Replication Dynamics for Six Gram-Negative Bacterial Species during Bloodstream Infection
Mark T. Anderson, Aric N. Brown, Ali Pirani, Sara N. Smith, Amanda Photenhauer, Yuang Sun, Evan S. Snitkin, Michael A. Bachman, Harry L. T. Mobley
Abstract
Bloodstream infections are a global public health problem. The goal of this work was to determine the replication characteristics of Gram-negative bacterial species in the host following bloodstream infection. The number of bacteria in major organs is likely determined by a balance between replication rates and the ability of the host to clear bacteria. We selected a cohort of six species from three families that represent common causative agents of bloodstream infections in humans and determined their replication rates in a murine bacteremia model. We found that the bacteria grow rapidly in the spleen, demonstrating that they can obtain the necessary nutrients for growth in this environment. However, the overall number of bacteria decreased in most cases, suggesting that killing of bacteria outpaces their growth. Through a better understanding of how bacteria replicate during bloodstream infections, we aim to gain insight into future means of combating these infections.