A study of certain human diseases (e.g., tuberculosis, syphilis) in the U. S. reveals that antibiotics that were once very effective are no longer useful in treating these bacterial infections. Bacterial species have developed a resistance to these ‘miracle drugs’. Which of the following statements is most likely false?
A) Bacterial populations are evolving.
B) Antibiotic resistance probably arose in bacterial populations due to variation that exists among bacteria or possibly arose through mutation.
C) The basis for antibiotic resistance in bacterial populations is unknowable and resides outside the realm of scientific inquiry.
D) Non-random survivorship caused by natural selection is the underlying cause for this growing problem.
E) Doctors need to be more selective when dispensing antibiotics to patients. They only add to the problem by over-prescribing antibiotics or using these drugs at too low a dose or for too short a duration
The correct answer is C. We know much about why many different types of bacteria become resistant to certain antibiotics. Mechanism deduced by research include:
1) Direct alteration of the antibiotic by the bacterium so that it becomes unable to have the desired effect.
2) Increased effusion (removal) of antibiotic from the bacterial cell via micro-molecular protein pumps (which literally pump antibiotic out of the bacterium ).
3) Decreased permeability of the bacterium to the antibiotic (i.e. stopping the antibiotic from entering the bacterial cell in the first place).
Each of these mechanisms are genetically dictated, and thus rely on mutations of bacterial DNA.