydrogen atom as it's sidechain.

Methionine is a very special amino acid in that it is the start amino acid in the process of translation (protein synthesis. Methionine has a highly hydrophobic sidechain.

3,3'-Diaminobenzidine (DAB) is an organic compound. This derivative of benzidine is a precursor to polybenzimidazole fiber. As its water-soluble tetrahydrochloride, it has been used in immunohistochemical staining of nucleic acids and proteins.