Photo by the Suez Canal Authority. The massive Ever Given cargo ship, stuck across Egypt’s Suez Canal, is blocking all traffic (March 24, 2021). The small bulldozer is trying to unblock the vital waterway.
The meme was created by my supervisor/amateur meme producer, Dr. Rob Beiko of Dalhousie University
“Antibiotic use is futile in the face of massive gene sharing.”
Sharing is caring – a phrase we all have heard and used since we were little. For humans, sharing is a, hopefully, conscious decision to help others. What if I told you that said behaviour is also exhibited in a community of bacteria? (But maybe without the consciousness). Some genes can be shared across bacteria, not limited to the species boundaries. Wide transmission of genes can sometimes benefit the recipient and even promote survival. In other words, bacteria share genes which can potentially benefit their neighbours.
Several types of shared (or mobile) genes exist, and various mechanisms are used to transmit the genes. The process is known as horizontal gene transfer (HGT) or lateral gene transfer. As bacteria replicate asexually, meaning there is no combination of genes from two parents, the shuffling of genes via HGT with their neighbours is a big source of new genetic diversity and a major contributor to evolution.
In my previous blog (AMR – Why do we keep hearing about it?), I hinted that the real culprits of the antimicrobial resistance (AMR) crisis are the resistance-conferring genes that are being disseminated. AMR genes are notorious for their mobility (e.g., beta-lactamase enzyme encoding genes that inhibit antibiotics whose names end with –cillin). The mobility of AMR genes was already an occurrence in natural environments, but human-induced activities are fueling the spread of these genes as if they were funny memes on social media. And sometimes, like the memes, they get better and better in the hands of new hosts.
Many research projects, including mine, are trying to predict bacterial resistance or susceptibility to antibiotics. Being able to accurately foresee the resistance to antibiotics can help clinicians avoid prescribing ineffective drugs and move on to the next best option. It can streamline the treatment process, allow speedy recovery for the patients, and ultimately lesser costs for the hospital. Machine learning (ML) is one method of predicting AMR that is gaining popularity. Computer algorithms are used to learn bacterial genetic patterns and predict resistance against certain antibiotics. However, it is a challenging task because of the HGT of AMR genes that continuously mix up the genetic diversity, among other reasons. With the advent of whole-genome sequencing, where we extract the entire DNA sequence information of bacteria, we are now starting to see a breadth of genetic patterns from various environments and a better picture of how genes can be shuffled around.
I am fascinated with bacteria because of the ability of such tiny organisms with limited resources to defend themselves, persist, and evolve. The infection caused by pathogens, from the pathogen’s perspective, is just their way of overcoming hardships and trying to survive in a harsh environment. Bacteria will continue to share genes to persevere as species, and I cannot bring myself to hate on such generosity.
