CHAPTER 29: Virus structure, classification and antiviral therapy Flashcards
Give 5 Double-stranded DNA Viruses
Poxviruses Herpesviruses Adenoviruses Papoviruses Polyomaviruses
Give a Single-stranded DNA Virus
Parvoviruses
___________ may serve directly as mRNA and be translated into structural protein and an RNA-dependent RNA polymerase.
RNA sense (positive)
___________ contains an RNA-dependent RNA polymerase that transcribes the viral genome into mRNA.
RNA antisense (negative)
___________ have single-stranded sense RNA that cannot act as mRNA.
Retroviruses
Viral nucleic acid is covered by a protein coat of repeating units called __________
Capsids
The spherical capsid symmetry
Icosahedral
The capsid arranged around a rotational axis
Helical
With some viruses, the genome is completely released from the capsid during or after penetration. This is known as “__________”.
Uncoating
Drugs that prevent uncoating and release of RNA though resistance may occur readily.
Amantadine
Rimantidine
__________ inhibits uncoating of picornaviruses and is active against enteroviruses and rhinoviruses; it is absorbed orally and clinical trials suggest it shortens clinical symptoms.
Pleconaril
__________ is selectively converted into acyclo-guanosine monophosphate (acyclo-GMP) by viral enzymes, then into a potent inhibitor of viral DNA polymerase by host enzymes.
Aciclovir
The acyclo-GMP causes viral DNA ________.
Chain termination
Resistance to Aciclovir occurs through the development of deficient ___________ production
or alteration in the viral polymerase gene
Thymidine kinase
_________ inhibits the reverse transcriptase of hepatitis B and HIV.
Lamivudine
Give examples of nucleotide and nucleoside inhibitors developed as alternative treatments for hepatitis B
Adefovir Eentecavir Tenofovir Telbivudine Clevudine
___________ is a guanosine analogue that inhibits several steps in viral replication including capping and elongation of viral mRNA.
Ribavirin
Antiviral drug that is active against respiratory syncytial virus, influenza A and B, parainfluenza virus, Lassa fever, hantavirus and other arenaviruses.
Ribavirin
The longest established antiretroviral drug that is a Nucleoside Reverse Transcriptase Inhibitor
Zidovudine (AZT)
Antiviral drugs that inhibit reverse transcriptase directly
Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
A protease inhibitor that act against human rhinovirus 3C protease. It is administered by nasal spray and appears to have useful activity in rhinovirus infection.
Ruprintrivir
__________ including zanamivir and oseltamivir inhibit the final stage in the release of virus from the host cell.
Neuraminidase inhibitors
Antiretroviral agents developed to block the insertion of the HIV viral genome into the DNA of the host cell
Integrase inhibitor
