Which of the following amino acid is present only in bacteria and BGA

Options

A. Glycine
B. Tyrosine
C. Glutamic acid
D. Diaminopimelic acid

Answer

To determine which amino acid is present only in bacteria and blue-green algae (BGA), we can follow these steps:

### Step 1: Understand the options provided
The options given are:
- Glycine
- Tyrosine
- Glutamic acid
- Diaminopimelic acid

### Step 2: Analyze the amino acids
1. **Glycine**: This is a common amino acid found in many organisms, including humans.
2. **Tyrosine**: This amino acid is also widely distributed in various organisms, including animals and plants.
3. **Glutamic acid**: Like glycine and tyrosine, glutamic acid is present in many organisms, including humans.
4. **Diaminopimelic acid**: This amino acid is specifically found in the cell walls of bacteria and cyanobacteria (blue-green algae).

### Step 3: Identify the unique amino acid
From the analysis:
- Glycine, tyrosine, and glutamic acid are not exclusive to bacteria or BGA; they are found in many other organisms.
- Diaminopimelic acid is unique to bacteria and blue-green algae, as it is a component of peptidoglycan, which is a major part of their cell walls.

### Conclusion
The amino acid that is present only in bacteria and blue-green algae is **diaminopimelic acid**.

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