Question

Total number of amino acids in the capsid of TMV having 2130 capsomers is
A. 336540
B. 162622
C. 948
D. 387921

Answer 1

Hint: Tobacco mosaic virus (TMV) is found in all the parts of the plant except the few cells at the tip of the growing areas. TMV contains a protein ’capsid’ made up of capsomeres and it has 2130 capsomeres. Single-stranded RNA is the genetic material of the tobacco mosaic virus.

Complete answer: Tobacco mosaic virus (TMV) is positive-sense single-stranded RNA virus species in the genus tobacco virus that infects a wide range of plants especially tobacco and other numbers of the family Solanaceae that includes many species such as petunias, tomatoes and tobacco.
It has 2130 capsomeres. The protein capsomere units consist of 158 amino acids which are assembled into four main alpha-helices. So, the total number of amino acids is \[2130\times 158=336540\]. Tobacco mosaic virus (TMV) a widespread plant pathogen found in tobacco as well as in many other plants. It does not cause infection in humans or other animals. TMV infects tobacco and other closely related species like tomatoes. It is transmitted between plants by contact through plasma. It can be transmitted naturally or through the hands of farmers. It changes the colour of the leaves from green to yellow or white in a mosaic pattern since it infects the chloroplasts of the leaves of the plants.
Thus, the correct answer is option A.

Note: Tobacco mosaic virus (TMV) is a rod-shaped single-stranded virus that infects plants belonging to the family of Solanaceae. It is responsible for changing the colour of the vegetative parts of the infected plant such as leaves, from green to yellow or white in a mosaic pattern. This is because it infects the chloroplasts and hence the chlorophyll pigments.