Intermedilysin (ILY) is an unusual member of the family of cholesterol-dependent cytolysins because it binds to human CD59 (hCD59) rather than directly to cholesterol-rich membranes. Binding of ILY to hCD59 initiates a series of conformational changes within the toxin that result in the conversion of the soluble monomer into an oligomeric membrane-embedded pore complex. In this study the association of ILY with its membrane receptor has been examined throughout the assembly and formation of the pore complex. Using ILY mutants trapped at various stages of pore assembly, we show ILY remains engaged with hCD59 throughout the assembly of the prepore oligomer, but it disengages from the receptor upon the conversion to the pore complex. We further show that the assembly intermediates increase the sensitivity of the host cell to lysis by its complement membrane attack complex, apparently by blocking the hCD59-binding site for complement proteins C8alpha and C9.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2676001PMC
http://dx.doi.org/10.1074/jbc.M900772200DOI Listing

Publication Analysis

Top Keywords

pore complex
16
complex assembly
8
assembly intermediates
8
intermediates increase
8
host cell
8
assembly
6
pore
5
complex
5
ily
5
intermedilysin-receptor interactions
4

Similar Publications

Drug Development.

Alzheimers Dement

December 2024

Shoolini University, Solan, Himachal Pradesh, India.

Background: Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline, neuroinflammation, and mitochondrial dysfunction. In Alzheimer's, abnormal Mitochondrial Permeability Transition Pore (mPTP) activity may contribute to mitochondrial dysfunction and neuronal damage. Withanolide A, a naturally occurring compound derived from Withania somnifera, have shown potential neuroprotective effects in various neurological disorders.

View Article and Find Full Text PDF

Background: Sodium vanadium fluorophosphate is a sodium ion superconductor material with high sodium ion mobility and excellent cyclic stability, making it a promising cathode material for sodium-ion batteries. However, most of the literature and patents report preparation through traditional methods, which involve complex processes, large particle sizes, and low electronic conductivity, thereby limiting development progress.

Objective: Aiming at the limitation of high cost and poor performance of vanadium sodium fluorophosphate cathode material, the low temperature and high-efficiency nano preparation technology was developed.

View Article and Find Full Text PDF

Differentiated effects and mechanisms of N-, P-, S-, and Fe-modified biochar materials for remediating Cd- and Pb-contaminated calcareous soil.

Ecotoxicol Environ Saf

January 2025

MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China.

To investigate the remediation effects of various modified biochar materials derived from different impregnation agents on Cd- and Pb-contaminated calcareous soil, nitrogen (N-), phosphorus (P-), sulfur (S-), and iron (Fe-) modified biochar materials (NBC, PBC, SBC, FBC) were fabricated through the impregnation-pyrolysis method and employed to immobilize Pb and Cd in the calcareous soil. The characterization results showed that NBC exhibited an uneven pore size distribution and increased aromaticity, while PBC and SBC had increased pH and ash content. Pot experiments demonstrated significantly different effects of various modified biochar materials on soil immobilization and plant uptake of Cd and Pb.

View Article and Find Full Text PDF

Acute pancreatitis (AP) is an inflammatory disease of the pancreas and a complex process involving multiple factors, with mitochondrial damage playing a crucial role. Mitochondrial dysfunction is now considered a key driver in the development of AP. This dysfunction often presents as increased oxidative stress, altered membrane potential and permeability, and mitochondrial DNA damage and mutations.

View Article and Find Full Text PDF

Three-dimensional characterization of nanoporous membranes by capillary filling using high speed interferometry.

Rev Sci Instrum

January 2025

Dpto. de Física, Facultad de Ingeniería Química, Universidad Nacional del Litoral, S3000 Santa Fe, Argentina and Instituto de Física del Litoral, Santa Fe S3000, Argentina.

A high-speed interferometric system was developed to analyze nanostructured porous silicon (PS) membranes by measuring reflectance variations during capillary filling from both sides. A high-speed camera was employed to capture the reflectance evolution of the entire sample area with the necessary temporal resolution, providing quantitative information on filling dynamics. By integrating these data with a simple fluid dynamic model, it is possible to examine the internal structure of the membranes and determine the effective pore radii profiles along their thickness.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!