Project description:Nosocomial outbreaks of infections caused by multidrug-resistant Acinetobacter baumannii have emerged as a serious threat to human health. The phosphoproteomics of pathogenic bacteria have been investigated for their role in virulence regulation networks. In this study, we analyzed the phosphoproteomics of two clinical isolates of A. baumannii: imipenem-sensitive strain SK17-S and -resistant strain SK17-R.
Project description:Using Nanopore sequencing, our study has revealed a close correlation between genomic methylation levels and antibiotic resistance rates in Acinetobacter Baumannii. Specifically, the combined genome-wide DNA methylome and transcriptome analysis revealed the first epigenetic-based antibiotic-resistance mechanism in A. baumannii. Our findings suggest that the precise location of methylation sites along the chromosome could provide new diagnostic markers and drug targets to improve the management of multidrug-resistant A. baumannii infections.
Project description:Objectives: Colistin remains a last-line treatment for multidrug-resistant Acinetobacter baumannii and combined use of colistin and carbapenems has shown synergistic effects against multidrug-resistant strains. In order to understand the bacterial responses to these antibiotics we analysed the transcriptome of A. baumannii following exposure to each.
Project description:Acinetobacter baumannii is an emerging nosocomial pathogen that causes severe infections such as pneumonia or blood stream infections. As the incidence of multidrug-resistant A. baumannii infections in intensive care units increases, the pathogen is considered of greater clinical concern. Little is known about the molecular interaction of A. baumannii with its host yet. In order to study the host cell response upon A. baumannii infection, a complexome analysis was performed. For this, we identified a virulent ( A. baumannii 2778) and a non virulent (A. baumannii 1372) clinical isolate of genetic similarity > 95 % (both isolates from IC 2 harboring OXA 23). HUVECs were infected with each strain and enriched mitochondrial fraction was used for complexome profiling. Complexome analysis identified dramatic reduction of mitochondrial protein complexes in the strain of greater virulence.
Project description:Acinetobacter baumannii is a major cause of nosocomial infections which can survive in different hospital environments and its multidrug-resistant capacity is major concern now-a-days. ppGpp dependent stringent response mediates reprogramming of gene expression with diverse function in many bacteria. A baumannii A1S_0579 gene is responsible for ppGpp production. Transcriptome analysis of early stationary phase cultures represents several differentially expressed genes in ppGpp deficient strain (∆A1S_0579). We found that the expression of csu operon, which is important in pili biosynthesis for early biofilm formation, was significantly reduced in the ppGpp-deficient strain. Our findings showed that ppGpp signaling plays critical role in biofilm formation, surface motility, adherence and virulence of A baumannii. This study is the first demonstration of the association between ppGpp and pathogenicity of A. baumannii.
Project description:Transcriptomics by RNA-seq provides unparalleled insight into bacterial gene expression networks, enabling a deeper understanding of the regulation of pathogenicity, mechanisms of antimicrobial resistance, metabolism, and other cellular processes. Here we present the transcriptome architecture of Acinetobacter baumannii ATCC 17978, a species emerging as a leading cause of antimicrobial resistant nosocomial infections. Differential RNA-seq (dRNA-seq) examination of model strain ATCC 17978 in 16 laboratory conditions identified 3731 transcriptional start sites (TSS), and 110 small RNAs, including the first identification of 22 sRNA encoded at the 3′ end of mRNA.
