文档介绍：Antiviral Drugs
沈阳药科大学药物化学
教研室
VIRUSES: Overview
Viruses are obligate intracellular parasites, which massively multiply by diverting or “hijacking” the host cell biosynthetic machinery.
Viruses were first defined as filterable infectious agents, based on their small size and ability to cause disease (In 1892, Dr. Iwanowski reported that filtered extracts of o leaves with mosaic disease could still infect other plants).
Viruses can range from the very small ~ 20 nm to the near bacterial – 200×200×250 nm for the pox viruses such as inia, first described by light microscopy by Dr. Buist in 1887.
All classes of anisms studied to date are the host to viruses.
VIRUSES: Overview
Viruses can have their own satellite viruses, which borrow proteins crucial for their multiplication from the “host” virus, . Hepatitis delta virus, which causes serious liver disease in humans already infected with Hepatitis B virus.
Viruses alone have very little capacity to produce anything – in the absence of the host they are usually entirely dormant (under some conditions are able to make small amounts of nucleic acid).
Viruses differ from bacteria and fungi, which are usually capable of growth in the absence of host cells of other species.
The virus life cycle
the process is initiated by binding of the virus to its particular cellular receptor.
The next step involves the delivery of the viral genome into the cell
The method of delivery as a sophisticated “molecular hypodermic syringe”(bacteriophage of E. coli) or a “molecular bomb”– goes off when the package is the appropriate partment.
The virus life cycle
Initiation phase
1. Attachment
2. ration
3. Uncoating
Replication phase
4. Gene expression
5. Genome replication
Release phase
6. Assembly
7. Maturation
8. Release.
VIRUSES: Structure and Properties
Viruses consist of particles containing a nucleic acid (RNA or DNA), which encodes all the information necessary for multiplication in the correct environ