PubMed · 2755487
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
J Mowles, S Moran, A Doyle. 1989-08-03. Mycoplasma control.. https://doi.org/10.1038/340352c0
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Methicillin-resistant Staphylococcus aureus (MRSA) is a globally significant pathogen causing severe infections. The chronicity and recurrence of its infection pose serious challenges to public health. In this study, we reported that intracellular accumulation of α-ketoglutarate (α-KG) significantly increased ciprofloxacin (CIP) tolerance in MRSA. Using integrated metabolomic and functional genomic approaches, we demonstrated that both exogenous α-KG and genetic knockout of α-KG dehydrogenase (ΔsucA, ΔsucB) induced CIP tolerance in MRSA. Mechanistically, elevated α-KG levels drive the accumulation of glutamate (Glu), which in turn reduced bacterial membrane potential and cellular ATP content. Furthermore, Glu accumulation raised intracellular osmotic pressure, leading to decreased CIP uptake. These metabolic alterations enable MRSA to sustain high tolerance toward ciprofloxacin. Our findings reveal a key role of the α-KG-Glu metabolic axis in driving antibiotic tolerance and provide novel insights into the metabolic adaptations underlying drug persistence in MRSA.
Explore the source record for details and available documents.
Viable but non-culturable transconjugant cells were detected by a modification of the direct viable count (DVC) method. This modification involved the addition of parental antimicrobial markers (kanamycin and streptomycin) to the elongation medium in order to promote selective elongation of the transconjugant cells. Presence of viable, other than culturable, transconjugants was demonstrated in matings with parental cells from TSB culture as well as with recipient cells from survival in river water (under illuminated and non-illuminated systems). In matings with a recipient strain from illuminated systems, culturable transconjugants were not detected after the third day of recipient cell survival. In spite of this, viable transconjugants were detected in numbers that exceeded 10(5) cells ml-1. These results clearly show that a fraction of non-culturable recipient cells is able to receive and express plasmids by conjugation processes and form viable but non-culturable transconjugant cells.