M2M Exam 1 Drugs Flashcards
How do drugs such as DDI (dideoxyinosine) and nucleoside drugs like AZT (Azidothymine) inhibit DNA synthesis in HIV by reverse transcriptase?
These act as nucleoside analogs due to their similar chemical structure to nucleotides, but they lack the 3’-OH group. This terminated polimerization by nucleic acid polymerases such as HIV reverse transcriptase.
What is the function of Cisplatin?
Cisplatin is an alkylating agent used as a chemotherapeutic to damage DNA of cancer cells, by preventing proper DNA replication/transcription and thus cell growth.
Actinomycin D
This is a naturally occuring antibiotic that is used in chemotherapy. It functions by “intercalating” into DNA by inserting a its ring structure into DNA bases to alter the double-helical structure. it interferes bith BOTH DNA replication and transcription.
How is Doxorubicin (Adriamycin) similar to Actinomycin D?
It is also an intercalator to DNA, but it only interferes with DNA replication.
What is the function of Etoposide and Camptothecin?
These are chemotherapeutic agents that target topoisomerases that relax DNA supercoiling. Topoisomerases are necessary during DNA replication to avoid supercoiling as the double helix is opened up to copy the strands. Thus, these drugs allow the DNA breaks to remain and affect DNA structure and stop replication.
What is the function of Puromycin?
This is an antibiotic that mimics the acceptor 3’ end of tRNA that is charged with an AA. Puromycin is a nucleotide analogue that mimics the tRNA acceptor region, allowing peptide transfer and t_ermination of translation_t.
It functions by binding to the ribosome as it is translating and covalently attaching to the growing polypeptide chain, which prevents the completion of translation.
Acyclovir
This is a guanine nucleoside that lacks the cyclic sugar, which is selectively phosphorylated by viral thymidine kinases and selectively incorporated into DNA by viral DNA polymerases. It terminates further extension of the DNA strand.
Works for:
- Herpes Simplex Virus 1 and 2 infections
- Varicella Zoster Virus infection.
Quinolones
They inhibit DNA Gyrase, a topoisomerase found in most prokaryotes.
What is the function of Tamoxifen?
Tamoxifen antagonizes estrogen by binding to ER and preventing recruitment of HAT co-factors.
What is a broad spectrum antibiotic that binds bacterial RNA polymerase and blocks the RNA exit channel.
Rifampicin
What is Bartezomib?
Bartezomib is a proteosome inhibitor used to treart multiple myeloma. How? Well, since cancer cells produce a lot of protein, blocking the proteosome will lead to protein accumulation and destruction of cancerous cells.
