Project description:Introduction. Burkholderia thailandensis is a clinically rare opportunistic pathogen in the genus Burkholderia, and the genomic features and virulence characteristics of B. thailandensis strains that cause human infection remain unclear.Gap Statement. B. thailandensis strains with different virulence induce different host innate immune responses in vitro.Aim. This work aimed to understand the sequence diversity, phylogenetic relationship, and virulence of B. thailandensis BPM causing human infection.Methodology. The comparative molecular and genomic analyses, and mouse infection studies were applied to analyse the virulence and genomic features of B. thailandensis BPM originating from China.Results. The whole genome sequence analysis showed that the genomes of BPM and other avirulent B. thailandensis strains were broadly similar, comprising two highly syntenic chromosomes with comparable numbers of coding regions (CDs), protein family distributions, and horizontally acquired genomic islands. By examining species-specific genomic regions, we obtained molecular explanations for previously known differences in virulence and discovered the potential specific virulence-associated genes of BPM, which likely work together to confer the virulence of BPM. Significantly reduced LD50 and survival rates during mouse infection experiments were found in BPM compared to the avirulent B. thailandensis E264 (BtE264).Conclusion. Taken together, the results of this study provide basic information on the genomic features and virulence characteristics of the virulent B. thailandensis strain BPM, which is helpful for understanding its evolution as it relates to pathogenesis and environmental adaptability.
Project description:Total transcript amplification (TTA) from single eukaryotic cells for transcriptome analysis is established, but TTA from a single prokaryotic cell presents additional challenges with much less starting material and lack of poly(A)-tails. We described, here, a novel method for single bacterium TTA, using a Burkholderia thailandensis model exposed to subinhibitory concentration of the antibacterial agent, glyphosate. Utilizing B. thialandensis microarray to assess the TTA method showed little gene bias (< 2 fold-change) and absence (~5-6%) when compared to the larger scale non-amplified RNA samples. B. thailandensis genes important to possibly recuperate and balance the intracellular amino acid pool were induced (or repressed) by the aromatic amino acid biosynthesis inhibitor, glyphosate. We validated our single-cell microarray data at the multi-cells and single-cell levels with lacZ and gfp reporter-gene fusions, respectively. This novel method will rejuvenate and expand the prokaryotic transcriptomic field. Two identical cultures of B. thailandensis wildtype strain E264 were grown in 1x M9 minimal medium supplemented with 1% Brij-58 and 20 mM glucose (MG) to mid-log phase. One culture was induced by final concentration of 0.01% (w/v) glyphosate for 30 minutes. Total RNA was then purified from B. thailandensis uninduced and induced samples, converted to cDNA and hybridized onto B. thailandensis 70mer triplicate array