Destabilization of phospholipid model membranes by YplA, a phospholipase A2 secreted by Yersinia enterocolitica.
Yersinia enterocolitica produces a virulence-associated phospholipase A(2) (YplA) that is secreted via its flagellar type-III secretion apparatus. When the N-terminal 59 amino acids of YplA are removed (giving YplA(S)), it retains phospholipase activity; however, it is altered with respect to the apparent kinetics of hydrolysis using fluorescent phospholipid substrates in micellar form. To explore the physical properties of YplA more carefully, Langmuir phospholipid monolayers were used to study the association of YplA with biological membranes. YPlA and YplA(S) both associate with Langmuir monolayers, but YplA(S) appears to interact better at low initial lipid densities while YplA interacts better at higher densities. This may indicate that the N-terminus of YplA has a role in mediating its initial interaction with compact cellular membranes, which is consistent with spectroscopic observations that fluorescein-labeled YplA may interact more readily with the nonpolar region of liposomes than does YplA(S).
Berring
Erin
E
Department of Chemistry, Saint Louis University, Monsanto Hall 125, 3501 Laclede Avenue, St. Louis, MO 63103-2010, USA.
Brancato
Sam
S
Grant
Katherine
K
Schaper
Elizabeth
E
Kadavil
Sheena
S
Smagin
Helen
H
Hatic
Safet O
SO
Picking
William
W
Serfis
Alexa Barnoski
AB
D005407:Flagella / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D010741:Phospholipases A / Q000378:metabolism*; D054467:Phospholipases A2; D010743:Phospholipids / Q000378:metabolism*; D015008:Yersinia enterocolitica / Q000201:enzymology*
D008081:Liposomes; D010743:Phospholipids; D010741:Phospholipases A; D054467:Phospholipases A2