Project description:Bacterial small RNAs (sRNAs) regulate gene expression by base-pairing with downstream target mRNAs to attenuate translation of mRNA into protein at the post-transcriptional level. In response to specific environmental changes, sRNAs can modulate the expression levels of target genes, thus enabling adaptation of cellular physiology. We profiled sRNA expression in the Gram-negative bacteria Burkholderia thailandensis cultured under 54 distinct growth conditions using a Burkholderia-specific microarray that contains probe sets to all intergenic regions (IGRs) greater than 90 bases. We identified 38 novel sRNAs and performed experimental validation on five sRNAs that play a role in adaptation of Burkholderia to cell stressors.
Project description:Bacterial small RNAs (sRNAs) regulate gene expression by base-pairing with downstream target mRNAs to attenuate translation of mRNA into protein at the post-transcriptional level. In response to specific environmental changes, sRNAs can modulate the expression levels of target genes, thus enabling adaptation of cellular physiology. We profiled sRNA expression in the Gram-negative bacteria Burkholderia thailandensis cultured under 54 distinct growth conditions using a Burkholderia-specific microarray that contains probe sets to all intergenic regions (IGRs) greater than 90 bases. We identified 38 novel sRNAs and performed experimental validation on five sRNAs that play a role in adaptation of Burkholderia to cell stressors. A custom Affymetrix microarray was designed using Burkholderia thailandensis E264 gene annotations from Pathema and included 8711 probe sets targeting 5557 protein-coding genes and 2908 IGRs longer than 90 bases on the plus strand. Experiments were performed in four classes of media: nutrient broth, M9-minimal media, Luria broth, and various host conditions such as brain-heart infusion, calf serum, or tryptic soy broth. There were 101 samples in four time course arrays measuring temperature increase, pH drop, salt stress, and phosphate starvation (21 distinct conditions). Each condition was grown at 37° C, except the initial temperature experiment at 25°C, and replicated five times. In order to survey a diverse range of environmental and stress conditions, another 10 replicated and 23 unreplicated treatments were also tested.
Project description:The proteome of Burkholderia thailandensis E264 was assessed by shotgun proteomics as well as the proteome of the strain after quorum sensing disruption.
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.
