Why don't some bacteria become resistant to antibiotics ?

Some bacterial species, such as Neisseria meningitidis and Streptococcus pyogenes, do not show a significant increase in resistance to penicillin and its derivatives, despite the global trend. An understanding of this "fortunate" phenomenon could also shed light on the ecological significance of resistance, and offer interesting angles of attack for its control. The metabolism of peptidoglycan, the basic structure of the bacterial wall, its synthesis and renewal are at the heart of this question. In their human niche, these bacteria are part of a complex equilibrium involving the bacterium, the definition of its shape, physiology and metabolism, the host's perception of these bacteria and the intensity of its response (innate immunity, inflammation), the selective pressure of antibiotics (beta-lactams in this case) and the subsequent selection of resistant microorganisms due to the selection of modifications in the targets that are the effectors of peptidoglycan synthesis. It appears that, in these particular species, these modifications have a high fitness cost, which is counter-selective in terms of survival capacity in the host and resistance to its defenses. This notion of fitness cost, which is highly visible in these two species, is perhaps a more general phenomenon that should be explored and possibly exploited to counter-select bacteria carrying multiple resistances.