Protein Synthesis Lab Report

In this lab we employed various assays utilizing a biuret reagent, coomassie brilliant blue reagent, and ultraviolet light in order to determine the identity of six unknown solutions and the concentration of a bovine serum albumin sample. We were given three samples that lacked protein, and three samples containing proteins, and using a spectrophotometer we assessed the amount of light absorbed versus the light transmitted, based on the principles of the Beer-Lambert Law. The three proteins used included lysozyme, protamine sulfate, and bovine serum albumin, and the three non-protein samples contained either RNA, tyrosine, and glycylglycylglycine. Standard curves were created to exhibit the linear relationship between the concentration of solute (protein, non-protein) and the resulting absorbance.
Anions in CBB assay and Cu2+ ions in biuret assay bind with peptide bonds yield higher absorption, indicating protein presence. UV light is absorbed by compounds containing aromatic structures, providing the identity of protein.

When the biuret assay was completed, the solutions that changed color and absorbed the most amount of light were determined to contain proteins due to the reaction of the copper ions and peptide bonds. Utilizing the CBB assay and the UV assay we determined that solution A was tyrosine, B was protamine sulfate, C was glycylglycylglycine, D was RNA, E was BSA, and F was lysozyme. Analysis of BSA absorbance graphs showed an average of 1.84 mg/mL among all three assays.