Translocase is an enzyme required for

Options

A. DNA replication
B. RNA synthesis
C. initiation of protein synthesis
D. protein synthesis chain elongation

Explanation

To solve the question "Translocase is an enzyme required for," we will analyze each of the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Options**:
- The question provides four options regarding the function of translocase:
1. DNA replication
2. RNA synthesis
3. Initiation of protein synthesis
4. Protein synthesis chain elongation

2. **Evaluating Option 1: DNA Replication**:
- DNA replication involves the duplication of DNA and requires the enzyme DNA polymerase. Since translocase is not involved in this process, **this option is incorrect**.

3. **Evaluating Option 2: RNA Synthesis**:
- RNA synthesis, also known as transcription, involves synthesizing RNA from a DNA template. This process requires RNA polymerase, not translocase. Thus, **this option is incorrect**.

4. **Evaluating Option 3: Initiation of Protein Synthesis**:
- The initiation of protein synthesis (translation) requires initiation factors and ribosomes (like the 40S and 60S ribosomes). Translocase is not involved in the initiation phase, so **this option is incorrect**.

5. **Evaluating Option 4: Protein Synthesis Chain Elongation**:
- During protein synthesis, after initiation, the elongation phase occurs where amino acids are added to the growing polypeptide chain. This process involves the movement of the ribosome along the mRNA, which is known as translocation. The enzyme responsible for this translocation is translocase. Therefore, **this option is correct**.

### Conclusion:
Translocase is an enzyme required for **protein synthesis chain elongation**.