Antibiotics and Antimicrobials

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Questions and Answers

Which of the following best describes the distinction between antimicrobial and antibiotic agents?

  • Antibiotics are used for external applications, while antimicrobials are for internal use.
  • Antibiotics are a subset of antimicrobial agents, targeting only bacteria, whereas antimicrobials cover bacteria, viruses, and other microorganisms. (correct)
  • Antimicrobial agents specifically target bacterial growth, while antibiotics have a broader spectrum, including viruses.
  • Antimicrobials are naturally derived, whereas antibiotics are synthetically produced.

Why do a small percentage of discovered antibiotics possess commercial value?

  • Most antibiotics are too expensive to mass produce.
  • The majority of antibiotics are only effective against viral infections.
  • Many antibiotics have a very narrow spectrum of activity and bacteria rapidly develop resistance. (correct)
  • Most antibiotics are discovered in environments where they outcompete with existing drugs.

What is a primary reason why many potential antibiotics identified during research are deemed unsuitable for medicinal use?

  • They exhibit toxicity or adverse effects on humans. (correct)
  • They are too expensive to synthesize on a large scale.
  • They are ineffective against a broad spectrum of bacteria.
  • They are rapidly degraded by bacterial enzymes.

How is a hospital-acquired infection (HAI) typically defined?

<p>An infection manifesting 48 hours or later after hospital admission that was not present upon admission. (A)</p> Signup and view all the answers

What is the defining characteristic of a community-acquired infection (CAI)?

<p>It is contracted outside of a healthcare facility. (C)</p> Signup and view all the answers

What is the primary ecological rationale behind the production of antibiotics by fungi and bacteria in natural environments?

<p>To gain a competitive advantage by eliminating competing microorganisms. (B)</p> Signup and view all the answers

Why is the development of synthetic antibiotics considered a crucial strategy in combating bacterial infections?

<p>Bacteria take longer to develop resistance to synthetic compounds with no natural analog because they may lack pre-existing mechanisms to counteract them. (D)</p> Signup and view all the answers

What is a key advantage of rational drug design in antibiotic development?

<p>It enables the targeted design of molecules to inhibit specific bacterial proteins or pathways, potentially minimizing off-target effects. (B)</p> Signup and view all the answers

What is a major advantage of using narrow-spectrum antibiotics over broad-spectrum antibiotics?

<p>Narrow-spectrum antibiotics are less likely to contribute to antibiotic resistance in diverse bacterial populations. (B)</p> Signup and view all the answers

You are treating a patient with a severe infection, but the causative bacterial species is unknown. What would be the MOST appropriate initial approach regarding antibiotic treatment?

<p>Prescribe a broad-spectrum antibiotic to target a wide array of potential pathogens while awaiting lab results. (A)</p> Signup and view all the answers

A newly discovered antibiotic is found to slow bacterial growth by interfering with protein synthesis, but does not kill the bacteria. How should this antibiotic be classified?

<p>Bacteriostatic (B)</p> Signup and view all the answers

What is the significance of determining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of a new antibiotic?

<p>To identify the concentrations required to inhibit bacterial growth and kill bacteria, respectively. (B)</p> Signup and view all the answers

Beta-lactam antibiotics target which essential bacterial process?

<p>Cell wall synthesis (B)</p> Signup and view all the answers

Why are beta-lactam antibiotics more effective against gram-positive bacteria?

<p>Gram-positive bacteria have a thicker peptidoglycan layer in their cell wall. (C)</p> Signup and view all the answers

What is the mechanism of resistance employed by bacteria against beta-lactam antibiotics?

<p>Producing enzymes called beta-lactamases that degrade the antibiotic. (D)</p> Signup and view all the answers

What is the direct consequence of disrupting the bacterial plasma membrane with antibiotics like polymyxins?

<p>Disruption of the cell's osmotic balance and subsequent lysis (D)</p> Signup and view all the answers

How do aminoglycoside antibiotics inhibit bacterial growth?

<p>By causing misreading of the mRNA codon during protein synthesis (A)</p> Signup and view all the answers

Why might cancer patients taking methotrexate (MTX) be more susceptible to bacterial infections, and how does this relate to antibiotic resistance?

<p>MTX inhibits DNA synthesis in both human and bacterial cells, and may stimulate resistance mechanisms. (C)</p> Signup and view all the answers

What is the primary mechanism of action of antibiotics that target the bacterial ribosome?

<p>Interfering with protein synthesis (C)</p> Signup and view all the answers

Why do antibiotics that inhibit protein synthesis by targeting ribosomes exhibit varied selectivity between gram-positive and gram-negative bacteria?

<p>The ribosomes in gram-positive and gram-negative bacteria have slight structural differences due to evolutionary divergence. (A)</p> Signup and view all the answers

What is the primary mechanism by which sulfonamide antibiotics inhibit bacterial growth?

<p>Inhibiting folate synthesis (D)</p> Signup and view all the answers

Why is a multidrug treatment or 'cocktail' often required for treating Mycobacterium tuberculosis infections?

<p><em>Mycobacterium tuberculosis</em> is highly prone to developing antibiotic resistance, necessitating multiple drugs to ensure bacterial clearance (C)</p> Signup and view all the answers

How does isoniazid (INH) specifically target Mycobacterium tuberculosis?

<p>It inhibits the synthesis of mycolic acid, a component unique to mycobacterial cell walls. (D)</p> Signup and view all the answers

What is the MOST critical factor that necessitates strict adherence to a multi-drug treatment plan for tuberculosis, even after symptom remission?

<p>To avoid the development of antibiotic resistance in any remaining bacteria. (A)</p> Signup and view all the answers

What is a significant evolutionary mechanism that enables bacteria to rapidly adapt and develop antibiotic resistance?

<p>Horizontal gene transfer, facilitating the spread of resistance genes between bacteria. (C)</p> Signup and view all the answers

How does challenging a bacterial population with antibiotics lead to the selection of antibiotic-resistant strains?

<p>Antibiotics create a selective pressure, favoring the survival and reproduction of bacteria with pre-existing resistance mechanisms. (C)</p> Signup and view all the answers

What is the role of plasmids in the spread of antibiotic resistance among bacteria?

<p>Plasmids are small, circular DNA molecules that can carry antibiotic resistance genes and be transferred between bacteria through conjugation. (D)</p> Signup and view all the answers

What is bacterial conjugation, and how does it contribute to the spread of antibiotic resistance?

<p>A mechanism where bacteria directly transfer genetic material, often plasmids containing resistance genes, to another bacterium. (C)</p> Signup and view all the answers

How does bacterial transformation facilitate the acquisition of antibiotic resistance?

<p>It involves the uptake of free DNA fragments from the environment by bacteria. (C)</p> Signup and view all the answers

What is the MOST effective way to minimize the overuse of antibiotics in medicine?

<p>Restricting antibiotic prescriptions to severe bacterial infections only and promoting diagnostic testing to confirm bacterial etiology. (B)</p> Signup and view all the answers

Why is the routine use of antibiotics in agriculture, particularly for promoting growth in livestock, a significant concern regarding antibiotic resistance?

<p>It leads to the selection and spread of antibiotic-resistant bacteria in both animals and the environment, potentially affecting human populations. (B)</p> Signup and view all the answers

Patients on long term medication are commonly known to abruptly cease their treatment once they start feeling better. Why would this cause problems in a bacterial infection?

<p>The bacteria with the highest antibiotic resistance will survive, regrow, and reinfect the host. (B)</p> Signup and view all the answers

What is a spheroplast, how is it formed, and why are they clinically relevant?

<p>A bacteria with removed cell wall, generated with beta-lactam antibioitics (D)</p> Signup and view all the answers

Which option correctly orders the events involved in bacterial populations?

<p>Mutation, conjugation, transformation (C)</p> Signup and view all the answers

A farmer has animals raised for beef production. What would the negative consequences of regularly administrating antibiotics be?

<p>Selection and spread of antibiotic resistence in the animals and environment. (C)</p> Signup and view all the answers

Which choice is the correct mechanism of action order?

<p>Cell wall synthesis, disruption of plasma membrane, inhibition of DNA. (D)</p> Signup and view all the answers

There are many cases when an infection is polymicrobial. What action is BEST given this information?

<p>Administer a anti-biotic cocktail to the patient. (A)</p> Signup and view all the answers

What are the correct methods to prevent mutation?

<p>There is no way to completly prevent mutations. (D)</p> Signup and view all the answers

During the process of protein synthesis, how do antibiotics interfere with the ribosome binding sites?

<p>By preventing tRNAs from bindint and interfering with chain elongation. (D)</p> Signup and view all the answers

Where do antibiotics bind to in bacterial cells to inhibit the function of these specific cellular processes?

<p>They can bind to ribosomes, degrade the cell wall, block DNA replication, and disrupt the cell's osmotic balance. (D)</p> Signup and view all the answers

How does the ecological role of antibiotic production by Penicillium mold directly benefit the organism?

<p>By eliminating competition from bacteria and other microorganisms, securing a larger share of available nutrients. (B)</p> Signup and view all the answers

Why is the development of a completely novel synthetic antibiotic molecule considered advantageous in overcoming bacterial resistance?

<p>Bacteria may take longer to evolve resistance mechanisms against synthetic compounds lacking natural analogs. (A)</p> Signup and view all the answers

What is the rationale behind using computer modeling in the rational design of antibiotics?

<p>To simulate the interaction of potential drugs with bacterial protein structures, optimizing their fit and binding. (D)</p> Signup and view all the answers

How does targeting a bacterial protein with no equivalent in human cells during rational antibiotic design minimize potential side effects?

<p>It reduces the likelihood of the antibiotic interfering with essential human cellular processes. (B)</p> Signup and view all the answers

In what situation would a broad-spectrum antibiotic be MOST appropriately prescribed?

<p>Empirically, for a severe, life-threatening infection when the causative agent is unknown. (B)</p> Signup and view all the answers

Which statement BEST contrasts bacteriostatic and bactericidal antibiotics in terms of their mechanism of action?

<p>Bactericidal antibiotics lead to bacterial death by targeting essential structures or processes, while bacteriostatic antibiotics inhibit growth without directly causing cell death. (B)</p> Signup and view all the answers

Why is determining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) crucial during antibiotic development?

<p>To establish the effective dosage range and understand whether the antibiotic inhibits or kills bacteria at clinically relevant concentrations. (D)</p> Signup and view all the answers

How does the beta-lactam ring in penicillin-like antibiotics lead to the inhibition of bacterial cell wall synthesis?

<p>It irreversibly binds to and inhibits transpeptidases, preventing the cross-linking of peptidoglycans in the cell wall. (C)</p> Signup and view all the answers

Why are gram-positive bacteria generally more susceptible to beta-lactam antibiotics compared to gram-negative bacteria?

<p>Gram-positive bacteria lack an outer membrane, allowing beta-lactams direct access to the peptidoglycan layer. (B)</p> Signup and view all the answers

What mechanism do bacteria employ to resist the effects of beta-lactam antibiotics?

<p>Producing enzymes that modify and inactivate the antibiotic. (B)</p> Signup and view all the answers

How do polymyxins disrupt bacterial plasma membranes, leading to cell death?

<p>By inserting into the membrane and increasing its permeability, leading to leakage of cellular contents. (C)</p> Signup and view all the answers

How do aminoglycoside antibiotics interfere with bacterial protein synthesis?

<p>By causing misreading of the genetic code, leading to the production of non-functional proteins. (B)</p> Signup and view all the answers

What explains the increased susceptibility of cancer patients taking methotrexate (MTX) to bacterial infections that further can lead to antibiotic resistance?

<p>MTX inhibits bacterial DNA synthesis and concurrently stimulates bacterial response where they develop mechanisms for antibiotic resistance. (B)</p> Signup and view all the answers

How do antibiotics targeting bacterial ribosomes achieve selectivity, affecting bacterial protein synthesis while minimizing harm to the host?

<p>By exploiting the structural differences between bacterial and eukaryotic ribosomes. (C)</p> Signup and view all the answers

By what mechanism do sulfonamide antibiotics inhibit bacterial growth?

<p>By competitively inhibiting an enzyme involved in folic acid synthesis. (D)</p> Signup and view all the answers

What is the primary reason multidrug therapy is essential in treating Mycobacterium tuberculosis infections?

<p>To overcome the high rate of spontaneous mutations and prevent the emergence of drug-resistant strains. (C)</p> Signup and view all the answers

Isoniazid (INH) is a key component of tuberculosis treatment because it inhibits the synthesis of what?

<p>Mycolic acid, a unique component of the mycobacterial cell wall. (C)</p> Signup and view all the answers

Why is patient compliance with the full course of a multi-drug tuberculosis treatment so critical, even after symptoms improve?

<p>To ensure complete eradication of the bacteria and prevent the development of drug resistance. (D)</p> Signup and view all the answers

What evolutionary mechanism allows bacteria to adapt rapidly and develop antibiotic resistance effectively?

<p>Short generation times and horizontal gene transfer, facilitating rapid adaptation and resistance spread. (D)</p> Signup and view all the answers

How does antibiotic use contribute to the selection and proliferation of antibiotic-resistant bacteria?

<p>Antibiotics kill susceptible bacteria, allowing resistant strains to thrive due to reduced competition. (C)</p> Signup and view all the answers

What role do plasmids play in the dissemination of antibiotic resistance among bacterial populations?

<p>Plasmids serve as vectors for the transfer of resistance genes between bacteria through horizontal gene transfer. (C)</p> Signup and view all the answers

How does bacterial conjugation contribute to the spread of antibiotic resistance?

<p>It facilitates the transfer of plasmids containing resistance genes between bacteria, even of different species. (C)</p> Signup and view all the answers

How does bacterial transformation lead to the acquisition of antibiotic resistance?

<p>By allowing bacteria to incorporate free DNA containing resistance genes from their environment. (B)</p> Signup and view all the answers

Which strategy would BEST minimize the overuse of antibiotics in clinical settings?

<p>Adopting diagnostic tests to confirm bacterial infections and guide targeted antibiotic therapy. (C)</p> Signup and view all the answers

What is the primary concern regarding the routine use of antibiotics in livestock for growth promotion?

<p>It contributes to the development and spread of antibiotic-resistant bacteria, threatening human health. (A)</p> Signup and view all the answers

Why is abruptly discontinuing antibiotic treatment, after initial symptom improvement, detrimental in bacterial infections?

<p>It allows the survival and regrowth of more resistant bacteria, leading to recurrence and potential resistance. (B)</p> Signup and view all the answers

What is a spheroplast, and why are spheroplasts clinically relevant?

<p>A bacterium that has lost its cell wall, making it vulnerable to osmotic lysis and contributing to antibiotic effectiveness. (A)</p> Signup and view all the answers

If a bacterium has the following mechanisms, what order is correct? 1. Blocks cell wall synthesis 2. Transcription and translation block. 3. DNA replication block. 4. Causes membrane damage

<p>1, 3, 2, 4 (A)</p> Signup and view all the answers

Which choice is the correct mechanism of action order? 1. Translation blocked 2. Cell wall blocked 3. DNA blocked

<p>2, 1, 3 (D)</p> Signup and view all the answers

What is the MOST important factor that makes bacteria change so quickly in the face of antibiotics?

<p>Bacteria are able to reproduce quickly and obtain mutations over very small periods of time. (B)</p> Signup and view all the answers

If an infection is suspected in a patient, but no culture has verified any growth, what should a doctor do?

<p>Wait for the culture to grow. (B)</p> Signup and view all the answers

How do bacterial efflux pumps contribute to antibiotic resistance?

<p>By actively transporting antibiotics out of the bacterial cell, reducing their intracellular concentration. (A)</p> Signup and view all the answers

What is the significance of the observation that antibiotic resistance genes are often located on mobile genetic elements like plasmids or transposons?

<p>It facilitates the rapid spread of resistance genes among diverse bacterial populations through horizontal gene transfer. (B)</p> Signup and view all the answers

Give the correct order associated with molecular adaptations of antibiotic resistance. 1= Target modification, 2= Antibiotic inactivation, 3= Efflux pumps.

<p>2, 1, 3: By enzymatic degradation or modification of the antibiotic. (A)</p> Signup and view all the answers

What is the limitation of prescribing antibiotics without proper discernment?

<p>Widespread resistance is a major consequence. (B)</p> Signup and view all the answers

Why might the development of a novel synthetic antibiotic, with no naturally occurring analog, potentially lead to a longer period before bacteria develop resistance compared to antibiotics derived from natural sources?

<p>Bacteria possess pre-existing enzymes to degrade natural compounds, but not entirely novel synthetic structures. (B)</p> Signup and view all the answers

What primary advantage does rational antibiotic design offer in creating drugs that are more effective and less likely to cause harm to human patients?

<p>Rational design allows for the targeting of bacterial proteins unique to bacteria, limiting off-target effects in human cells. (C)</p> Signup and view all the answers

A patient is prescribed a broad-spectrum antibiotic for a suspected polymicrobial infection. What is a significant risk associated with this treatment approach that clinicians must carefully consider?

<p>The antibiotic may selectively promote the growth of resistant strains, complicating future treatment options. (A)</p> Signup and view all the answers

What is a critical consideration when prescribing bacteriostatic antibiotics compared to bactericidal antibiotics?

<p>The patient's immune system must be competent to clear the inhibited bacteria when using bacteriostatic antibiotics. (D)</p> Signup and view all the answers

How does the presence of mycolic acid in the cell wall of Mycobacterium tuberculosis influence the selection of antibiotics used for treatment?

<p>Mycolic acid prevents the entry of most antibiotics, necessitating the use of drugs that can penetrate this barrier, such as isoniazid. (C)</p> Signup and view all the answers

Flashcards

Antimicrobial

Broader group that includes viruses.

Antibiotic

Specific to bacterial growth inhibition or death.

Hospital-acquired infection

Infections acquired in a hospital, showing symptoms after 48 hours of admission.

Community-acquired infection

Infections acquired outside a hospital, with symptoms appearing within 48 hours of hospitalization.

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Natural antibiotics

Antibiotics sourced from fungi or bacteria.

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Synthetic antibiotics

Antibiotics designed and developed in a lab.

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Rational design

Designing drugs by targeting specific components in bacterial cells using computer modeling.

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Broad-spectrum antibiotic

Effective against a wide range of bacterial infections, targeting both gram-positive and gram-negative bacteria.

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Narrow-spectrum antibiotic

Effective against a specific group or type of bacteria, such as gram-positive bacteria.

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Bacteriostatic

Slows down cell growth or inhibits DNA/protein synthesis but doesn't outright kill bacteria.

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Bactericidal

Drugs that outright kill bacteria by disrupting cell walls.

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Minimum Inhibitory Concentration (MIC)

Minimum concentration required to inhibit bacterial growth.

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Minimum Bactericidal Concentration (MBC)

Minimum concentration required to kill bacteria.

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Beta-lactamase

Enzymes produced by bacteria that break down the beta-lactam ring, making the antibiotic non-functional.

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Plasmids

Extra, smaller circular DNAs in bacteria cells that can be transferred to other cells.

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Conjugation

Bacterial process where cells share plasmids.

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Transformation

Process where bacteria pick up free DNA chunks from the environment and incorporate them into their own genome.

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Study Notes

Antibiotics vs. Antimicrobials

  • Antimicrobials are a broad group that includes antivirals, while antibiotics specifically target bacteria.
  • Less than 1% of antibiotics have commercial value due to bacterial changes over time, making specific antibiotics less useful.

Antibiotic Types

  • Broad-range antibiotics target a wide range of bacteria.
  • Narrow-range antibiotics are specific to certain bacteria.

Antibiotic Resistance

  • Antibiotic resistance is a significant problem.
  • Some antibiotics are too toxic for humans, limiting their use.

Infection Classifications

  • Hospital-acquired infections are acquired after 48 hours in the hospital.
  • Community-acquired infections are acquired outside the hospital, with symptoms appearing within 48 hours of hospitalization.

Antibiotic Discovery

  • Antibiotics can come from natural sources like fungi and bacteria, or can be synthesized.
  • Fungi and bacteria produce antibiotics for competition, killing competitors for resources.

Synthetic vs. Natural Antibiotics

  • Synthetic antibiotics are developed due to increasing antibiotic resistance in livestock and human populations.
  • Synthetic antibiotics may take bacteria longer to develop resistance to because they are novel.
  • Rational design involves using computer modeling to design molecules that bind to bacterial proteins.

Rational Design

  • Rational design allows targeting specific components in bacterial cells and identifying potential toxic effects.
  • It enables structured design rather than random screening of natural molecules.

Broad vs. Narrow Spectrum Antibiotics

  • Broad-spectrum antibiotics target a wide range of bacterial infections, including both gram-positive and gram-negative bacteria.
  • Narrow-spectrum antibiotics target specific bacteria, such as penicillin targeting gram-positive bacteria.
  • Broad-spectrum antibiotics are used in emergencies when the specific bacteria causing the infection is unknown or when multiple bacteria are suspected.

Structural Classes of Drugs

  • Cyclic lipopeptides treat gram-positive bacterial infections, including multi-drug resistant strains like MRSA.
  • Glycopeptides, like vancomycin, target gram-positive bacteria, effective against resistant strains.

Bacteriostatic vs. Bactericidal

  • Bacteriostatic antibiotics slow down cell growth by inhibiting DNA or protein synthesis, eventually leading to cell death.
  • Bactericidal antibiotics outright kill bacterial cells, often by disrupting the cell wall.
  • An example of bacteriostatic drugs are those interfering with protein synthesis.
  • Examples of bactericidal drugs are the penicillins.

Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC)

  • Drug companies determine the mechanism of action (bactericidal or bacteriostatic) and the minimum concentrations required to inhibit (MIC) or kill (MBC) bacteria.
  • Initial testing involves in vitro studies, followed by cell cultures and animal models before human trials.

Inhibition of Cell Wall Synthesis

  • Beta-lactams block enzymes required for peptidoglycan synthesis, targeting gram-positive bacteria and acting as bactericidal agents.
  • Resistance to beta-lactams occurs through beta-lactamase, an enzyme that breaks down the beta-lactam ring.
  • Disruption of the cell wall leads to spheroplasts, which are vulnerable to osmotic pressure and lysis.

Disruption of Plasma Membrane

  • Polymyxins disrupt the inner and outer cell membranes of bacteria.
  • Daptomycin targets gram-positive bacteria, while colistin targets gram-negative bacteria and growth of bacteria.

Inhibition of Protein Synthesis

  • Aminoglycosides cause misreading of tRNA codons.
  • Tetracycline inhibits tRNA binding.
  • Streptomycin inhibits initiation translation.
  • Macrolides prevent protein allocation and interfere with ribosomes.
  • The ribosomes between gram-positive and gram-negative bacteria differ slightly, affecting drug binding.
  • This class of antibiotics all interacts with ribosomes.

Inhibition of Metabolic Pathways

  • Sulfonamides inhibit folate synthesis, which is required for DNA synthesis, acting as broad-spectrum bacteriostatic agents.
  • Sulfa allergies are common, requiring careful patient screening.

Multi-Drug Treatments

  • Multi-drug treatments involve using multiple drugs in a cocktail to treat conditions like tuberculosis (TB).
  • TB treatment requires a cocktail of drugs to combat antibiotic resistance.
  • Isoniazid inhibits mycolic acid synthesis specific to mycobacteria cell walls (bactericidal).
  • Ethambutol is bacteriostatic.
  • Multi-drug treatment plans for TB are lengthy (four months or more).
  • Patients may stop taking drugs due to discomfort, leading to the survival of highly resistant bacteria.
  • If patients stop taking the cocktail and get sick again, the original plan is now ineffective.
  • In rural areas, nurses may administer drugs to ensure compliance.

General Complications of Antibiotic Use

  • Antibiotic resistance happens when the drug is no longer effective.
  • The bacterial receptors/proteins change, or develop new proteins thanks to evolutionary changes.
  • Antibiotic resistance can happen through evolutionary mechanisms.
  • Overuse of antibiotics in medicine and agriculture contributes to resistance.

Evolutionary Mechanisms

  • Bacteria can accumulate mutations rapidly due to their short generation time.
  • Exposure to antibiotics selects for bacteria with resistance traits, leading to adaptation.
  • Bacteria adaptation can change efflux pumps or result in receptor adaptation.

Plasmids and Conjugation

  • Plasmids are extra, smaller, circular DNAs in bacteria cells.
  • Plasmids are not chromosomes, they are extra DNA.
  • Bacteria can transfer plasmids to other cells through conjugation.
  • During conjugation, a protein bridge forms between cells, and a single strand of the plasmid is transferred.
  • Both cells then have the plasmid, which often contains antibiotic resistance genes.
  • This is crucial in hospitals, where antibiotic resistance can spread via plasmids.

Transformation

  • Transformation is another mechanism for bacteria to acquire DNA from the environment.
  • A bacterium picks up free chunks of DNA and incorporates them into its genome.
  • Bacteria needs to uptake via big pore in membrane, that imports long pieces of DNA.
  • If the DNA contains antibiotic resistance genes, the bacterium becomes resistant.

Summary of Antibiotic Resistance Mechanisms

  • Random mutation is the slowest method of resistance.
  • Conjugation and transformation occur much faster than random combination.

Examples of Antibiotic Resistance

  • MRSA (methicillin-resistant Staphylococcus aureus) demonstrates antibiotic resistance.

Key Considerations

  • It is important not to overuse antibiotics in medicine to prevent the development of resistance.
  • Antibiotics are often overused in agriculture to promote faster growth in animals. This is now regulated in some countries.

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