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Buchholtz, K.

Publications and source records attributed to Buchholtz, K..

2 recordsLinked to original sources

Chronic wounds and adaptive Pseudomonas aeruginosa: A phenotypic and genotypic characterization

Phenotypic and genetic diversity is found in varying prevalence in clinical populations where beneficial adaptations enable the bacteria to avoid recognition and eradication by the host immune system. This study aimed to investigate the presence of Pseudomonas aeruginosa in chronic venous leg ulcers wounds over an 8-week time course. This was performed using genomic and phenotypic approaches to understand the survival and persistence of Pseudomonas strains. The findings of this study show that the two patients were colonized with a recurring P. aeruginosa genotype with only minor phenotypic differences and few SNP differences, suggesting that the Pseudomonas isolates present in the wound can survive and proliferate in the hosts hostile environment. The results provided from this study will allow us to understand clinically important traits in P. aeruginosa and provide insight into the dynamics and adaptations (or the lack thereof) in chronic wounds. HighlightsO_LIEach patient is colonised overtime with a unique MLST C_LIO_LIThe total number of detected SNPs was 18 and 20 within each patient, respectively C_LIO_LIOne MLST belonged to the sequence type ST132, often observed in clinical isolates, whereas the other belonged to ST3244, previously seen inenvironmental isolates C_LI

microbiology↗

Analysis of antibiotic response in Clinical Wound Pseudomonas aeruginosa isolates: Unveiling Proteome Dynamics of tobramycin tolerant phenotype

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic human pathogen, causing serious chronic infections. P. aeruginosa can adapt efficiently to antibiotic stressors via different genotypic or phenotypic strategies such as resistance and tolerance. The adaptation regulatory system is not always very well understood. In this study, we use shotgun proteomics to investigate the system-level response to tobramycin in two clinical wound P. aeruginosa isolates and PAO1. We profiled each strain for its antibiotic drug-tolerant phenotype using supra-minimum inhibitory concentrations (supra-MIC) of tobramycin and applied proteomics to investigate the protein expression profiles. The MIC revealed that all isolates were susceptible to tobramycin but at supra-MIC concentrations at stationary growth, a degree of tolerance was observed for the isolates. We identified around 40 % of the total proteins encoded by the P. aeruginosa genome and highlighted shared and unique protein signatures for all isolates. Comparative proteome profiling in the absence of antibiotic treatment showed divergent fingerprints, despite similarities in the growth behavior of the isolates. In the presence of tobramycin, the isolates shared a common response in the downregulation of proteins involved in the two-component system, whereas stress response proteins were present at higher levels. Our findings provide insight into the use of proteomic tools to dissect the system-level response in clinical isolates in the absence and presence of antibiotic stress.

microbiology↗