Chaperone-assisted cryo-EM structure of P. aeruginosa PhuR reveals molecular basis for heme uptake

Paweł P Knejski, Satchal K Erramilli, Anthony A Kossiakoff

bioRxiv. 2023 Aug 1:2023.08.01.551527.

PMID: 37577460 PMCID: PMC10418163 DOI: 10.1101/2023.08.01.551527

Pathogenic bacteria, such as Pseudomonas aeruginosa , depend on scavenging heme for the acquisition of iron, an essential nutrient. The TonB-dependent transporter (TBDT) PhuR is the major heme uptake protein in P. aeruginosa clinical isolates. However, a comprehensive understanding …

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Antiviral HIV-1 SERINC restriction factors disrupt virus membrane asymmetry

Susan A Leonhardt, Michael D Purdy, Jonathan R Grover, Ziwei Yang, Sandra Poulos, William E McIntire, Elizabeth A Tatham, Satchal K Erramilli, Kamil Nosol, Kin Kui Lai, Shilei Ding, Maolin Lu, Pradeep D Uchil, Andrés Finzi, Alan Rein, Anthony A Kossiakoff, Walther Mothes, Mark Yeager

Nature Communications volume 14, Article number: 4368 (2023)

PMID: 37474505 …

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ACKR3-arrestin2/3 complexes reveal molecular consequences of GRK-dependent barcoding

Qiuyan Chen, Christopher T Schafer, Somnath Mukherjee, Martin Gustavsson, Parth Agrawal, Xin-Qiu Yao, Anthony A Kossiakoff, Tracy M Handel, John J G Tesmer

bioRxiv 2023 Jul 19, 2023

PMID: 37502840 PMCID: PMC10370059 DOI: 10.1101/2023.07.18.549504

Atypical chemokine receptor 3 (ACKR3, also known as CXCR7) is a scavenger receptor that regulates extracellular levels of the chemokine CXCL12 …

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Cryo-EM structures of a synthetic antibody against 22 kDa claudin-4 reveal its complex with Clostridium perfringens enterotoxin

Satchal K Erramilli, Pawel K Dominik, Chinemerem P Ogbu, Anthony A Kossiakoff, Alex J Vecchio

bioRxiv 2023 Jun 12, 2023

PMID: 37398044 PMCID: PMC10312657 DOI: 10.1101/2023.06.12.544689

Claudins are a family of ∼25 kDa membrane proteins that integrate into tight junctions to form molecular barriers at the paracellular spaces between endothelial and epithelial cells. Humans have 27 subtypes, which homo- and hetero-oligomerize to …

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Conformation-specific Synthetic Antibodies Discriminate Multiple Functional States of the Ion Channel CorA

Satchal K. Erramilli, Pawel K. Dominik, Dawid Deneka , Piotr Tokarz , Sangwoo S. Kim, Bharat G. Reddy, Blazej M. Skrobek , Olivier Dalmas , Eduardo Perozo, Anthony A. Kossiakoff 

J Mol Biol. 2023

PMD: 37394032 PMID: 37394032 DOI: 10.1016/j.jmb.2023.168192

CorA, the primary magnesium ion channel in prokaryotes and archaea, is a prototypical homopentameric ion channel that undergoes ion-dependent conformational transitions. CorA adopts five-fold symmetric non-conductive states in the presence of high concentrations of Mg2+, and highly asymmetric …

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Characterization of synthetic antigen binding fragments targeting Toc75 for the isolation of TOC in A. thaliana and P. sativum

Karthik Srinivasan, Satchal K. Erramilli, Srinivas Chakravarthy, Adrian Gonzalez, Anthony Kossiakoff, Nicholas Noinaj

Structure. 2023 Mar 17; S0969-2126(23)00078-3.

PMID: 36977410 DOI: 10.1016/j.str.2023.03.002

Roughly 95% of the proteins that make up the chloroplast must be imported from the cytoplasm. The machinery responsible for the translocation of these cargo proteins is called the translocon at the outer …

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Structural basis for assembly and lipid-mediated gating of LRRC8A: C volume-regulated anion channels

David M Kern, Julia Bleier, Somnath Mukherjee, Jennifer M Hill, Anthony A Kossiakoff, Ehud Y Isacoff, Stephen G Brohawn

Nat Struct Mol Biol 2023 Mar 16

PMID: 36928458 DOI: 10.1038/s41594-023-00944-6

Leucine-rich repeat-containing protein 8 (LRRC8) family members form volume-regulated anion channels activated by hypoosmotic cell swelling. LRRC8 channels are ubiquitously expressed in vertebrate cells as …

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Isoform- and ligand-specific modulation of the adhesion GPCR ADGRL3/Latrophilin3 by a synthetic binder

Szymon P Kordon, Przemysław Dutka, Justyna M Adamska, Sumit J Bandekar, Katherine Leon, Satchal K Erramilli, Brock Adams, Jingxian Li, Anthony A Kossiakoff, Demet Araç

Nat Commun. 2023 Feb 6

PMID: 36746957 PMCID: PMC9902482 DOI: 10.1038/s41467-023-36312-7

Adhesion G protein-coupled receptors (aGPCRs) are cell-surface proteins with large extracellular regions that bind to multiple ligands to regulate …

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Structure, sequon recognition and mechanism of tryptophan C-mannosyltransferase

Joël S Bloch, Alan John, Runyu Mao, Somnath Mukherjee, Jérémy Boilevin, Rossitza N Irobalieva, Tamis Darbre, Nichollas E Scott, Jean-Louis Reymond, Anthony A Kossiakoff, Ethan D Goddard-Borger, Kaspar P Locher

Nat Chem Biol. 2023 Jan 5

PMID: 36604564 DOI: 10.1038/s41589-022-01219-9

C-linked glycosylation is essential for the trafficking, folding and function of secretory and transmembrane proteins …

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Development, structure, and mechanism of synthetic antibodies that target claudin and Clostridium perfringens enterotoxin complexes

Benjamin J. Orlando, Pawel K. Dominik, Sourav Roy, Chinemerem P. Ogbu, Satchal K. Erramilli, AnthonyA. Kossiakoff, Alex J. Vecchio

JBC Journal of Biological Chemistry 9 August 2022, 102357

PMID: 35952760 PMCID: PMC9463536 DOI: jbc.2022.102357

Strains of Clostridium perfringens produce a two-domain enterotoxin (CpE) that afflicts humans and domesticated animals, causing prevalent gastrointestinal illnesses. CpE’s C-terminal domain …

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