Question

Which of the following resistance mechanisms describes the function of \(\beta\) -lactamase? a. efflux pump b. target mimicry c. drug inactivation d. target overproduction

Short answer

c. drug inactivation

Step-by-step solution

Understanding the Enzyme \(\beta\)-lactamase

The enzyme \(\beta\)-lactamase is known for breaking down \(\beta\)-lactam antibiotics, such as penicillin. This action involves hydrolyzing the \(\beta\)-lactam ring, rendering the antibiotic ineffective.

Defining Drug Inactivation

Drug inactivation is a resistance mechanism where the antibiotic is chemically altered or destroyed by a bacterial enzyme, making the drug ineffective.

Comparing Mechanisms

Efflux pumps expel antibiotics out of the cell, target mimicry alters the antibiotic's target site to prevent binding, and target overproduction increases the amount of target molecules within the cell. None of these match the inactivation action performed by \(\beta\)-lactamase.

Conclusion

Given that \(\beta\)-lactamase modifies the antibiotic directly, the resistance mechanism must be drug inactivation.

Key concepts

Antibiotic Resistance

Antibiotic resistance is when bacteria develop the ability to survive exposure to antibiotics that would normally kill them or inhibit their growth. This can occur in various ways:

• Mutation: Changes in bacterial DNA can lead to resistance.
• Gene Transfer: Bacteria can acquire resistance genes from other bacteria.

Resistance makes infections harder to treat and can lead to longer illnesses and more hospital visits.

Drug Inactivation

Drug inactivation is a common antibiotic resistance mechanism. Here, bacteria produce enzymes that chemically alter or destroy the antibiotic. This process can involve:

• Breaking down the antibiotic molecule.
• Adding chemical groups to the antibiotic, preventing it from acting.

In the case of \(\beta\)-lactamase, the enzyme breaks down the antibiotic, making it useless against the bacteria.
This is why understanding drug inactivation is crucial in combating antibiotic resistance.

Beta-Lactam Antibiotics

Beta-lactam antibiotics, such as penicillin, are a class of antibiotics that include a wide range of drugs sharing a common chemical structure, known as the \(\beta\)-lactam ring. These antibiotics work by interfering with the synthesis of bacterial cell walls, leading to cell death. Unfortunately, bacteria can develop resistance to these drugs through various mechanisms, one of the most significant being the production of \(\beta\)-lactamases.
By understanding how \(\beta\)-lactam antibiotics and \(\beta\)-lactamases interact, researchers can develop new strategies to overcome bacterial resistance.

Enzyme Function

Enzymes are proteins that catalyze chemical reactions within living organisms. An enzyme's function is highly specific, meaning each enzyme facilitates only one type of reaction. For instance, the enzyme \(\beta\)-lactamase specifically targets and breaks down the \(\beta\)-lactam ring in certain antibiotics. This action deactivates the antibiotic, allowing bacteria to survive.
Understanding enzyme function is critical in biochemistry and medicine. It helps scientists design better antibiotics and develop inhibitors that can block harmful enzymes like \(\beta\)-lactamase.

• Enzyme Active Site: The region of the enzyme where substrate molecules bind and undergo a chemical reaction.
• Substrate: The molecule upon which an enzyme acts.