Project description:Based on rangewide sampling and three mitochondrial and two nuclear markers (together up to 1,850 bp and 1,840 bp, respectively), we examine the phylogeography of two helmeted terrapin species (Pelomedusa galeata and P. subrufa sensu stricto) and infer shifts of climatically suitable spaces since the Last Glacial Maximum using a modeling approach. Whilst P. galeata displays significant phylogeographic structuring across its range and consists of two deeply divergent lineages that could represent distinct species, P. subrufa shows no obvious phylogeographic differentiation. This seems to be related to historically stable or fluctuating ranges. One of the lineages within P. galeata appears to be confined to the westernmost, winter-rainfall region of South Africa and deserves special conservational attention due to the scarcity of surface water. The other lineage is distributed further east and is differentiated in three weakly supported subclades with parapatric distribution; one occurring inland, and two along the south and east coasts, respectively. As far as is known, P. subrufa occurs in South Africa only in the northeast of the country (Limpopo, Mpumalanga) and we report the species for the first time from the Lapalala Wilderness Area in the Waterberg region (Limpopo), approximately 350 km further west than previously recorded. We confirmed the occurrence of P. galeata only 80 km south of Lapalala. Thus, a sympatric occurrence of P. galeata and P. subrufa is possible. Another putative contact zone, for the two lineages within P. galeata, must be located in the Western Cape region, and further contact zones are likely for the eastern subclades within P. galeata. The nuclear loci provided no evidence for gene flow across taxa or genetic clusters within taxa. Future investigations should use denser sampling from putative contact zones and more nuclear markers to re-examine this situation. Despite few phylogeographic studies published for southern African biota, it seems likely that differentiation follows general rules, and that climate and physiographic barriers (e.g., the Great Escarpment) have shaped phylogeographic patterns.
Project description:We describe the first clinical isolate of Bordetella petrii from a patient with mandibular osteomyelitis. The only previously documented isolation of B. petrii occurred after the initial culture of a single strain from an environmental source.
Project description:Vibrio parahaemolyticus is the leading cause of seafood-borne infections in the United States. We report complete genome sequences for two V. parahaemolyticus strains isolated in 2007, CDC_K4557 and FDA_R31 of clinical and oyster origin, respectively. These two sequences might assist in the investigation of differential virulence of this organism.
Project description:ETEC is an important human pathogen. Although the mechanism of diarrhea is known in ETEC, the regulatory networks are less understood. This study was conducted to understand the global expression of ETEC isolate E24377A under different growth and environemental conditions. ETEC isolate E24377A was grown in the presence of several chemical signals, including bile salts, glucose, and pre-conditioned media (PCM) from other enteric pathogens. E24377A was also grown to different densities, to see if a quorum sensing mechanism was in place