Identification of S-(2,3-Dihydroxypropyl)cystein in a Macrophage-Activating Lipopeptide from Mycoplasma fermentans
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- 作者：Peter F. Mü ; hlradt ; Holger Meyer ; and Rolf Jansen
- 刊名：Biochemistry
- 出版年：1996
- 出版时间：June 18, 1996
- 年：1996
- 卷：35
- 期：24
- 页码：7781 - 7786
- 全文大小：250K
- 年卷期：v.35,no.24(June 18, 1996)
- ISSN：1520-4995
文摘
Mycoplasmas are capable of stimulating monocytes and macrophagesto release cytokines,prostaglandins, and nitric oxide. The aim of this study was tocharacterize the chemical nature of thepreviously isolated [Mühlradt, P. F., & Frisch, M. (1994)Infect. Immun. 62, 3801-3807] macrophage-stimulating material "MDHM" from Mycoplasma fermentans.Mycoplasmas were delipidated, and MDHMactivity was extracted with octyl glucoside and further purified byreversed-phase HPLC. Macrophage-stimulating activity was monitored by nitric oxide release fromperitoneal macrophages from C3H/HeJendotoxin low responder mice. HPLC-purified MDHM wasrechromatographed on an analytic scale RP18 column before and after proteinase K treatment. Proteinasetreatment did not diminish biologicalactivity but shifted MDHM elution toward higher lipophilicity,suggesting that the macrophage-stimulatingactivity might reside in the lipopeptide moiety of a lipoprotein.Proteinase K-treated MDHM washydrolyzed, amino groups were dansylated, and the dansylated materialwas isolated by HPLC. DansylatedS-(2,3-dihydroxypropyl)cystein (glycerylcysteinthioether), typical for Braun's murein lipoprotein, andDns-Gly and Dns-Thr were identified by tandem mass spectrometry.These amino acids were isolatedfrom biologically active but not from the neighboring inactive HPLCfractions. IR spectra from proteinaseK-treated, HPLC-purified MDHM and those from the synthetic lipopeptide[2,3-bis(palmitoyloxy)-(2-RS)-propyl]-N-palmitoyl-(R)-CysSerSerAsnAlawere very similar. The data, taken together, indicatethatlipoproteins of a nature previously detected in eubacteria areexpressed in M. fermentans and that at leastone of these lipoproteins and a lipopeptide derived from it constitutethe macrophage-activating principleMDHM from these mycoplasmas.