Dataset Information

Human brain endothelial ATP synthase beta-subunit is mannose-insensitive binding target of FimH.

ABSTRACT: Binding of meningitis-causing Escherichia coli K1 to human brain microvascular endothelial cells (HBMEC) contributes to traversal of the blood-brain barrier, which occurs in part by the mannose-sensitive binding of FimH. In this study, we showed that FimH also binds to HBMEC, independent of mannose, and identified ATP synthase beta-subunit and actin proteins from the surface biotinylated HBMEC as the mannose-insensitive binding targets for FimH. Co-immunoprecipitation experiments in the presence of alpha-methyl mannose verified the binding of FimH to ATP synthase beta-subunit of HBMEC. ATP synthase beta-subunit antibody decreased E. coli K1 binding to HBMEC in the presence of alpha-methyl mannose. Taken together, these findings demonstrate that FimH of E. coli K1 binds to HBMEC in both mannose-sensitive and -insensitive manner.

SUBMITTER: Shin S

PROVIDER: S-EPMC2864485 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Human brain endothelial ATP synthase beta-subunit is mannose-insensitive binding target of FimH.

Shin Sooan S Kim Kwang Sik KS

FEMS microbiology letters 20091207 2

Binding of meningitis-causing Escherichia coli K1 to human brain microvascular endothelial cells (HBMEC) contributes to traversal of the blood-brain barrier, which occurs in part by the mannose-sensitive binding of FimH. In this study, we showed that FimH also binds to HBMEC, independent of mannose, and identified ATP synthase beta-subunit and actin proteins from the surface biotinylated HBMEC as the mannose-insensitive binding targets for FimH. Co-immunoprecipitation experiments in the presence ...[more]

PMID: 20067530

Similar Datasets

Project description:New findingsWhat is the central question of this study? Humans with obesity have lower ATP synthesis in muscle along with lower content of the β-subunit of the ATP synthase (β-F1-ATPase), the catalytic component of the ATP synthase. Does lower synthesis rate of β-F1-ATPase in muscle contribute to these responses in humans with obesity? What is the main finding and its importance? Humans with obesity have a lower synthesis rate of β-F1 -ATPase and ATP synthase specific activity in muscle. These findings indicate that reduced production of subunits forming the ATP synthase in muscle may contribute to impaired generation of ATP in obesity.AbstractThe content of the β-subunit of the ATP synthase (β-F1 -ATPase), which forms the catalytic site of the enzyme ATP synthase, is reduced in muscle of obese humans, along with a reduced capacity for ATP synthesis. We studied 18 young (37 ± 8 years) subjects of which nine were lean (BMI = 23 ± 2 kg m-2 ) and nine were obese (BMI = 34 ± 3 kg m-2 ) to determine the fractional synthesis rate (FSR) and gene expression of β-F1 -ATPase, as well as the specific activity of the ATP synthase. FSR of β-F1 -ATPase was determined using a combination of isotope tracer infusion and muscle biopsies. Gene expression of β-F1 -ATPase and specific activity of the ATP synthase were determined in the muscle biopsies. When compared to lean, obese subjects had lower muscle β-F1 -ATPase FSR (0.10 ± 0.05 vs. 0.06 ± 0.03% h-1 ; P < 0.05) and protein expression (P < 0.05), but not mRNA expression (P > 0.05). Across subjects, abundance of β-F1 -ATPase correlated with the FSR of β-F1 -ATPase (P < 0.05). The specific activity of muscle ATP synthase was lower in obese compared to lean subjects (0.035 ± 0.004 vs. 0.042 ± 0.007 arbitrary units; P < 0.05), but this difference was not significant after the activity of the ATP synthase was adjusted to the β-F1 -ATPase content (P > 0.05). Obesity impairs the synthesis of β-F1 -ATPase in muscle at the translational level, reducing the content of β-F1 -ATPase in parallel with reduced capacity for ATP generation via the ATP synthase complex.

Project description:PurposePrimary breast and prostate cancers can be cured, but metastatic disease cannot. Identifying cell factors that predict metastatic potential could guide both prognosis and treatment.MethodsWe used Cell-SELEX to screen an RNA aptamer library for differential binding to prostate cancer cell lines with high vs. low metastatic potential. Mass spectroscopy, immunoblot, and immunohistochemistry were used to identify and validate aptamer targets. Aptamer properties were tested in vitro, in xenograft models, and in clinical biopsies. Gene expression datasets were queried for target associations in cancer.ResultsWe identified a novel aptamer (Apt63) that binds to the beta subunit of F1Fo ATP synthase (ATP5B), present on the plasma membrane of certain normal and cancer cells. Apt63 bound to plasma membranes of multiple aggressive breast and prostate cell lines, but not to normal breast and prostate epithelial cells, and weakly or not at all to non-metastasizing cancer cells; binding led to rapid cell death. A single intravenous injection of Apt63 induced rapid, tumor cell-selective binding and cytotoxicity in MDA-MB-231 xenograft tumors, associated with endonuclease G nuclear translocation and DNA fragmentation. Apt63 was not toxic to non-transformed epithelial cells in vitro or adjacent normal tissue in vivo. In breast cancer tissue arrays, plasma membrane staining with Apt63 correlated with tumor stage (p < 0.0001, n = 416) and was independent of other cancer markers. Across multiple datasets, ATP5B expression was significantly increased relative to normal tissue, and negatively correlated with metastasis-free (p = 0.0063, 0.00039, respectively) and overall (p = 0.050, 0.0198) survival.ConclusionEcto-ATP5B binding by Apt63 may disrupt an essential survival mechanism in a subset of tumors with high metastatic potential, and defines a novel category of cancers with potential vulnerability to ATP5B-targeted therapy. Apt63 is a unique tool for elucidating the function of surface ATP synthase, and potentially for predicting and treating metastatic breast and prostate cancer.

Dataset Information

Human brain endothelial ATP synthase beta-subunit is mannose-insensitive binding target of FimH.

Publications

Human brain endothelial ATP synthase beta-subunit is mannose-insensitive binding target of FimH.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets