The conventional method for naming the restriction enzymes is followed. In case of EcoRI, the R indicates

Options

A. genus
B. species
C. strain
D. narne of the scientist

Answer

To answer the question regarding what the "R" in EcoRI indicates, we can break down the naming convention of restriction enzymes step by step:

### Step-by-Step Solution:

1. **Understanding the Naming Convention**: The naming of restriction enzymes follows a specific convention where each part of the name provides information about the enzyme's origin.

2. **First Letter**: The first letter of the name (in this case, "E") represents the genus of the bacterium from which the enzyme is derived. For EcoRI, it refers to the genus *Escherichia*.

3. **Next Two Letters**: The next two letters (in this case, "co") represent the species of the bacterium. For EcoRI, it refers to *coli*, making the full name refer to *Escherichia coli*.

4. **The "R" in EcoRI**: The letter "R" specifically indicates the strain of the bacterium. In this context, it signifies that the enzyme is derived from a particular strain of *Escherichia coli*.

5. **Roman Numeral**: The Roman numeral "I" at the end of EcoRI indicates that this is the first restriction enzyme isolated from that strain.

6. **Conclusion**: Therefore, the "R" in EcoRI indicates the strain of the bacterium from which the restriction enzyme is derived.

### Final Answer:
The "R" in EcoRI indicates the strain of the bacterium.

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