Burkholderia pseudomallei is a saprophytic soil bacterium and the etiological agent that causes melioidosis. It is naturally resistant to many antibiotics and therefore is difficult to treat. Bacteriophages may provide an alternative source of treatment. We have isolated and characterised the bacteriophage ΦBp-AMP1. The phage is a member of the Podoviridae family and has a genome size of ~ 45 Kb. Molecular data based on the gene which encodes for the phage tail tubular protein suggests that the phage is distinct from known phages but related to phages which infect B. thailandensis and Ralstonia spp. The phage ΦBp-AMP1 is the first B. pseudomallei podovirus to be isolated from the environment rather than being induced from a bacterial culture. It has a broad host range within B. pseudomallei and can infect all 11 strains that we tested it on but not related Burkholderia species. It is heat stable for 8 h at 50°C but not stable at 60°C. It may potentially be a useful tool to treat or diagnose B. pseudomallei infections as it can lyse several strains of clinical relevance.

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Osteogenesis imperfecta (OI) is mainly characterized by bone fragility and Ehlers-Danlos syndrome (EDS) by connective tissue defects. Mutations in COL1A1 or COL1A2 can lead to both syndromes. OI/EDS overlap syndrome is mostly caused by helical mutations near the amino-proteinase cleavage site of type I procollagen. In this study, we identified a Thai patient having OI type III, EDS, brachydactyly, and dentinogenesis imperfecta. His dentition showed delayed eruption, early exfoliation, and severe malocclusion. For the first time, ultrastructural analysis of the tooth affected with OI/EDS showed that the tooth had enamel inversion, bone-like dentin, loss of dentinal tubules, and reduction in hardness and elasticity, suggesting severe developmental disturbance. These severe dental defects have never been reported in OI or EDS. Exome sequencing identified a novel de novo heterozygous glycine substitution, c.3296G > A, p.Gly1099Glu, in exon 49 of COL1A2 . Three patients with mutations in the exon 49 of COL1A2 were previously reported to have OI with brachydactyly and intracranial hemorrhage. Notably, two of these three patients did not show hyperextensible joints and hypermobile skin, while our patient at the age of 5 years had not developed intracranial hemorrhage. Here, we demonstrate that the novel glycine substitution in the carboxyl region of alpha2(I) collagen triple helix leads to OI/EDS with brachydactyly and severe tooth defects, expanding the genotypic and phenotypic spectra of OI/EDS overlap syndrome.

This study for the first time demonstrates that the PITX2 mutation could lead to non-syndromic orodental anomalies in humans. We propose that the specific location in the C-terminal domain of PITX2 is exclusively necessary for tooth development.