Figure 1. Excess glucose promotes cell death in S. aureus.
(A) S. aureus UAMS-1 cell viabilities (cfu/ml, mean ± SD) were monitored every 24 h over a period of five days in TSB-14 mM or TSB-35 mM glucose. (*) indicates time-points when samples were withdrawn for flow cytometry and electron paramagnetic resonance spectroscopy (EPR) analysis. (B) Psuedocolor density plots of cells double stained with HPF and CTC. (C) Oxygen consumption rates were determined using a commercially available kit (* P<0.05, Students t-test, n = 2) (D) Whole cell EPR analysis of S. aureus undergoing programmed cell death (PCD) was carried out after 72 h growth. (E) TUNEL staining of 1% paraformaldehyde fixed cells was performed using the ApoDirect kit (Millipore) and analyzed by flow cytometry. Gates were based on 24 h cultures that exhibited minimal loss in cell viability.