title: Helicobacter pylori cholesteryl glucosides interfere with host membrane phase and affect type IV secretion system function during infection in AGS cells.
abstract: Helicobacter pylori infection is an aetiological cause of gastric disorders worldwide. H. pylori has been shown to assimilate and convert host cholesterol into cholesteryl glucosides (CGs) by cholesterol-α-glucosyltransferase encoded by capJ. Here, we show that CapJ-deficient (ΔcapJ) H. pylori resulted in greatly reduced type IV secretion system (TFSS)-associated activities, including the hummingbird phenotype of AGS cells, IL-8 production, CagA translocation/phosphorylation and CagA-mediated signalling events. Complementation of the ΔcapJ mutation with wild type cagJ or by adding CGs-containing lysates or exogenous fluorophore-tagged CGs reversed the mutant phenotypes. We also show that the wild-type but not ΔcapJ H. pylori recruited raft-associated components to sites of bacterial attachment. Fluorescence recovery after photobleaching (FRAP) analysis of AGS cells treated with fluorescence-tagged cholesterol/CGs revealed that there was a higher proportion of CGs associated with immobile fractions. CGs-associated membranes were also more resistant to a cold detergent extraction. Thus, we propose that CGs synthesized by H. pylori around host-pathogen contact sites partition in detergent-resistant membranes (DRMs), alters lateral-phase segregation in membrane and reorganizes membrane architecture. These processes together promote the formation of a functional TFSS and H. pylori infection.
authors: Institute of Molecular and Cellular Biology and Department of Life Sciences, National Tsing-Hua University, Hsinchu, 30013, Taiwan.
authors: Hung-Jung
authors: HJ
authors: Wang
authors: Wen-Chi
authors: WC
authors: Cheng
authors: Hsin-Hung
authors: HH
authors: Cheng
authors: Chih-Ho
authors: CH
authors: Lai
authors: Wen-Ching
authors: WC
authors: Wang
mesh_terms: D000942:Antigens, Bacterial / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D058947:Bacterial Secretion Systems; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000382:microbiology*; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000378:metabolism; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics / Q000378:metabolism*; D006801:Humans
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems; C080866:cagA protein, Helicobacter pylori; C027578:cholesteryl glucoside; D002784:Cholesterol