Question

1.

A) Nitrogen metabolism brings together a lot of different chemical entities within the many pathways covered in in order to generate the chemical transformations that are needed. Please list 5 chemical entities (that we have not described within these questions) and the general type of chemical transformation(s) they are needed for.

B)

The synthesis of the purine ring as part of a nucleotide monophosphate is astounding from the multiple sources accounting for the individual atoms in the two rings. Now the questions: How are the levels of AMP and GMP regulated? And why is this important from the point-of-view of the energetics of the cell?

Answer 1

1.A. Nitrogen metabolism: In an ecosystem, nitrogen is found very less in content in soil and both plants and animals compete for this nitrogen. Major part of nitrogen metabolism is the nitrogen cycle. Three main pools of nitrogen are soil, atmosphere and biomass.

Phosphorous absorbed as phosphate ions required for phosphorylation reaction.

Potassium absorbed as potassium ions required to maintain anion-cation balance and maintains cell turgidity.

Calcium absorbed as calcium ions required during mitotic spindle formation, required for normal functioning of cell membranes.

Sulphur absorbed as sulphates main constituents of several coenzymes, ferredoxin and vitamins (Biotin and Thyamine).

Manganese as manganous ions used in splitting of water to release oxygen during photosynthesis.

Chlorine as chloride anion helps to determine solute concentration and anion-cation balance in cells, essential in spliting water during oxygen intake and also during photosynthesis.

1.B. Nucleotides are forming important constituents in the majority of biochemical activites. They also act in metabolic regulation as it is the key response of intermediate response to the effective regulations such as AMP, ATP and ADP. Further cyclic derivatives of purine metabolism like cAMP and cGMP and have no other role in the process of metabolism rather than regulation.

The products of de novo purine biosynthesis are the nucleoside monophosphates AMP and GMP. These nucleosides can be readily converted by successive phosphorylation reactions into their metabolic triphosphate forms such as ATP and GTP which in turn provides energy to the cells.