Detection and characterization of 45 kDa platelet activating factor acetylhydrolase in cerebrospinal fluid of children with meningitis.
Platelet activating factor acetylhydrolase (PAF-AH) activity has been identified in cerebrospinal fluid (CSF) samples taken from children with meningitis. We reported that PAF-AH activity is significantly increased, by about 3 fold, in patients with meningitis compared to control subjects. Because of limited knowledge about this enzyme in CSF, we examined the biochemical properties of CSF PAF-AH. PAF-AH of CSF was calcium independent, showed a broad pH spectrum and was relatively heat stable. In addition, this enzyme activity was strongly inhibited by phenylmethanesulfonyl fluoride (PMSF), partially inhibited by p-bromophenacylbromide (p-BPB), uninhibited by iodoacetamide, and moderately stimulated by dithiothreitol (DTT). PAF-AH of CSF did not degrade phospholipid with a long chain fatty acyl group at sn-2 position. This enzyme hydrolyzed PAF and oxidatively modified phosphatidylcholine. Furthermore, we identified a monomeric polypeptide with a molecular weight of approximately 45 kDa by Western blot using human plasma PAF-AH antibody. These results suggested that plasma type PAF-AH activity exist in CSF taken from children with meningitis.
Moon
Tae Chul
TC
College of Pharmacy, Yeungnam University, Gyongsan 712-749, Korea.
Kim
Mi Suk
MS
Lee
Su Jeong
SJ
Lee
Tae Yoon
TY
Kwon
Soon Hak
SH
Baek
Suk Hwan
SH
Chang
Hyeun Wook
HW
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000037:antagonists & inhibitors / Q000134:cerebrospinal fluid*; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000134:cerebrospinal fluid; D008581:Meningitis / Q000134:cerebrospinal fluid* / Q000201:enzymology*
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase