|
|
||||||||
Journal of Lipid Research, Vol. 43, 1114-1124, July 2002
Copyright © 2002 by Lipid Research, Inc.



* Department of Chemistry, State University of New York, ESF, Syracuse, NY 13210
Department of Microbiology & Immunology, SUNY Upstate Medical University, Syracuse, NY 13210
Department of Chemistry, Auburn University, Auburn, AL 36849
** Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221
Department of Biological Sciences, University of Cincinnati, Cincinnati, OH 45221
1 To whom correspondence should be addressed. e-mail: edna.kaneshiro{at}uc.edu
Pneumocystis causes a type of pneumonia in immunodeficient mammals, such as AIDS patients. Mammals cannot alkylate the C-24 position of the sterol side chain, nor can they desaturate C-22. Thus, the reactions leading to these sterol modifications are particularly attractive targets for the development of drugs against fungal and protozoan pathogens that make them. In the present study, the definitive structures of 43 sterol molecular species in rat-derived Pneumocystis carinii were elucidated by nuclear magnetic resonance spectroscopy. Ergosterol,
5,7 sterols, trienes, and tetraenes were not among them. Most (32 of the 43) were 24-alkylsterols, products of S-adenosyl-L-methionine:C-24 sterol methyl transferase (SAM:SMT) enzyme activity. Their abundance is consistent with the suggestion that SAM:SMT is highly active in this organism and that the enzyme is an excellent anti-Pneumocystis drug target. In contrast, the comprehensive analysis strongly suggest that P. carinii does not form
22 sterols, thus C-22 desaturation does not appear to be a drug target in this pathogen.
The lanosterol derivatives, 24-methylenelanost-8-en-3ß-ol and (Z)-24-ethylidenelanost-8-en-3ß-ol (pneumocysterol), previously identified in human-derived Pneumocystis jiroveci, were also detected among the sterols of the rat-derived P. carinii organisms.
Abbreviations: GLC, gas-liquid chromatography; MS, mass spectrometry; PcP, Pneumocystis pneumonia; RRT, relative retention time; SAM:SMT, S-adenosyl-L-methionine:C-24 sterol methyl transferase
Supplementary key words AIDS 24-alkylsterols drug targets gas-liquid chromatography mass spectrometry opportunistic infections nuclear magnetic resonance spectroscopy pneumocysterol S-adenosyl-L-methionine:C-24 sterol methyl transferase
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Journal of Biological Chemistry |
| Molecular and Cellular Proteomics | ASBMB Today |