Antibiotic resistant bacteria are a serious problem for us. At present they are killing 23,000 humans per year in the USA alone. The Chief Medical Officer for England has described the situation we are approaching as an "apocalyptic scenario." It's never a good sign when officials in the UK start describing things as apocalyptic, given their cultural preference for understatement.
Our friends -- and I use that term in the loosest possible sense, believe me -- in the pharmaceutical industry have not seen fit to produce any new classes of antibiotics to combat this rising threat. This is not my area of expertise; my best skills are in electrical engineering, not microbiology. However, given our... situation... I have concluded that any attempts to help will yield better results than inaction. I'd rather have stopgap kludges than no solutions at all.
Besides, it's probably better to have public health matters in the hands of people who *don't* think that it's a good idea to hold people's health for ransom in exchange for currency. Why we tolerate drug companies demanding such excessive fees for their treatments and cures is beyond me, but I'm not writing this because I feel like ranting on the internet. We have plenty of people working on that already. We are not at the point where it's worth arguing about what mechanism led to our boat's hull having holes in it, or what could have been done to prevent this. We are at the point where we must be frantically bailing.
There are a few ways I can think of to combat the antibiotic resistant bacteria that threaten our wellbeing. I will list them below, with a summary of each. THESE SUMMARIES OMIT STEPS IN ORDER TO BE EASY TO UNDERSTAND! DO NOT ATTEMPT TO FOLLOW THEM VERBATIM WITHOUT ADDITIONAL READING.
Bacteriophages. Bacteriophages are viruses that target bacteria. The technique of using them to destroy pathogenic bacteria is called phage therapy. This technique was used before our modern antibiotics were discovered, and refined in the Soviet Union throughout the 20th century. Phage therapy is attractive because phages capable of destroying any given bacterium are likely present in the environment already, and substances such as dirt and seawater contain bacteriophages in high concentrations. To find a phage to destroy a given bacterium, you grow a culture plate of the target bacterium, and apply diluted [dirt, seawater, your substance of choice here]. If you see holes (called plaques) form in the culture, it is likely that you have found a phage that is capable of destroying your target bacterium. Then you grow a liquid culture of the target bacterium and add some of the material from the plaque in your culture plate to the liquid culture. Observation with a light microscope can confirm the lysing of the target bacterium. From such liquid cultures, you may refine phages that are active against the bacterium that is causing you problems. The major drawback of phage therapy is that you need to specifically match each phage to each pathogenic bacterium. However, it may be implemented using only primitive lab equipment and relatively unskilled technicians. Setting up phage labs in population centers is a high priority!
Resistance enzyme inhibitors. Many types of antibiotic resistance are conferred by enzymes that destroy the antibiotic agent in question. CRE (Carbapenem resistant enterobacteriaceae) gets its resistance to carbapenem from the enzyme carbapenemase. A substance that acted as a carbapenemase inhibitor would cause CRE to lose its resistance to carbapenem. Such inhibitors can be found for all antibiotic resistances that are mediated by enzymes that directly target the antibiotic agent.
Novel antibiotic agents. These may be variants of existing antibiotics or (probably better, since they'd buy us a little more time) completely novel antibiotic agents that may be used as the basis for new families of antibiotics. The first place we will be looking for these is in old research. Many compounds with antibacterial properties have been described, some of these are safe for humans to ingest, and only a tiny fraction were developed into widely-used antibiotics. Specifically, we should focus on compounds that were previously known for other uses and thus not possible to patent, as these will have been overlooked by our profit-motivated pharmeceutical companies.
Antiserum. Like bacteriophages, antisera were developed before our modern antibiotics. Here's a rough explanation of how to make them. Infect a creature with a bacterium. Assuming the creature survives the infection, you can then inject more of the bacterium into the creature in order to deliberately provoke an immune response. Extract the creature's blood, and centrifuge to obtain its blood serum, the blood component that contains antibodies. This blood serum can be injected into a different creature in order to temporarily confer immunity to the bacterium in question, or to combat an active infection.
Custom antibodies. Modern biology enables us to produce arbitrary custom antibodies. (I don't know the exact method of production. My skill area is electrical engineering, not biology.) These may be used as antisera would, but with a lower side-effect profile.