Anthrax toxin consists of three ∼ 85-kD proteins: lethal factor (LF), edema factor (EF), and protective antigen (PA). PA63 (the 63-kD, C-terminal portion of PA) forms heptameric channels ((PA63)7) in planar phospholipid bilayer membranes that enable the translocation of LF and EF across the membrane. These mushroom-shaped channels consist of a globular cap domain and a 14-stranded β-barrel stem domain, with six anionic residues lining the interior of the stem to form rings of negative charges. (PA63)7 channels are highly cation selective, and, here, we investigate the effects on both cation selectivity and protein translocation of mutating each of these anionic residues to a serine. We find that although some of these mutations reduce cation selectivity, selectivity alone does not directly predict the rate of protein translocation; local changes in electrostatic forces must be considered as well.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4516782PMC
http://dx.doi.org/10.1085/jgp.201511388DOI Listing

Publication Analysis

Top Keywords

protein translocation
12
anthrax toxin
8
anionic residues
8
cation selectivity
8
ion selectivity
4
selectivity anthrax
4
toxin channel
4
channel protein
4
translocation
4
translocation anthrax
4

Similar Publications

Introduction: Oxidative stress is an important cause of acetaminophen (APAP)-induced liver injury (AILI). Sakuranetin (Sak) is an antitoxin from the cherry flavonoid plant with good antioxidant effects. However, whether sakuranetine has a protective effect on APAP-induced liver injury is not clear.

View Article and Find Full Text PDF

Antiparasitic activity of the iron-containing milk protein lactoferrin and its potential derivatives against human intestinal and blood parasites.

Front Parasitol

February 2024

Department of Pharmacy Practice and Science, College of Pharmacy, University of Kentucky, Lexington, KY, United States.

An iron-containing milk protein named lactoferrin (Lf) has demonstrated antiparasitic and immunomodulatory properties against a variety of human parasites. This protein has shown its capability to bind and transport iron molecules in the vicinity of the host-pathogen environment. The ability of parasites to sequester the iron molecule and to increase their pathogenicity and survival depends on the availability of iron sources.

View Article and Find Full Text PDF

RPS23RG1 inhibits SORT1-mediated lysosomal degradation of MDGA2 to protect against autism.

Theranostics

January 2025

Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, China.

Mutations in the synaptic protein MAM domain containing glycosylphosphatidylinositol anchor 2 (MDGA2) have been associated with autism spectrum disorder (ASD). Therefore, elucidating the regulatory mechanisms of MDGA2 can help develop effective treatments for ASD. Liquid chromatography-tandem mass spectrometry was carried out to identify proteins interacting with the extracellular domain of RPS23RG1 and with MDGA2, followed by co-immunoprecipitation assays to confirm protein-protein interactions.

View Article and Find Full Text PDF

Unguarded liabilities: complex amino acid dependence exposes unique avenues of inhibition.

Front Antibiot

May 2024

Laboratory of Bacteriology, Rocky Mountain Laboratories, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States.

Recent reports from the Centers for Disease Control and Prevention approximate 500,000 cases of Lyme disease in the United States yearly, a significant economic burden on the healthcare system. The standard treatment for Lyme disease includes broad-spectrum antibiotics, which may be administered for extensive periods of time and result in significant impacts to the patient. Recently, we demonstrated that , the causative agent of Lyme disease, is uniquely dependent upon peptide acquisition via an oligopeptide transport (Opp) system.

View Article and Find Full Text PDF

Introduction: In response to continued public health emergency of antimicrobial resistance (AMR), a significant key strategy is the discovery of novel mycobacterial efflux-pump inhibitors (EPIs) as potential adjuvants in combination drug therapy. Interest in identifying new chemotypes which could potentially synergize with the existing antibiotics and can be deployed as part of a combination therapy. This strategy could delay the emergence of resistance to existing antibiotics and increase their efficacy against resistant strains of mycobacterial species.

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!