Funding for this research was provided by:
National Institute of General Medical Sciences (GM114471, GM072295)
Received: 18 January 2018
Accepted: 18 April 2018
First Online: 27 April 2018
: M.M. and J.N.B. are at the Department of Biochemistry & Cellular and Molecular Biology at the University of Tennessee, Knoxville. I.B.Z. holds appointments at the Department of Microbiology at the University of Tennessee, Knoxville as well as at the Division of Computational Sciences and Engineering, Oak Ridge National Laboratory, Oak Ridge, TN.
: Not applicable.
: The authors declare that they have no competing interests.