Evolutionary theory kills: revisited

Epidemic of Escherichia coli infections traced to one strain of bacteria

Excerpt: By gaining mutations in two genes, a strain called H30 gave rise more than a decade ago to the H30-R clone, which became fully resistant to the then-wonder-drug known as Cipro. Soon after, a new clone evolved from H30-R called H30-Rx, which is resistant to several extended-spectrum antibiotics, such as third-generation cephalosporins.

My comment: In my model, the H30 strain gave rise to the H30-R clone via adaptations, not by gaining mutations. The initial strain adapted to the thermodynamic challenge of maintaining its nutrient-dependent pheromone-controlled organism-level thermoregulation, which was required for it to adapt to changes in the cell wall caused by the antibiotic.

Adaptations must continue to occur, when new antibiotics are introduced. Nutrient-dependent alternative splicings continue to enable organisms to better tolerate the increased body temperature associated with “fever” in humans. Nutrient-dependent changes in the epigenetic landscape of the bacteria enable the physical landscape of  DNA in its organized genome to incorporate pheromone-controlled epigentically-effected alternative splicings that increase the thermodynamic stability of the cell type. The increased thermodynamic stability of the unicellular cell type may enable it to overtake the immune system defenses of any organism that would otherwise kill it via an increase in body temperature.  However,  an adapted strain of what once was a non-pathogen associated with the metabolism of nutrients may become a killer in immuno-compromised patients, like those who are hospitalized with infections.

However, Randy Nesse addressed a larger problem (in a lecture I attended last August) that may be responsible for part of the problem with infections in immuno-compromised patients. Prescription antibiotics typically may not be required to kill a pathogen that is causing an uncomfortable fever in a patient. Antibiotic use may relieve their discomfort and reduce the fever by killing most but not all of the organism that is causing the problem. Later in life, patients succumb to strains of the organism with increased organism-level thermoregulatory capacity that has developed due to past antibiotic use. I discussed that fact in this video of the poster presentation I made at that conference.

 

Mutations perturb: evolutionary theory kills

Author: James Kohl

Leave a Reply

Your email address will not be published.