Bakteria dormancy is survival strategy in response to stressful exposure to antibiotics taken by a patient for treatment. The dormant cells become tolerant to antibiotics and are killed at slower rate and survive sometimes. This is called ‘antibiotic tolerance’ which is unlike antibiotic resistance when vimelea grow in the presence of antibiotics. Chronic or relapsing infections are attributed to antibiotic tolerance, for which there is no effective treatment. Phage therapy has long been considered but the dormant bacterial cells are non-responsive and refractory to known bacteriophages. Scientists of ETH Zurich have identified a new bacteriophage that uniquely replicates on deep stationary-phase cultures of Pseudomonas aeruginosa. Named ‘Paride’, this bacteriophage could kill deep-dormant P. aeruginosa by direct lytic replication. Interestingly, this novel phage reduced bacterial loads through phage-antibiotic synergy when meropenem antibiotic was added to cultures. Apparently, the novel phage could exploit weak spots in the physiology of dormant bacteria to overcome antibiotic tolerance. These weak spots could be targets of new treatment for chronic infections caused by dormant or inactive bacteria.
Most bacteria on Earth are in dormant state of reduced metabolic activity or in completely inactive form of spore. Such bakteria cells can be readily resuscitated when required nutrients and molecules become available.
Bakteria dormancy or inactivity is the survival strategy in response to stressful external environmental conditions like starvation or exposure to antibiotics taken by a patient for treatment. In later case, the dormant cells become tolerant to antibiotics because cellular processes targeted by the antibiotics to kill vimelea are turned down. This phenomenon is called ‘uvumilivu wa antibiotic' katika hali ambayo bakteria huuawa kwa kasi ya polepole na kuishi wakati mwingine (tofauti na kesi ya upinzani wa antibiotic wakati bakteria inakua mbele ya antibiotics). Maambukizi sugu au yanayorudi tena yanahusishwa na seli za bakteria zinazostahimili viuavijasumu, ambazo mara nyingi huitwa "zinaendelea", ambazo hakuna matibabu madhubuti.
Phage therapy involving bacteriophages or phages (i.e., virusi that predate vimelea), has long been considered for treating chronic infections by dormant or inactive vimelea however this approach works when host bakteria cells are undergoing growth. The dormant or inactive bakteria cells, however, are non-responsive and refractory to the bacteriophages which either avoid adsorption to the bakteria cell surfaces or hibernate in the dormant cells until resuscitation.
Known bacteriophages do not have ability to infect antibiotic-tolerant, deep-dormant or inactive vimelea. It was thought that given diversity, phages with ability to infect dormant cells may exist in nature. Researchers have now identified one such novel bacteriophage for the first time.
Katika utafiti uliochapishwa hivi karibuni, wanasayansi wa ETH Zurich ripoti ya kutengwa kwa bacteriophage mpya ambayo inaiga kipekee juu ya tamaduni za awamu ya stationary. Pseudomonas aeruginosa katika maabara. Wameita bacteriophage hii Paride. Fagio hili linaweza kuua mtu aliyelala sana P. aeruginosa kwa urudufu wa moja kwa moja wa lytic. Jambo la kufurahisha ni kwamba, fagio hili la riwaya lilipunguza mizigo ya bakteria kupitia ushirikiano wa dawa za kuua viuavijasumu wakati kiuavijasumu cha meropenem kilipoongezwa. P. aeruginosa-tamaduni za fagio.
Inavyoonekana, fagio la riwaya linaweza kutumia matangazo dhaifu katika fiziolojia ya bakteria zilizolala ili kushinda uvumilivu wa viuavijasumu. Maeneo haya dhaifu yanaweza kuwa shabaha ya matibabu mapya ya maambukizo sugu yanayosababishwa na bakteria waliolala au wasiofanya kazi.
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Reference:
- Maffei, E., Woischnig, AK., Burkolter, MR et al. Phage Paride inaweza kuua seli tulivu, zinazostahimili viua vijasumu za Pseudomonas aeruginosa kwa urudufishaji wa moja kwa moja wa lytic. Nat Commun 15, 175 (2024). https://doi.org/10.1038/s41467-023-44157-3
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