Impact of high pressure freezing on DH5alpha Escherichia coli and red blood cells.
The impact of high pressure and freezing on survivability of Escherichia coli and human red blood cells was evaluated to determine the utility of high-pressure transitions for preserving living cells. Based on microscopy and survivability, high pressures did not directly impact physical damage to living cells. E. coli studies showed that increased cell death is due to indirect phenomena with decreasing survivability at increasingly high pressures and exposure times. Pressurization rates up to 1.4kbar/min had negligible effects relative to exposures of >5min at high pressures.Both glycine and control of pH near 7.0 were successful in reducing the adverse impacts of high pressure. Survivability increased from <1% at 5min exposure to 2.1kbar of pressure to typical values >20%. The combination of glycine and the buffer salt led to even further improvements in survivability. Pressure changes were used to traverse temperature and pressures consistent with Ice I and Ice III phase boundaries of pure water.
Suppes
Galen J
GJ
Department of Chemical Engineering, University of Missouri, W2028 EBE, 65211, Columbia, MO, USA. suppesg@missouri.edu
Egan
Susan
S
Casillan
Alfred J
AJ
Wei Chan
Kok
K
Seckar
Bill
B
D002021:Buffers; D002470:Cell Survival; D003080:Cold Temperature; D015925:Cryopreservation / Q000379:methods*; D004912:Erythrocytes / Q000166:cytology* / Q000502:physiology; D004926:Escherichia coli / Q000166:cytology* / Q000502:physiology; D005615:Freezing; D005998:Glycine / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007053:Ice; D011312:Pressure; D012492:Salts / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors; D014867:Water
D002021:Buffers; D007053:Ice; D012492:Salts; D014867:Water; D005998:Glycine