Nope.
Consider these two peptide
Met-Val-Tyr-Asp-Pro-Trp-Val
Met-Pro-Trp-Val-Val-Tyr-Asp
Same molecular weight. A digest yields the same amino acids. But they're different because the sequence of peptides is different.
Consider these two peptide
Met-Val-Tyr-Asp-Pro-Trp-Val
Met-Pro-Trp-Val-Val-Tyr-Asp
Same molecular weight. A digest yields the same amino acids. But they're different because the sequence of peptides is different.