Which is not characteristic of Gram (+) bacteria

Options

A. Smooth cell wall
B. Outer membrane
C. Prominent mesosomes
D. Two rings in basal body of flagellum

Answer

To determine which characteristic is not associated with Gram (+) bacteria, we can analyze the options provided:

1. **Smooth Cell Wall**: Gram (+) bacteria have a thick peptidoglycan layer in their cell wall, which can be described as smooth. This is a characteristic of Gram (+) bacteria.

2. **Outer Membrane**: Gram (+) bacteria do not possess an outer membrane. This feature is characteristic of Gram (-) bacteria, which have an outer membrane composed of lipopolysaccharides. Therefore, this option is likely the correct answer to the question.

3. **Prominent Mesosomes**: Mesosomes are invaginations of the plasma membrane found in Gram (+) bacteria. They are often more prominent in these bacteria compared to Gram (-) bacteria, making this option a characteristic of Gram (+) bacteria.

4. **Two Rings in Basal Body Flagellum**: Gram (+) bacteria typically have a flagellum structure that includes two rings in the basal body. This is a characteristic feature of Gram (+) bacteria.

Based on the analysis, the characteristic that is not associated with Gram (+) bacteria is the **outer membrane**.

### Final Answer:
The characteristic that is not associated with Gram (+) bacteria is the **outer membrane**.