menu
bartleby
search
close search
Hit Return to see all results

describe the structural subunits of a bacterial cell wall and how they are arranged

Question

describe the structural subunits of a bacterial cell wall and how they are arranged

check_circleAnswer
Step 1

The major component of the bacterial cell wall is peptidoglycan or murein. This rigid structure of peptidoglycan, specific only to prokaryotes, gives the cell shape and surrounds the cytoplasmic membrane.

Step 2

Murein is the ubiquitous component of bacterial cell walls. Murein is a unique type of peptidoglycan, a polymer of disaccharides (glycan) cross-linked by short chains of amino acids. Many types of peptidoglycan can exist. All bacterial peptidoglycans contain N-acetylmuramic acid, which is the definitive component of murein.

In the Gram-positive Bacteria, the cell wall consists of several layers of peptidoglycan. Running perpendicular to the peptidoglycan sheets is a group of molecules called teichoic acids which are unique to the Gram-positive cell wall. The cell wall is thick (15-80 nanometers), consisting of several layers of peptidoglycan. 

In the Gram-negative Bacteria, the cell wall is composed of a single layer of peptidoglycan surrounded by a membranous structure called the outer membrane. The outer membrane of Gram-negative bacteria invariably contains a unique component, lipopolysaccharide (LPS or endotoxin). In Gram-negative bacteria the outer membrane is usually thought of as part of the cell wall. The cell wall is relatively thin (10 nanometers) and is composed of a single layer of peptidoglycan surrounded by an outer membrane.

Step 3

In the peptidoglycan structure, the glycan backbone is made up of alternating molecules of N-acetylglucosamine (G) and N-acetylmuramic acid (M) connected by a beta 1,4-glycoside bond. The 3-carbon of N-acetylmuramic acid (M) is substituted with a lactyl ether group derived from pyruvate. The lactyl ether connects the glycan backbone to a peptide side chain that contains L-alanine, (L-ala), D-glutamate (D-glu), Diaminopimelic acid (DAP), and D-alanine (D-ala). MurNAc is unique to bacterial cell walls, as is D-glu, DAP and D-ala.

Strands of murein are assembled in the periplasm from about 10...

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Our solutions are written by experts, many with advanced degrees, and available 24/7

See Solution
Tagged in

Science

Biology

Microbiology

Related Biology Q&A

Find answers to questions asked by student like you

Show more Q&A add
question_answer

Q: Which part of the microscope holds the slide or specimen?    the body tube the condenser the fine a...

A: A microscope is an instrument used to see objects that are too small to be seen by the naked eye. Th...

question_answer

Q: X Summative Quiz for Ch: Course Home Homepage - Fall 2019 - Biol B https://www.macmillanhighered.com...

A: The atomic mass is the mass of an atom. It sunit is the unified atomic mass unit where 1 unified ato...

question_answer

Q: Below is a DNA template strand for RNA transcription where the * and “ mark the beginning and end of...

A: Transcription is the process by which the information in a DNA strand (template) is copied into a me...

question_answer

Q: *u B Homepage - Fall 2019 Biol Summative Quiz for Cha X https://www.macmillanhighered.com/launchpad/...

A: Triglyceride is an ester that is derived from glycerol and three fatty acids. They are the main cons...

question_answer

Q: How are the heart rate and pulse rate related?

A: The heart rate can be defined as the number of times the heartbeats in the duration of a minute.Wher...

question_answer

Q: 3. Gliadin peptides can be classified as "toxic" or "immunogenic" depending on how they induce intes...

A: Amino acids are building blocks of proteins, which are essential for the organisms to undergo basic ...

question_answer

Q: The ____________ follows the coronary sulcus around the heart and supplies blood to the left atrium ...

A: The cardiovascular system is also known as the circulatory system that allows the blood flow through...

question_answer

Q: what % of all extant plants have vascular tissue?

A: The vascular plants, or tracheophytes, are the dominant and most conspicuous group of land plants. T...

question_answer

Q: Describe methods used to grow microbes anaerobically and under high CO2 conditions

A: An anaerobic organism does not require oxygen for its growth. It may react negatively or may even di...

Sorry about that. What wasn’t helpful?