During DNA synthesis in bacteria which of the following enzyme is not required ?
(1) DNA dependent DNA polymerase.
(2) DNA dependent RNA polymerase.
(3) RNA dependent DNA polymerase.
(4) DNA gyrase .

Explanation

To determine which enzyme is not required during DNA synthesis in bacteria, we can analyze the options provided:

1. **DNA dependent DNA polymerase**: This enzyme is responsible for synthesizing DNA from a DNA template. It is crucial for DNA replication in both prokaryotes (like bacteria) and eukaryotes. Therefore, it is required for DNA synthesis in bacteria.

2. **DNA dependent RNA polymerase**: This enzyme synthesizes RNA from a DNA template. While it is essential for transcription (the process of making RNA), it is not directly involved in DNA synthesis. However, it is still a necessary enzyme for the overall functioning of the cell, but it does not play a role in the actual replication of DNA.

3. **RNA dependent DNA polymerase**: This enzyme synthesizes DNA from an RNA template, which is not typically involved in the standard DNA replication process in bacteria. However, it is important in certain contexts, such as in retroviruses. In the context of bacterial DNA synthesis, it is not required.

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