Is it true that bacteria becoming resistant to drugs results from a loss of genetic information, not a gain in information?
Yes the research indicates that the resistance to antibiotics comes from a loss of genetic information, not a gain in information.
Page 261 The Beak of the Finch Jonathan Weiner The researchers found that in each strain of bacteria that had developed resistance to antibiotics the bacteria had dropped from its chromosomes a gene called
When the researchers artificially inserted this gene back into the genome the bacteria the bacteria was killed by the antibiotic.
..... page 261 Apparently the cells had paid a price to defend themselves from the drug. They had made an evolutionary tradeoff giving up part of their own adaptive equipment for the sake of survival. The bacillus got rid of an Achilles heel by evolving a heel-less foot.
All current research on bacteria resistance shows that bacteria evolve by losing genetic information, to respond and adapt to changes in the environment. There is no empirical evidence that mutations create new information that contribute to resistance to antibiotics.