Bacteria “Remember” with Iron: Unlocking Secrets to Fight Infections

Memory is typically associated with higher organisms. However, a recent investigation undertaken by scholars at the University of Texas at Austin has revealed that notwithstanding the absence of neurons, synapses, and nervous systems, when myriad bacteria congregate upon a common substrate, they can engender a phenomenon akin to memory. This encompasses coordinating activities such as collective swimming and the formation of biofilms, thereby endowing bacteria with the capacity to transmit these “memories” to subsequent generations. Subsequent scrutiny divulged that seemingly mundane iron played a pivotal role in the formation of this bacterial “memory.” Corresponding research papers have been disseminated in the Proceedings of the National Academy of Sciences.

Do bacteria genuinely possess the capability to formulate a “memory” and transmit it to progeny? Fu Yu, a savant at the State Key Laboratory of Microbial Resource Development at the Institute of Microbiology, Chinese Academy of Sciences, elucidated to a correspondent from Science and Technology Daily: “Strictly speaking, the bacterial ‘memory’ delineated in the University of Texas at Austin study does not pertain to biology per se. Rather, it denotes the bacterial response to external stimuli predicated upon alterations in iron concentration. This adaptation enables bacteria to thrive and proliferate more efficaciously in intricate environments.”

“The recent findings furnish valuable insights into combating bacterial resistance. By modulating iron concentrations artificially, we may attenuate bacterial adhesion at infection sites, diminish bacterial tolerance to antibiotics, augment the immune system’s capacity to eradicate pathogenic bacteria, and enhance the efficacy of antibiotic treatments,” underscored Fu Yu.

Tie is among the unsung heroes in this narrative.

Higher organisms, including Homo sapiens, possess the faculty of memory, facilitating continual adaptation to environmental vicissitudes and swift, accurate responses. Research postulates that this mnemonic ability originates within neural tissue. Neural tissue elicits nerve impulses subsequent to external stimulation, engendering conditioned reflexes towards specific stimuli and enabling appropriate responses upon subsequent encounters.

Fu Yu expounded: “Although bacteria lack brains and cannot retain information akin to higher organisms, they do exhibit a mechanism akin to ‘memory.’ This mechanism manifests chiefly in their adaptability to environmental flux and the transmission of genetic information and chemical substances.”

Bacteria possess the capacity to assimilate environmental cues. Frequent encounters with specific environments can confer an advantage upon bacteria, prompting the storage and rapid retrieval of pertinent information.

The latest inquiry, spearheaded by Suvik Bhattacharya and his team at the University of Texas at Austin, has demonstrated that bacteria not only harbor “memories” but also transmit these “memories” to succeeding generations.

Previously, researchers observed that bacteria with prior experience in swarming motility exhibit a proclivity towards collective movement. Bhattacharya and his cohorts sought to elucidate the underlying mechanisms driving this phenomenon. To this end, they devised an experimental apparatus capable of monitoring the movement of swarms comprising over 10,000 Escherichia coli cells. A suite of analyses revealed that these E. coli can retain the “memory” of swarm formation for up to four generations, transmitting it to their “great-grandchildren,” which persists until the seventh generation.

How, then, is this “memory” preserved and transmitted? The answer lies in iron. Iron, abundant in terrestrial environs, played a pivotal role in cellular processes during the nascent stages of Earth’s evolution, pre-dating the advent of oxygen in the atmosphere.

Bhattacharya expounded that the aforementioned “memory” mechanism of E. coli is contingent upon fluctuations in intracellular iron content. Their observations unveiled variance in iron levels among bacteria, crucial for cellular metabolism. E. coli evincing lower iron content tend towards collective movement, while those with elevated intracellular iron content tend to adhere in situ and form biofilms. Descendants inherit materials from parental cells, thereby perpetuating the “memory” of swarm movements.

Researchers posit that diminished iron levels prompt bacteria to assemble swiftly into motile groups scouring the environment for iron, while elevated iron levels prompt attachment and biofilm formation.

Their latest research further delineated that manipulating iron content in E. coli cells can modulate the duration of “memory” retention.

Fu Yu contends that iron, as a vital element in biological processes, exerts a profound influence on bacterial biochemistry. Hence, it is unsurprising that fluctuations in iron concentration regulate bacterial responses to the external milieu.

Bhattacharya contends that bacteria retain a “memory” dictating when to swarm and when to form biofilms, a trait with potential implications for human infection. Consequently, these findings assume paramount significance in the treatment and prevention of bacterial infections and the fight against antibiotic resistance. Bhattacharya stresses that iron concentration constitutes a prime target in treating bacterial infections, given its pivotal role in determining bacterial virulence.

Fu Yu expounded: “Elevated iron concentrations induce E. coli to cease motility and foster biofilm formation, heightening bacterial resistance. Conversely, diminished iron concentrations impede biofilm formation and exacerbate susceptibility to antibiotics. These insights offer guidance in tackling bacterial resistance, affording avenues to impede biofilm formation and mitigate antibiotic resistance, thus efficaciously combating infections.”

“The ‘memory’ evinced by microorganisms may stem from diverse mechanisms; nonetheless, fundamentally, these mechanisms represent microbial adaptations to long-term environmental shifts. Small though they may be, bacteria exhibit remarkable sagacity, promising a plethora of intriguing phenomena awaiting diligent scientific inquiry,” Fu Yu concluded.

error: Content is protected !!