Microbiology & Infectious Diseases
Davis RW 4th, Brannen A, Hossain MJ, Monsma S, Bock PE, Nahrendorf M, Mead D, Lodes M, Liles MR, Panizzi P. 2016. Complete genome of Staphylococcus aureus Tager 104 provides evidence of its relation to modern systemic hospital-acquired strains. 17:179
Davis RW 4th, Eggleston H, Johnson F, Nahrendorf M, Bock PE, Peterson T, Panizzi P. 2015. In Vivo Tracking of Streptococcal Infections of Subcutaneous Origins in a Murine Model. Molecular Imaging and Biology. 17(6):793-801
Davis R, Hossain MJ, Liles MR, Panizzi P. 2013. Complete Genome Sequence of Staphylococcus aureus Tager 104, a Sequence Type 49 Ancestor. Genome Announc. 1(5):e00706-13
More information to be provided shortly.
In this paper, we sought to track the progression of a subcutaneous infection of Streptococcus pyogenes from the initial site of injection to foci throughout the animal. To do so, we utilized the S. pyogenes strain Xen20, which is genetically modified to produce light using the bacterial luciferase enzyme. We demonstrate that the bioluminescent imaging did not show bacteria in any tissue outside the site of injection. However, more classical approaches, such as histology and microbiology, demonstrated sepsis and widespread bacterial foci in the spleen, liver, and other tissue.
Therefore, we began outlining the mechanism by which luciferase activity was being attenuated inside the tissue. Our initial indications seemed to demonstrate it may owe to the carbon substrates available in the tissue, and the specific metabolic pathways of S. pyogenes.
In this paper, we describe the construction of the Staphylococcus aureus Tager 104 genome. This strain was isolated in 1947, and therefore may serve as a "time capsule" of Staphylococcus aureus virulence factors. Previous work with this strain had demonstrated its ability to form vegetations on the heart valve in a murine model.
One particular challenge in this publication was finding the best way to assemble the genome to create a semi-automated pipeline which produced the best results. I utilized resources such as Linux Ubuntu and the Alabama Supercomputer in order to test various assembly programs and the order these programs are used in order to overcome the challenges of collapsed contigs and heavy repeat regions intrinsic to Staphylococcal genomes. The result was a combinatorial pipeline which utilizes both PacBio RS and Illumina MiSeq technologies, and varies in many ways from that previously suggested for hybrid assembly, which were found to be ineffective for the Tager 104 genome.
More information will be posted shortly.