The Evolutionary Sequence of the Anthrax Toxins Carolyn Vanek The Evolutionary Sequence of the Anthrax Toxins

Anthrax: Background Routes of Infection: Skin Lung Intestines Spores can stay in the ground for decades Herbivores eat something containing the spores, they become infected, infection is passed on 2000 cases per year, 2 in the US Respiratory anthrax has 50-80% mortality rate with treatment

The Three Horsemen of the Apocolypse Protective Antigen Edema Factor Lethal Factor Death Edema Death LF not toxic by itself Nothing

Protective Antigen Needed for internalization

Edema Factor Calmodulin-sensitive adenylate cyclase Provokes dramatic elevation of intracellular cAMP levels in the host Needs calmodulin to be active

Lethal Factor t is a protease that cleaves the N-terminal of most dual specificity mitogen-activated protein kinase kinases (MAPKKs or MAP2Ks)

Question: What can phylogenetic analysis show about Anthrax’s inheritance of these three proteins?

Sequence Obtained from NCBI BLOSUM50 Matrix Targets alignments with 20-30% Identity Depending on sequence, retrieve 70-1000 sequences Removed repeated and hypothetical proteins Manual curation Final alignments had anywhere from 12-50 proteins Matrix because not that many poisons (thank god) so looking for larger evolutionary differences Looked at Orthologs primarily Max Expect value of 1 Frequently found one of the EF in PA. Early indication of duplications

Side Note: Lethal Factor

Sequence Alignment Used Tcoffee, default Tcoffee best but slowest Few sequences in analysis

Tree Creation Divergent sequences were frequently an issue Used Observed over Poisson Tested Including Gaps and Ignoring Gaps Including Gaps gave better bootstrap on trees Trees also made more sense in the way proteins were grouped