A protein 'A' contains $$0.30\%$$ of glycine (molecular weight $$75$$). The minimum molar mass of the protein 'A' is ______ $$\times 10^3$$ g mol$$^{-1}$$ [nearest integer]

We need to find the minimum molar mass of protein A that contains 0.30% glycine.

For the minimum molar mass, we assume the protein contains exactly one molecule of glycine per molecule of protein.

If the molar mass of the protein is $$M$$, then:

$$\text{Percentage of glycine} = \frac{\text{Molecular weight of glycine}}{M} \times 100$$

$$0.30 = \frac{75}{M} \times 100$$

$$M = \frac{75 \times 100}{0.30}$$

$$M = \frac{7500}{0.30}$$

$$M = 25000 \text{ g mol}^{-1}$$

$$M = 25 \times 10^3 \text{ g mol}^{-1}$$

The minimum molar mass of protein A is $$\mathbf{25} \times 10^3$$ g mol$$^{-1}$$.

The correct answer is 25.