Question

7.write a note on i) molybdenum enzymes ii) vit B12

8. comment on ferrin and transferrins

Answer 1

1) Molybdenum enzymes are described as ubiquitous because they have been isolated from organisms throughout the entire kingdom of life, from simple bacteria to humans. Conservation of the molybdenum enzymes through a billion years of evolution underscores their importance to the health of evolving organisms. It is now believed that the molybdenum enzymes are the chemical descendants of tungsten enzymes. This hypothesis is based on the discovery of tungsten enzymes in archaebacteria, the most ancient organisms, where these tungsten enzymes have structures and functions very similar to those of the molybdenum enzymes found in higher organisms, including humans. The selection of tungsten over molybdenum by the archaebacteria is, in hindsight, consistent with the biogeochemistry of the anaerobic prehistoric environment.
Molybdenum is an essential trace element for all higher organisms where molybdenum enzymes have a number of important roles in the health of these organisms. Molybdenum in nitrate reductase is required by all plants for proper nitrogen assimilation. Molybdenum in xanthine oxidase, sulfite oxidase and aldehyde oxidase is the functional center for these enzymes involved in the human diseases of gout, combined oxidase deficiency and radical damage following cardiac failure. Combined oxidase deficiency is a rare genetic disease responsible for such severe neurological disorder that infant children with this defect rarely survive. As a consequence of research directed at understanding the basis for this fatal disease, the tools of molecular biology and genetics have uncovered a link between one of the many proteins required to synthesize the molybdenum cofactor of these enzymes and a protein used in neuronal synapses. This illustrates how the biological impact of the molybdenum enzymes may reach beyond the limited context of their unique catalytic function.

2)

Vitamin B12, also known as cobalamin, is an important water-soluble vitamin.

It plays an essential role in the production of your red blood cells and DNA, as well as the proper functioning of your nervous system.

Vitamin B12 is naturally found in animal foods, including meats, fish, poultry, eggs and dairy. However, it can also be found in products fortified with B12, such as some varieties of bread and plant-based milk.

3)

Ferritin is stored in the body’s cells until it’s time to make more red blood cells. The body will signal the cells to release ferritin. The ferritin then binds to another substance called transferrin.

Transferrin is a protein that combines with ferritin to transport it to where new red blood cells are made. Imagine transferrin as a dedicated taxi for iron.

While it’s important for a person to have normal iron levels, having enough stored iron is important too. If a person doesn’t have enough ferritin, iron stores can deplete quickly.