Which class of antibiotics has no anaerobic coverage?

Aminoglycosides are a class of antibiotics that primarily target aerobic bacteria, specifically by inhibiting protein synthesis. They are not effective against anaerobic organisms due to their mechanism of action, which relies on oxygen-dependent transport processes for entry into bacterial cells. Consequently, aminoglycosides such as gentamicin and amikacin do not provide coverage for anaerobic pathogens, making them ineffective against infections caused by anaerobic bacteria.

Cephalosporins, while having some variability based on their generation, also generally lack reliable anaerobic coverage, particularly the earlier generations. The third and fourth generations may provide some coverage against certain anaerobes, but they do not uniformly cover all anaerobic bacteria, especially in comparison to other antibiotic classes that specifically target anaerobic infections.

Given this, the combination of aminoglycosides and cephalosporins signifies that neither class offers reliable coverage for anaerobic bacteria. This aligns with the correct answer, which indicates that both classes have no anaerobic coverage.