Lipids + Carbohydrates Flashcards
The role of proteins in viruses
- Defence and targeting of the genome
- Shape of virion
- Enzymes for multiplication
- Receptors
Give the groupings of proteins of viruses
- Structural proteins
- Surface proteins
- Core proteins
- Non-structural proteins
Surface proteins
- Capsid/Envelope
- Characteristics:
- Shape
- Antigenicity
- Adsorption
- HA activity
- Enzymes for penetration/release of virions
Core proteins
- Characteristics:
- NA protection
- Stabilisation
- Enzymes for replication
Non-structural proteins
- Coded in the viral genome
- Not integrated in the virion
- Only present in the vegetative virus
- Early proteins
- Late proteins
Early proteins
- Regulation of the cell
- Inhibition of cellular defence
- Enzymes for replication
Late proteins
Enzymes for structural protein maturation + virus assembly
List the methods of protein investigation
- SDS-polyacrylamide-gel electrophoresis (PAGE)
- Immunoblotting
- Immunoperoxidase staining
- Monoclonal antibody production
SDS-Polyacrylamide-gel electrophoresis (PAGE)
- Concentrated virus suspension
- SDS + Mercapto-ethanol
- → Linearisation
- SDS + Mercapto-ethanol
- Electrophoresis
- Staining
- Polypeptide map
- Characteristic of the virus
- Number + size of viral polypeptides
Immunoblotting
- Western blot
- Transfer of viral proteins from PAGE → Nitrocellulose filter
Immunoperoxidase staining
SDS-PAGE, western blot or in histology sections
- Detection of antigens
- Diagnostics, identification
- Mechanism + timing of protein production
- Epitope investigation
Immunoperoxidase staining:
Steps of detection of antigens
- Cover with primary Ab
- Incubation + washing
- Cover with conjugate
- Incubation + washing
- Cover with substrate
- Colour reaction
Monoclonal antibody production steps
- Monoclonal antibody: produced by a single clone of B cells
- Specific for a particular epitope
- Mouse immunisation with viral antigen
- Isolation of lymphocytes from spleen
- Mixing with myeloma cells (Mitosis, no Ab production)
- Fusion of cells by polyethene glycol
Title the figure

Monoclonal antibody production

Immunised mice

Remove spleen

Cell fusion

Myolema cells

Expand cells in 48-well plates

Grow cells in HAT media

Check cells for production of antibodies

ELISA

Expand cells that tested positive into 96-well plates

Production of monoclonal antibodies in mice or tissue culture
Viral lipids
- Enveloped viruses (30-35%)
- Acquired from the cellular membrane structures
- Phospholipid, cholesterol
- Virus-specific glycoproteins
- Virus-specific lipids → Pox, African swine fever
Viral carbohydrates
- Ribose, deoxyribose
- in the NA
- Glycoproteins
- On the surface
- Pox: in the core too