Explain structure of some important viruses in detail like TMV and bacteriophages T2.
Explain structure of some important viruses in detail like TMV and bacteriophages T2.
STRUTURE OF TMV:The structure of tobacco mosaic virus is impossible to see with the human eye because it is very small - approximately 300 nanometers long. This means that 3,000 tiny viruses would fit in a single millimeter.
The basic makeup of all viruses is pretty much the same. First, they all contain a genome, which carries their genetic blueprint. Of course, we humans have a genome too, but ours is the recipe for making a human, and a virus' genome is the recipe for making a virus.
Tobacco mosaic virus' genome is different from ours in other ways, too. Humans have a genome made from a molecule called DNA, but tobacco mosaic virus' genome is made from DNA's cousin, a molecule called RNA. The human genome is also split into many chunks called chromosomes. However, tobacco mosaic virus has a genome that is attached together in one strand.
The second thing all viruses need is a capsid, or a container to hold and protect their genome. Tobacco mosaic virus has a helical-shaped capsid made of more than 2,000 copies of a particular protein. Imagine 2,000 beads on a string that loops around and around like a tight spiral staircase. The tube-like structure that is formed is similar to tobacco mosaic virus' helical capsid.
So, in a nutshell (which is actually quite like a capsid!) the structure of tobacco mosaic virus is an RNA genome inside a helical capsid. BSCTERIORIOPHAGES:Bacteriophages attacking Escherichia coli are called coliphages or T-phages. Max Delbruck (1938) numbered coliphages as T-even phages (T2, T4, T6 etc.) and T-odd phages (T1, T3, T5 etc.).
1. Structure: The virion of T-even phage is binal or tadpole like structure with a polyhedral head connected to a helical tail through a short collar. The head composed of about 2000 capsomeres arid encloses a tightly packed dsDNA (50 nm long). The tail has an inner hollow tube called core, surrounded by a contractile sheath which consists of 24 annular rings. The distal end of the tube is connected to a hexagonal basal plate with spike or tail spin at each corner. Six long, flexible tail fibers also arise from the basal plate which helps in adsorption to bacteria
STRUTURE OF TMV:The structure of tobacco mosaic virus is impossible to see with the human eye because it is very small - approximately 300 nanometers long. This means that 3,000 tiny viruses would fit in a single millimeter.
The basic makeup of all viruses is pretty much the same. First, they all contain a genome, which carries their genetic blueprint. Of course, we humans have a genome too, but ours is the recipe for making a human, and a virus' genome is the recipe for making a virus.
Tobacco mosaic virus' genome is different from ours in other ways, too. Humans have a genome made from a molecule called DNA, but tobacco mosaic virus' genome is made from DNA's cousin, a molecule called RNA. The human genome is also split into many chunks called chromosomes. However, tobacco mosaic virus has a genome that is attached together in one strand.
The second thing all viruses need is a capsid, or a container to hold and protect their genome. Tobacco mosaic virus has a helical-shaped capsid made of more than 2,000 copies of a particular protein. Imagine 2,000 beads on a string that loops around and around like a tight spiral staircase. The tube-like structure that is formed is similar to tobacco mosaic virus' helical capsid.
So, in a nutshell (which is actually quite like a capsid!) the structure of tobacco mosaic virus is an RNA genome inside a helical capsid. BSCTERIORIOPHAGES:Bacteriophages attacking Escherichia coli are called coliphages or T-phages. Max Delbruck (1938) numbered coliphages as T-even phages (T2, T4, T6 etc.) and T-odd phages (T1, T3, T5 etc.).
1. Structure: The virion of T-even phage is binal or tadpole like structure with a polyhedral head connected to a helical tail through a short collar. The head composed of about 2000 capsomeres arid encloses a tightly packed dsDNA (50 nm long). The tail has an inner hollow tube called core, surrounded by a contractile sheath which consists of 24 annular rings. The distal end of the tube is connected to a hexagonal basal plate with spike or tail spin at each corner. Six long, flexible tail fibers also arise from the basal plate which helps in adsorption to bacteria
