Viruses and Prions book

Flashcards covering Viruses and Prions lecture notes.

Prions

Tiny pieces of folded protein that either can be acquired in the same manner as infectious agents or can spontaneously arise through mutations in a normal brain protein.

Oligonucleotide

A string of synthetic RNA nucleotides that seems to bind to the misshapen proteins and put them out of commission as a possible treatment for prion diseases.

Viruses

A unique group of biological entities that are known to infect every type of cell, including bacteria, algae, fungi, protozoa, plants, and animals.

Active or Inactive

It is best to describe viruses as either or __ (rather than alive or dead).

Bacteriophages

Viruses that infect bacteria.

Virome

The sum total of the viruses associated with your body.

Capsid

The protein shell that surrounds the nucleic acid in the central core of a virus.

Nucleocapsid

The capsid and the nucleic acid together.

Envelope

An additional covering external to the capsid, which is usually a modified piece of the host’s cell membrane.

Naked Viruses

Viruses that consist of only a nucleocapsid.

Spikes

Proteins on the outer surfaces of viruses that project from either the nucleocapsid or the envelope that allow viruses to dock with their host cells.

Virion

A fully formed virus that is able to establish an infection in a host cell.

Capsomeres

Identical subunits that are made up of protein molecules that each capsid is constructed from.

Helical and Icosahedral

The two different types of capsids for animal viruses.

Icosahedron

A three-dimensional, 20-sided figure with 12 evenly spaced corners.

Genome

The sum total of the genetic information carried by any organism

Positive-sense RNA

Single-stranded RNA genomes that are ready for immediate translation into proteins.

Negative-sense RNA

RNA genomes that have to be converted into the proper form to be made into proteins.

Retrovirus

A special type of RNA virus.

Host Range

The limitation on the range of hosts a virus can infect in a natural setting.

Tropisms

Tissue specificities for certain cells in the body.

Cytopathic Effects (CPEs)

Virus-induced damage to the cell that alters its microscopic appearance

Inclusion Bodies

Compacted masses of viruses or damaged cell organelles, in the nucleus and cytoplasm.

Syncytia

Fusion of multiple host cells into single large cells containing multiple nuclei.

Persistent Infections

A carrier relationship, in which the cell harbors the virus and is not immediately lysed.

Provirus

When viral DNA is incorporated into the DNA of the host.

Oncoviruses

Viruses that enter their host cell and permanently alter its genetic material, which can lead to cancer.

Lysogenic Conversion

When a bacterium acquires a new trait from its temperate phage.

In Vivo Methods

Methods that use living embryos or animals to cultivate viruses.

In Vitro Methods

Methods that use cells or tissues that are cultivated in the lab to cultivate viruses.

Plaques

Areas where virus-infected cells have been destroyed shown up as clear patches in the cell sheet when detecting the growth of a virus in culture.

Prions

Unusual forms even smaller and simpler than viruses, implicated in chronic, persistent diseases in humans and animals.

Spongiform Encephalopathies

Chronic, persistent diseases in humans and animals that are associated with prions.

Prions

Tiny pieces of folded protein that either can be acquired in the same manner as infectious agents or can spontaneously arise through mutations in a normal brain protein.

Oligonucleotide

A string of synthetic RNA nucleotides that seems to bind to the misshapen proteins and put them out of commission as a possible treatment for prion diseases.

Viruses

A unique group of biological entities that are known to infect every type of cell, including bacteria, algae, fungi, protozoa, plants, and animals.

Active or Inactive

It is best to describe viruses as either **** or ****__ (rather than alive or dead).

Bacteriophages

Viruses that infect bacteria.

Virome

The sum total of the viruses associated with your body.

Capsid

The protein shell that surrounds the nucleic acid in the central core of a virus.

Nucleocapsid

The capsid and the nucleic acid together.

Envelope

An additional covering external to the capsid, which is usually a modified piece of the host’s cell membrane.

Naked Viruses

Viruses that consist of only a nucleocapsid.

Spikes

Proteins on the outer surfaces of viruses that project from either the nucleocapsid or the envelope that allow viruses to dock with their host cells.

Virion

A fully formed virus that is able to establish an infection in a host cell.

Capsomeres

Identical subunits that are made up of protein molecules that each capsid is constructed from.

Helical and Icosahedral

The two different types of capsids for animal viruses.

Icosahedron

A three-dimensional, 20-sided figure with 12 evenly spaced corners.

Genome

The sum total of the genetic information carried by any organism

Positive-sense RNA

Single-stranded RNA genomes that are ready for immediate translation into proteins.

Negative-sense RNA

RNA genomes that have to be converted into the proper form to be made into proteins.

Retrovirus

A special type of RNA virus.

Host Range

The limitation on the range of hosts a virus can infect in a natural setting.

Tropisms

Tissue specificities for certain cells in the body.

Cytopathic Effects (CPEs)

Virus-induced damage to the cell that alters its microscopic appearance

Inclusion Bodies

Compacted masses of viruses or damaged cell organelles, in the nucleus and cytoplasm.

Syncytia

Fusion of multiple host cells into single large cells containing multiple nuclei.

Persistent Infections

A carrier relationship, in which the cell harbors the virus and is not immediately lysed.

Provirus

When viral DNA is incorporated into the DNA of the host.

Oncoviruses

Viruses that enter their host cell and permanently alter its genetic material, which can lead to cancer.

Lysogenic Conversion

When a bacterium acquires a new trait from its temperate phage.

In Vivo Methods

Methods that use living embryos or animals to cultivate viruses.

In Vitro Methods

Methods that use cells or tissues that are cultivated in the lab to cultivate viruses.

Plaques

Areas where virus-infected cells have been destroyed shown up as clear patches in the cell sheet when detecting the growth of a virus in culture.

Prions

Unusual forms even smaller and simpler than viruses, implicated in chronic, persistent diseases in humans and animals.

Spongiform Encephalopathies

Chronic, persistent diseases in humans and animals that are associated with prions.

What is the main characteristic of prions that make them different from viruses and bacteria?

A single infectious agent is composed of only protein.

What are some examples of diseases caused by prions?

Creutzfeldt-Jakob disease (CJD), Bovine Spongiform Encephalopathy (BSE, or 'mad cow disease')

What is the unique feature that distinguishes viruses from other microbes?

They lack a protein capsid and consist only of nucleic acid (either RNA or DNA).

What are the basic steps in the viral replication cycle?

Attachment, Penetration, Replication, Assembly, Release