Nucleic Acid Chemistry PDF Slides

Nucleic Acid Chemistry Dr Kapila Raina Assistant Professor, Department Of Biochemistry Nucleic Acids are present in all living organisms. Nucleic Acids are those substances which are present in the nucleus and showing acidic properties. Genetic information is present in most of...

Nucleic Acid Chemistry Dr Kapila Raina Assistant Professor, Department Of Biochemistry Nucleic Acids are present in all living organisms. Nucleic Acids are those substances which are present in the nucleus and showing acidic properties. Genetic information is present in most of the organisms in DNA and in some virus in RNA. Nucleic Acid store information and transmit information from a parent cell to daughter cells. This information is used to synthesis proteins. Nucleic Acids are polymers of specific sequence of subunits or monomers are called nucleotides. Nitrogenous base (N base):- N bases are of two types i.e. Purines and Pyrimidine. All nitrogenous base of nucleic acids are derived from two heterocyclic bases purine and pyrimidine. Purines are Adenine and Guanine. Pyrimidine are cytosine, uracil and thymine. Functions of Nucleotides  Some Important Nucleotides Adenine derivatives Guanine derivatives Cytosine derivatives Uracil derivatives Hypoxanthine derivatives Vitamin derivatives Synthetic derivatives  Cyclic AMP (cAMP) It is a major metabolic regulator. It mediates the action of several hormones at the cellular level. Adenylate cyclase of cell membrane being activated by the hormone epinephrine, norepinephrine and glucagon from cAMP from ATP. Thyroid hormones may increases the synthesis of adenylates cyclase. It is destroyed in tissues by its conversions to AMP by the enzyme phosphodiesterase. The intracellular cAMP concentrations are near 1 micromole.  Functions of cAMP In the lungs it is involved in the regulation of many functions related to inflammatory cells. It supresses immune and inflammatory cell activity. Deoxyribo Nucleic Acid (DNA)  Ribonucleic acid (RNA) RNA is also a polymer of mononucleotides. The bonds between the mononucleotides are similar to those in DNA, are polynucleotides, linked by phoshodiester bonds. However, RNA differ from DNA in some ways. They are much smaller in size and are mostly single stranded. The sugar they contain is ribose instead of 2-deoxyribose of DNA. They contain a pyrimidine base; Uracil, instead of thymine of DNA. Their major role in gene expression, in contrast to DNA which stores genetic information.  Role of RNA:- RNA plays multiple roles. It serves as genetic material for some viruses ( e.g. tobacco mosaic virus, poliovirus and influenza virus). It carries genetic information to the site of protein synthesis via mRNA. tRNA forms the link between mRNA and amino acids which help in protein synthesis. It is an essential component of ribosomes (rRNA). Some RNAs also have enzymatic activity and act as ribozymes. Thank you