The first nif genes were isolated from

Options

A. Klebsiella aerogenosa
B. Klebsiella oxytoca
C. Klebstella pneumoniae
D. Klebsiella granulomatis

Answer

**Step-by-Step Solution:**

1. **Understanding NIF Genes**: NIF genes are responsible for nitrogen fixation, which is the process of converting atmospheric nitrogen into a form that plants can use.

2. **Identifying the Source**: The first NIF genes were isolated from specific organisms. The transcript mentions several names, but we need to focus on the correct one.

3. **Listing the Organisms**: The transcript refers to various organisms such as Clavacilla, Erygognitia, and others. However, it specifically mentions Clavacilla pneumonia as the first isolate.

4. **Confirming the Isolation**: It is stated that when Clavacilla pneumonia was isolated and transferred, the roots of the plants were filled with nitrogen fixation, indicating its significance in this process.

5. **Final Answer**: Based on the information provided, the first NIF genes were isolated from Clavacilla pneumonia.

**Final Answer**: The first NIF genes were isolated from Clavacilla pneumonia.

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