What do nucleoside analogs do?
The nucleoside analogues resemble naturally occurring nucleosides and act by causing termination of the nascent DNA chain. These agents are generally safe and well tolerated as they are used by the viral, but not human polymerases in DNA replication.
What do nucleoside analogs inhibit?
Nucleoside antibiotics are a class of antibiotics that inhibit the MraY enzyme (phospho-N-acetylmuramoyl-pentapeptide translocase) in peptidoglycan biosynthesis pathway of mycobacteria, gram positive and gram negative strains.
What is a pyrimidine nucleoside?
The pyrimidine nucleosides, cytidine and deoxycytidine, are the intermediate products of the degradation of ribonucleic acid, deoxyribonucleic acid, and cytosine nucleotides. They occur free in organisms in very low concentrations.
What is an example of a nucleoside analog?
Actually, nucleoside analogues are a large class of agents that include drugs for cancer (cytarabine, gemcitabine, mercaptopurine, azacytidine, cladribine, decitabine, fluorouracil, floxuridine, fludarabine, nelarabine), and rheumatologic diseases (azathioprine, allopurinol) and even bacterial infections (trimethoprim) …
What are structural analogs of nucleotides?
Structurally, nucleotide analogs are acyclic nucleoside phosphonates (nucleoside monophosphates) that are designed to circumvent the first phosphorylation step necessary for the activation of nucleoside analogs, such as zidovudine, stavudine, didanosine, lamivudine, and abacavir (1.
How can nucleoside analogues affect viral reproduction?
During DNA/RNA replication, nucleoside analogs are incorporated into nascent DNA or RNA chains resulting in termination of nucleic acid synthesis or in accumulation of mutations in viral genomes to suppress viral replication due to error catastrophe.
How many rings does a pyrimidine have?
The pyrimidines, cytosine and thymine are smaller structures with a single ring, while the purines, adenine and guanine, are larger and have a two-ring structure. E. The purines, adenine and cytosine, are large with two rings, while the pyrimidines, thymine and uracil, are small with one ring.
Is AZT an example of nucleoside analogues?
Nucleoside analogue reverse transcriptase inhibitors including didanosine (ddI), lamivudine (3TC), stavudine (d4T), zalcitabine (ddC), and zidovudine (ZDV, formerly AZT) are used to treat human immunodeficiency virus (HIV) infection.
How do nucleotide analogs affect base pairing?
Base Analogues Since 5-bromouracil can pair with either adenine or guanine, it also affects base pairing during DNA replication, which leads to mutations. An analogue of adenine, 2-aminopurine, also causes mutations in a similar way since it can pair with either T or C.
How does acyclovir and other DNA analogs act to inhibit the replication of an RNA virus?
Antiherpesvirus drugs Drugs that are effective against herpesviruses interfere with DNA replication. The nucleoside analogs (acyclovir and ganciclovir) actually mimic the normal nucleoside and block the viral DNA polymerase enzyme, which is important in the formation of DNA.
What is the function of guanine and cytosine?
Within the DNA molecule, guanine bases located on one strand form chemical bonds with cytosine bases on the opposite strand. The sequence of four DNA bases encodes the cell’s genetic instructions.