Location of Repository

The antibacterial properties of secreted phospholipases A(2) - A major physiological role for the group IIA enzyme that depends on the very high pI of the enzyme to allow penetration of the bacterial cell wall

By S.A. Beers, A.G. Buckland, R.S. Koduri, W. Cho, M.H. Gelb and D.C. Wilton


The antibacterial properties of human group IIA secreted phospholipase A(2) against Gram-positive bacteria as a result of membrane hydrolysis have been reported. Using Micrococcus luteus as a model system, we demonstrate the very high specificity of this human enzyme for such hydrolysis compared with the group IB, IIE, lIF, V, and X human secreted phospholipase A(2)s. A unique feature of the group IIA enzyme is its very high pI due to a large excess of cationic residues on the enzyme surface. The importance of this global positive charge in bacterial cell membrane hydrolysis and bacterial killing has been examined using charge reversal mutagenesis. The global positive charge on the enzyme surface allows penetration through the bacterial cell wall, thus allowing access of this enzyme to the cell membrane. Reduced bacterial killing was associated with the loss of positive charge and reduced cell membrane hydrolysis. All mutants were highly effective in hydrolyzing the bacterial membrane of cells in which the cell wall was permeabilized with lysozyme. These same overall characteristics were also seen with suspensions of Staphylococcus aureus and Listeria innocua, where cell membrane hydrolysis and antibacterial activity of human group IIA enzyme was also lost as a result of charge reversal mutagenesis

Topics: QH301
Year: 2001
OAI identifier: oai:eprints.soton.ac.uk:35566
Provided by: e-Prints Soton
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://dx.doi.org/10.1074/jbc.... (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.