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Abstract: Burkholderia pseudomallei, the causative agent of the disease melioidosis is a human pathogen endemic in Northern Australia and South-East Asia. At present there is no available vaccine or effective treatment for this disease. Surface proteins play crucial roles in the host–pathogen interaction and have been exploited as vaccine candidates and diagnostic targets. Therefore, we wished to identify immunogenic surface proteins of B. pseudomallei. To this end we used two proteomic-based approaches in parallel: a biotinylation approach for the detection of surface located proteins identified 35 proteins, while screening with human sera identified 12 immunogenic proteins. Nine of these proteins were identified by both methods indicating that they may be both surface located and immunogenic: these proteins will be evaluated further as vaccine candidates and diagnostic targets. [Copyright &y& Elsevier]

Disulfiram (DSF) can help treat alcohol dependency by inhibiting aldehyde dehydrogenase (ALDH). Genomic analysis revealed that Francisella tularensis , the causative agent of tularemia, has lost all but one ALDH-like domain and that this domain retains the target of DSF. In this study, minimum inhibitory concentration (MIC) assays demonstrated that both DSF and its primary metabolite diethyldithiocarbamate (DDC) have strong antimicrobial activity against F. tularensis strain SCHU S4, with the MIC of DSF determined as 2 µg/mL in comparison with 8 µg/mL for DDC. The activity of DSF was further confirmed using an in vitro human macrophage infection assay. Francisella tularensis bacteria in DSF-treated cells were reduced in comparison with untreated and DDC-treated cells, comparable with that observed in doxycycline-treated cells. This suggests that DSF may be suitable for further investigation as an in vivo therapy for tularemia. [ABSTRACT FROM AUTHOR]

Highlights: [•] The utility of nasally delivered LL-37 as a post-exposure therapy for tularaemia in mice was examined. [•] Significant reduction in bacterial growth was seen in LVS infected macrophages treated with LL-37. [•] LL-37 stimulated increased neutrophil and pro-inflammatory chemokine and cytokine levels in the lung. [•] 3 doses of LL-37 significantly extended mean time to death of mice infected with F. tularensis LVS. [Copyright &y& Elsevier]

Abstract: Burkholderia thailandensis is a less virulent close relative of Burkholderia pseudomallei, a CDC category B biothreat agent. We have previously shown that lipopolysaccharide (LPS) extracted from B. pseudomallei can provide protection against a lethal challenge of B. pseudomallei in a mouse model of melioidosis. Sugar analysis on LPS from B. thailandensis strain E264 confirmed that this polysaccharide has a similar structure to LPS from B. pseudomallei. Mice were immunised with LPS from B. thailandensis or B. pseudomallei and challenged with a lethal dose of B. pseudomallei strain K96243. Similar protection levels were observed when either LPS was used as the immunogen. This data suggests that B. thailandensis LPS has the potential to be used as part of a subunit based vaccine against pathogenic B. pseudomallei. [ABSTRACT FROM AUTHOR]