B. fragilis- a anaerobe E Fairly long-term survival in aerated environment E Quick recovery of growth when oxygen is nearly exhausted EY B f outgrows common facultative anaerobes like E. coli under anaerobic conditions 2 How might these properties affect colonization and pathogenesis?
B. fragilis - a nanaerobe 16 Fairly long-term survival in aerated environment Quick recovery of growth when oxygen is nearly exhausted B. f. outgrows common facultative anaerobes like E. coli under anaerobic conditions How might these properties affect colonization and pathogenesis?
B. fragilis特殊生物学性状 Aerotolerance耐氧 Sphingolipid synthesis鞘脂合成 Low endotoxity LPS低内毒素活性脂多糖 Zwitterionic polysacchride capsule两性离子多糖 荚膜 ·BFT外毒素 · Antibiotic resistance抗生素抗性
B. fragilis 特殊生物学性状 17 • Aerotolerance 耐氧 • Spingolipid synthesis 鞘脂合成 • Low endotoxity LPS 低内毒素活性脂多糖 • Zwitterionic polysacchride capsule 两性离子多糖 荚膜 • BFT 外毒素 • Antibiotic resistance 抗生素抗性
Sphingolipid鞘脂 Sphingosine 真核生物生物膜 CHAo+ 重要组分及信号分 子 Ceramide 细菌中仅有的鞘 Fatty acid 脂合成菌: Substituent(R) Sphingolipid H Ceramide √拟杆菌门 Phosphocholine Sphingomyelin Sugar(s) Glycosphingolipid (GSL) √变形菌门α-变形菌纲 General sphingolipid structure Sphingomonadales目 (其中 Sphingomonas属 Expert Reviews in Molecular Medicine @2002 Cambridge University Press 无LPS,以糖鞘脂代之)
Sphingolipid 鞘脂 18 • 真核生物生物膜 重要组分及信号分 子 • 细菌中仅有的鞘 脂合成菌： 拟杆菌门 变形菌门-变形菌纲 Sphingomonadales目 (其中Sphingomonas属 无LPS，以糖鞘脂代之) (GSL)
Bacterial glycolipids require APC processing INKT cell TCR 5. 3 microbe microbial lipids dendritic CD1d cell http://faculty.ccbcmd.edu/courses/bio141/lecguide/unit6/intro/inktcell/microbiallipidsDcinKtcEll.html19
Bacterial glycolipids require APC processing 19 http://faculty.ccbcmd.edu/courses/bio141/lecguide/unit6/intro/iNKTcell/microbial_lipids_DC_iNKTcell.html
Glycolipid antigens are presented to iNKT NK11(cD161) semi-invariant TCR CD1d IFN-Y, TNF-a 4,-13←iNKT APC chemokines erforin FasL glycolipid CD4 Ly49 OH (CH2)23CH3 KRN7000 (a-GalCer) HO NH OH HO (CH2)12CR OH Van Kaer, L, et al.(2011). Cell Tissue Res 343(1):43-55
Glycolipid antigens are presented to iNKT 20 Van Kaer, L., et al. (2011). Cell Tissue Res 343(1): 43-55