Question

Define these words

polyprotein

polyprotein cleavage sites

autocatalytic

4P mechanism

Lysis protein of QB and MS2

Virus “superfamily”

Omega sequence of TMV

VSR

Transcriptional attenuation

Answer 1

Polyproteins are the collection of some small proteins that are covalently conjoined. These type of protein is usually found in the virus genome. The small proteins that are a part of polyproteins will perform different biological functions.

Polyprotein cleavage sites are specific sites present or motif at which virus encoded proteases with cleave or cut the polyprotein to make many proteins with different biological function. These sites are dependent on the nature of virus and nature of polyproteins.

Autocatalytic is a chemical reaction in which product of the reaction is itself acting as a catalyst of the reaction. For example, pepsin enzyme activation from pepsinogen is an example of autocatalytic reaction.

4P stand for “Public-Private-Producers Partnerships”. This mechanism is focus on improving the sustainably the source of revenue of poor small holders with the help of elevation of private sector investments and access to markets.

MS2 is an icosahedral phage that encodes for four proteins. The fourth protein of MS2 is lysis protein (L protein), that is responsible for the lysis of the host. QB too is an icosahedral phage. Lysis protein of this phage is A2 protein.

Virus superfamily category of related virus of one or more families. Like double stranded dna virus family, single stranded DNA virus family.

5'-untranslated sequence of tobacco mosaic virus is known as omega sequence and also known as translational enhancer.

Vrs is also known as very short patch repair protein is bacteria like E. coli This protein act as a repair protein of DNA.

Transcriptional attenuation is mechanism in bacteria which premature termination of transcription is occur. Hence, in this condition, mRNA is not expressed.