Drug resistance in bacteria and the mechanisms have become a major source of mortality and morbidity worldwide. When in the 1900s, antibiotics were introduced, it was considered that the world would win the war against microorganisms. However, within a few days, it has been discovered that the microorganisms can develop resistance power inside them to fight against at least some antimicrobial agents. 

This paper will cover the concept of Drug resistance in bacteria and the mechanisms, different definitions of germs and antimicrobials, MRSA resistance mechanism, and the impact of an antimicrobial resistance mechanism.  

Different Definitions of Germs and Antimicrobials 

Antibiotic resistance does not indicate the resistance of the body to antibiotics. However, it depicts that bacteria or fungi have caused the infection, which is resistant to antibiotics. 

Definition of different bacterial and fungus bodies are 

  • Germs: germs refer to microbes. It is the smallest size of living organisms, including viruses, bacteria, fungi, etc.
  • Pathogens: harmful germs are called pathogens, the majority of the germs are not harmful, while some are important to the human body
  • Bacteria: these cause infections such as strep throat, foodborne, and various serious illnesses, which antibiotics can treat
  • Antimicrobials: It describes drugs for treating different infections by slowing or killing pathogens’ growth within living bodies
  • Fungi: fungus causes infections like yeast infection, athlete’s foot, and many serious infections

Persistence and Resistance 

It is important to understand the difference between resistance and persistence before understanding the various aspects of drug resistance in bacteria and the mechanisms. Resistance is a process where all the surrounding cells would be resistant if a bacterium is resistant to a certain antimicrobial agent. On the other hand, persistence is described as the bacterial cells that are non-susceptible to the drug. But it also does not process resistance genes. 

Due to persistence, some cells in a bacterial population can be in a stationary growth phase known as dormant. Therefore, most antibacterial agents do not affect cells that are not actively dividing or growing. 

Concept of Drug Resistance in Bacteria and the Mechanisms 

Against antibiotics, germs create mechanism strategies for surviving. DNA of the terms provides specific proteins to make more resistance mechanisms ad power. 

Resistance mechanism or defence strategies 

Description 

Restrict access to antibiotics

Get rid of the antibiotics

Destroy or change the antibiotics

Bypass the effect of antibiotics

Change the target
  • Germs restrict the way of entry by modifying entryways
  • Using pumps, germs can eliminate antibiotics from entering the walls of cells
  • Germs destroy or change the antibiotics and break down drugs using enzymes and proteins
  • Germs process new cells to process to avoid the target of antibiotics
  • Many drugs are created to describe single parts within a bacterium. It changes the target to make the drugs ineffective

Group Antimicrobial Resistance Mechanisms 

Antimicrobial agents can be divided into groups based on their mechanism of activities of antimicrobial. The main groups are, depolarize the cell membrane, agents that inhibit cell walls, inhibit protein synthesis, inhibit nucleic acid synthesis, and inhibit metabolic pathways.  

Mechanism of actions and antimicrobial groups are, 

Inhibit Cell Wall Synthesis

  • Carbapenems
  • β-Lactams
  • Monobactams
  • Cephalosporins
  • Monobactams
  • Penicillins
  • Glycopeptides

Depolarize Cell Membrane

  • Lipopeptides

Inhibit Protein Synthesis

  • Aminoglycosides
  • Tetracyclines
  • Bind to 30S Ribosomal Subunit
  • Lincosamides
  • Chloramphenicol
  • Macrolides
  • Streptogramins
  • Oxazolidinones

Nucleic Acid Synthesis

  • Quinolones
  • Fluoroquinolones

 Metabolic Pathways

  • Trimethoprim
  • Sulfonamides

Identification of MRSA resistance mechanism

MRSA is resistant to all β-lactams as it has a presence of mecA. It is a gene that produces a penicillin-binding protein. It has a low affinity for β-lactams antibiotics. Staphylococcus aureus is a major veterinary and human pathogen worldwide. MRSA poses a significant difficulty in enduring problems to the infection treatment of such strains. The diagnosis of MRSA resistant mechanism can be checked by tissue sample or nasal secretion for sign drug bacteria that are drug-resistant. 

Impact of Antimicrobial Resistance Mechanisms 

Antimicrobial resistance mechanisms have vital importance in identifying MRSA. The increasing infection of MRSA can increase the health issue and can be fatal even for some cases. It also impacts morbidity and mortality. Therefore the antimicrobial resistance mechanisms can reduce the impact of disease complications.  

Conclusion 

There is a specific mechanism to fight against antimicrobial agents and develop resistance against them. This mechanism is native to the microorganisms or accrued from other microorganisms. Understanding this mechanism can make the treatment option better in treating ineffective diseases, developing antimicrobial drugs, and overall developing the treatment procedure. 

This chapter has defined the impact of antimicrobial resistance mechanisms on MRSA resistance mechanisms. Along with that, it defied the antimicrobial resistance factors as well.