title: Bactericidal properties of human and murine groups I, II, V, X, and XII secreted phospholipases A(2).
abstract: Group IIA secreted phospholipase A(2) (sPLA2) is known to display potent Gram-positive bactericidal activity in vitro and in vivo. We have analyzed the bactericidal activity of the full set of recombinant murine and human groups I, II, V, X, and XII sPLA2s on Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli. The rank order potency among human sPLA2s against Gram-positive bacteria is group IIA > X > V > XII > IIE > IB, IIF (for murine sPLA2s: IIA > IID > V > IIE > IIC, X > IB, IIF), and only human group XII displays detectable bactericidal activity against the Gram-negative bacterium E. coli. These studies show that highly basic sPLA2s display potent bactericidal activity with the exception of the ability of the acidic human group X sPLA2 to kill Gram-positive bacteria. By studying the Bacillus subtilis and S. aureus bactericidal potencies of a large panel of human group IIA mutants in which basic residues were mutated to acidic residues, it was found that: 1) the overall positive charge of the sPLA2 is the dominant factor in dictating bactericidal potency; 2) basic residues on the putative membrane binding surface of the sPLA2 are modestly more important for bactericidal activity than are other basic residues; 3) relative bactericidal potency tracks well with the ability of these mutants to degrade phospholipids in the bacterial membrane; and 4) exposure of the bacterial membrane of Gram-positive bacteria by disruption of the cell wall dramatically reduces the negative effect of charge reversal mutagenesis on bactericidal potency.
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Rao S
authors.initials: RS
authors.lastname: Koduri
authors.forename: Juha O
authors.initials: JO
authors.lastname: Grönroos
authors.forename: Veli J O
authors.initials: VJ
authors.lastname: Laine
authors.forename: Catherine
authors.initials: C
authors.lastname: Le Calvez
authors.forename: Gérard
authors.initials: G
authors.lastname: Lambeau
authors.forename: Timo J
authors.initials: TJ
authors.lastname: Nevalainen
authors.forename: Michael H
authors.initials: MH
authors.lastname: Gelb
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects / Q000502:physiology; D004926:Escherichia coli / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D054501:Group II Phospholipases A2; D054505:Group V Phospholipases A2; D054509:Group X Phospholipases A2; D006801:Humans; D006868:Hydrolysis; D007527:Isoenzymes / Q000494:pharmacology; D008563:Membrane Lipids / Q000378:metabolism; D051379:Mice; D008826:Microbial Sensitivity Tests; D016297:Mutagenesis, Site-Directed; D010741:Phospholipases A / Q000494:pharmacology*; D010743:Phospholipids / Q000378:metabolism; D011523:Protoplasts / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D007527:Isoenzymes; D008563:Membrane Lipids; D010743:Phospholipids; D011994:Recombinant Proteins; D010741:Phospholipases A; D054501:Group II Phospholipases A2; D054505:Group V Phospholipases A2; D054509:Group X Phospholipases A2; C516365:PLA2G10 protein, human; C516293:PLA2G2D protein, human; C516299:PLA2G5 protein, human; C516366:Pla2g10 protein, mouse; C516300:Pla2g5 protein, mouse