You read it again. I minored in evolutionary theory in pre-med. I understand the supposed mechanism quite well.
a spontaneous mutation in the bacterial chromosome imparts resistance to a member of the bacterial population.
This is the theory. For instance, most gram positive bacteria such as Staph Aureus have a gene for an inducible beta-lactamase. Use of penicillins induced the expression of this beta lactamase. So researchers added a sulbactim to drugs such as Augmentin and Unisyn to fake out the beta-lactamase so the penicillin derivative drug to still kill the bug. However, strep strains do not possess a beta lactamase, and thus the penicillins are still the DOC for strep throat.
But again, this is a pre-existing DNA sequence. It is not a spontaneous mutation in the bacterial chromosome.
I'm asking for a specific example of a spontaneous mutation in the bacterial chromosome itself, not a theory about vertical evolution. Its easy to claim it in theory. Proving it in practice is a little different.
By the way, I am not a creationism nor an intelligent design advocate. But I have had enough evoltionary and micro bio and organic bio courses to admit there are major problems in Darwinian evolutionary claims.
I did a quick medline search using 'mutation evolution antibiotic resistance'. I came up with 32 hits, including an extensive series of papers on the TEM beta lactamase, in which it was shown both in vitro and in vivo that antibiotic resistance to cefotaxime, cefuroxime, ceftazadime, and aztreonam evolved by single amino-acid substitutions from an ancestral penicillinase gene. The authors conclusion (and I quote) "The authors take this result as evidence that their in vitro evolution technique accurately mimics natural evolution and can therefore be used to predict the results of natural evolutionary processes. "
Predicting evolutionary potential: In vitro evolution accurately reproduces natural evolution of the TEM b-lactamase. Barlow, Miriam; Hall, Barry G. Biology Department, University of Rochester, Rochester, NY, USA. Genetics (2002), 160(3), 823-832.
I can post lots more refs and abstracts if you like. I have no idea what else you think vertical evolution might be; no one is suggesting antibiotic resistance involves production of a de novo protein; it's nearly always going to be by modification of an existing enzyme activity.