If Staphylococcus aureus V8 protease is specific for acidic amino acids, which of the following residues would be cleaved by this protease?

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11ecba2d_128c_6c3d_a3bf_85fc931eb0a0_MD0008_00 Amino acids are the fundamental components of proteins and contain three main constituents: An amino group, a carboxyl group, and a side chain, which are all bonded to one carbon atom (the α-carbon). Amino acids differ only in the structure of the side chain, which contains different functional groups with varying characteristics. Therefore, amino acids can be grouped together and classified based on their side chain functional groups. Four common amino acid classifications include hydrophilic, hydrophobic, acidic, and basic. Acidic amino acids have a side chain with a proton-donating (acidic) functional group that is negatively charged at physiological pH. The amino group is protonated (positively charged) and the carboxyl group is deprotonated (negatively charged) at physiological pH, giving amino acids with uncharged side chains a zero net charge. Therefore, acidic amino acids have a −1 net charge at physiological pH because they have charged side chains. Staphylococcus aureus V8 protease specifically cleaves peptide bonds at the carboxyl terminal of acidic amino acids. The distinguishing feature of acidic amino acids is the carboxyl group at the end of the side chain. The only answer choice with a carboxyl group as part of the side chain is aspartic acid. (Choices A, C, and D) These amino acids are methionine, arginine, and threonine, which can be classified as hydrophobic, basic, and hydrophilic, respectively. Educational objective: Amino acids are the fundamental components of proteins and are made of an amino group, a carboxyl group, and a side chain. The structure of amino acids differs only in the side chains, which are made of different functional groups with varying characteristics. Amino acids can therefore be grouped based on their side-chain classification, including hydrophilic, hydrophobic, acidic, or basic.

If Staphylococcus Aureus V8 Protease Is Specific for Acidic Amino