...Many other antibiotics are based on small molecules that interrupting some metabolic process of bacteria. Bacteria develop resistance by making enzymes that will break down these small molecules once inside the cell. This new method attacks the outside of the cell directly, not something inside the cell. It wouldn't be impossible for bacteria to develop immunity to this, but it would be comparably very improbable.
It may be less probable, but not improbable. Bacteria are so abundant, reproduce so fast, and can have such high mutation rates that probability is almost always on their side. They also can develop resistance in many ways other than "making enzymes." The likelihood of them developing resistance is proportional to the selection acting on them. If we put this stuff everywhere, selection will be very strong. They will develop resistance.
Are you a virtual scientist if you work on a computer?
My suggestion would be to look at Bioinformatics. There is more money in that field now and a huge need for programmers. Also check http://www.nescent.org/ for an example of a broader effort to develop software to deal with rapidly growing large sequence and gene expression datasets to answer evolutionary questions. The hire people like you fairly often.