15. The effect of freezing and thawing on phospholipids of glycerol mutants of Escherichia coli

Abstract

The effects of freezing and thawing on the cell envelope phospholipids of three glycerol mutants of Escherichia coli were determined when glycerol was absent, intracellular, extracellular or both intra- and extracellular. Loss of phospholipid was related to the rate of freezing. There was a greater loss of phospholipid with a fast rate of freezing than with a slow one.Intracellular glycerol appeared to prevent the breakdown and interconversion among phospholipid classes. Extracellular glycerol reduced the amount of phospholipid loss. Phosphatidylethanolamine accounted for nearly all of the phospholipid loss.