/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 100 How are proteins able to provide... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 20: Problem 100

How are proteins able to provide a buffering action?

Short Answer

Expert verified
Proteins provide a buffering action through the ionizable side chains of acidic (Asp and Glu) and basic (Arg, His, Lys) amino acid residues, as well as the N-terminal (-NH2) and C-terminal (-COOH) groups of the protein. These groups can donate or accept protons to maintain a relatively constant pH when acids or bases are added to the solution.

Step by step solution

01

1. Understand protein structure

Proteins are made up of amino acids connected by peptide bonds. Each amino acid has a central carbon atom (C-alpha) bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom, and a side chain (R group) that is unique to each of the 20 commonly occurring amino acids.
02

2. Understand amino acid side chains

The side chains (R groups) of amino acids can be classified into different categories based on their chemical properties. Some of these side chains have acidic or basic properties, which can participate in hydrogen ion interactions and contribute to the buffering capacity of proteins.
03

3. Identify acidic and basic amino acid residues

There are two kinds of amino acid side chains that can contribute to the buffering action of proteins: acidic and basic side chains. Acidic side chains include aspartic acid (Asp) and glutamic acid (Glu), which have carboxyl groups (-COOH) in their side chains. Basic side chains include arginine (Arg), histidine (His), and lysine (Lys), which have amino groups (-NH2) in their side chains.
04

4. Explain the buffering action of acidic and basic side chains

The buffering action of proteins occurs due to the ionizable side chains of acidic and basic amino acid residues. When an acid is added to a protein solution, the acidic side chains of Asp and Glu can act as proton acceptors, while the basic side chains of Arg, His, and Lys can act as proton donors. This counteracts the excess protons from the acid, minimizing the change in pH. Conversely, when a base is added to a protein solution, the basic side chains can accept protons from the solution, and acidic side chains can donate protons to the solution, preventing a substantial pH change.
05

5. Consider the buffering action of N-terminus and C-terminus

In addition to the ionizable side chains of amino acid residues, the N-terminal amino group (-NH2) and the C-terminal carboxyl group (-COOH) of a protein can also participate in buffering action. When the pH of the solution is close to the pKa of N-terminal or C-terminal groups, these groups can also act as proton acceptors or donors, providing additional buffering capacity. In conclusion, proteins provide a buffering action through the ionizable side chains of acidic and basic amino acid residues, as well as the N-terminal and C-terminal groups of the protein. These groups can donate or accept protons to maintain a relatively constant pH when acids or bases are added to the solution.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

What is biochemistry? Are biochemistry and organic chemistry the same thing? How are they related?

Describe the structure of a typical nucleotide. What components are present in the nucleotide?

What general name is given to the molecule acted on by an enzyme? What does it mean to say that an enzyme is specific for this molecule?

What molecule stores and transmits genetic information in the cell? How large is this molecule? Where in the cell is this molecule found?

Choose one of the following terms to match the description given. a. aldohexose n. glycogen b. saliva o. glycoside linkage c. antibody p. hormone d. cellulose q. hydrophobic e. \(\mathrm{CH}_{2} \mathrm{O}\) I. inhibition f. cysteine s. ketohexoses g. denaturation t. oxytocin h. disaccharides u. pleated sheet i. disulfide v. polypeptide j. DNA w. polysaccharides k. enzymes x. primary structure 1\. fibrous y. substrate m. globular z. sucrose substance that has a specific effect on a particular target organ
See all solutions

Recommended explanations on Chemistry Textbooks

Physical Chemistry

Read Explanation

Inorganic Chemistry

Read Explanation

Chemical Analysis

Read Explanation

Nuclear Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Chemical Reactions

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.