Biomolecules and Enzymes

Ricin, from the castor oil plant Ricinus communis, is a highly toxic, naturally occurring protein. A dose as small as a few grains of salt can kill an adult.

Ependymin is a glycoprotein associated with the consolidation of long-term memory, claims involving protection from strokes and neuronal regeneration.

Pikachurin is a polysaccharide that in humans is encoded by the EGFLAM gene.Pikachurin is a dystroglycan-interacting polysaccharide which has an essential role in the precise interactions between the photoreceptor ribbon synapse and the bipolar dendrites.

Keratin refers to a family of fibrous structural proteins. Keratin is the key structural material making up the outer layer of human skin. It is also the key structural component of hair and nails.

A peptide bond (amide bond) is a covalent chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, causing the release of a molecule of water (H2O), hence the process is a dehydration synthesis reaction (also known as a condensation reaction), and usually occurs between amino acids.

Salt bond fall into the broader category of noncovalent interactions. A salt bond is actually a combination of two noncovalent interactions: hydrogen bonding and electrostatic interactions .This is most commonly observed to contribute stability to the entropically unfavourable folded conformation of proteins.

Reverse transcriptase is responsible for the multiplication of human immuno virus in WBC of host .

Ribozyme is not a protein enzyme.These are RNA, capable of catalytic activity.

Immunoglobulins can be divided into five different classes based on differences in the amino acid sequences in the constant region of the heavy chains. They are IgD, IgM, IgE, IgA and IgG.

Alkaline protease is derived from Bacillus licheniformis.

This statement is true because at isoelectric point, an α-amino acid has the minimum solubility.

This option is correct,  because antibodies are formed in the body only on demand, adenine, guanine and cytocine are found in all DNA and RNA molecules and the milk protein casein has phosphate groups as prosthetic groups.

Enzymes responsible for peptide generation in MHC-I pathway are cytosolic proteosomes.

This option is correct because Rubredoxin is a small iron-sulphur protein found in various sulphur-metabolizing bacteria, Rieske proteins are iron-sulphur protein components of cytochrome bc1 complexes and cytochrome b6f complexes which were first discovered and isolated by John S. Rieske and co-workers in 1964 and Aconitase is an iron-sulphur protein that catalyses the interconversion of citrate and isocitrate

Selenium is an important constituent of the enzyme glutathione peroxidase, which is responsible for destroying lipid-damaging peroxides.