Translocation of the Helicobacter pylori (Hp) cytotoxin-associated gene A (CagA) effector protein via cag-Type IV Secretion System (T4SS) into host cells is a major risk factor for severe gastric diseases, including cancer. However, mechanism translocation and requirements from cell that event are not well understood. The T4SS consists inner- outer membrane-spanning Cag complexes surface-located pilus. Previously an arginine-glycine-aspartate (RGD)-dependent typical integrin/ligand type...

Summary Fur, the ferric uptake regulator, is a transcription factor that controls iron metabolism in bacteria. Binding of ferrous to Fur triggers conformational change activates protein for binding specific DNA sequences named boxes. In Helicobacter pylori , HpFur involved acid response and important gastric colonization model animals. Here we present crystal structure functionally active mutant (HpFur2M; C78S‐C150S) bound zinc. Although its fold similar other Fur‐like proteins, reveals...

Crystal clear: Preparing solid-state NMR samples that yield high-resolution spectra displaying high sensitivity is time-consuming and complicated. A sample of the 59 kDa protein DnaB, prepared simply by preparative centrifugation, provides are as good ones from carefully grown microcrystals. Detailed facts importance to specialist readers published "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They made available submitted authors. Please note: The...

Infection with the gastric pathogen Helicobacter pylori is a risk factor for development of cancer. Pathogenic strains H. carry type IV secretion system (T4SS) responsible injection oncoprotein CagA into host cells. and its cag-T4SS exploit α5β1 integrin as receptor translocation. Injected localizes to inner leaflet cell membrane, where it hijacks signaling induces cytoskeleton reorganization. Here we describe crystal structure N-terminal ~100-kDa subdomain at 3.6 Å that unveils unique...

Type IV secretion systems (T4SSs) are commonly used machineries in Gram-negative bacteria. They the infection of human, animal, or plant cells and propagation antibiotic resistance. The T4SS apparatus spans both membranes bacterium generally is composed 12 proteins, named VirB1–11 VirD4 after proteins canonical Agrobacterium tumefaciens T4SS. periplasmic core complex VirB8/VirB10 structurally functionally links cytoplasmic NTPases system with its outer membrane pilus components. Here we...

Abstract Acetaldehyde–alcohol dehydrogenase (AdhE) enzymes are a key metabolic enzyme in bacterial physiology and pathogenicity. They convert acetyl-CoA to ethanol via an acetaldehyde intermediate during fermentation anaerobic environment. This two-step reaction is associated NAD + regeneration, essential for glycolysis. The bifunctional AdhE conserved all kingdoms but also more phylogenetically distant microorganisms such as green microalgae. It found oligomeric form called spirosomes,...

Brucella species are facultative intracellular Gram-negative bacteria relevant to animal and human health. Their ability establish an niche subvert host cell pathways their advantage depends on the delivery of bacterial effector proteins through a type IV secretion system. Toll/Interleukin-1 Receptor (TIR)-domain-containing BtpA (also known as TcpB) BtpB among such effectors. Although divergent in primary sequence, they interfere with Toll-like receptor (TLR) signaling inhibit innate immune...

Abstract Paramagnetic metal ions deliver structural information both in EPR and solid‐state NMR experiments, offering a profitable synergetic approach to study bio‐macromolecules. We demonstrate the spectral consequences of Mg 2+ / Mn substitution resulting contents for two different ATP:Mg ‐fueled protein engines, DnaB helicase from Helicobacter pylori active bacterial replisome, ABC transporter BmrA, efflux pump. show that, while spectra report on binding provide geometry centers proteins,...

Translocation of the Helicobacter pylori (Hp) cytotoxin-associated gene A (CagA) effector protein via cag-Type IV Secretion System (cag-T4SS) into host cells is a hallmark infection with Hp and major risk factor for severe gastric diseases, including cancer. To mediate injection CagA, uses membrane-embedded syringe-like molecular apparatus extended by an external pilus-like rod structure that binds cell surface integrin heterodimers. It still largely unclear how interaction cag-T4SS finally...

5-Nitroimidazole-based antibiotics are compounds extensively used for treating infections in humans and animals caused by several important pathogens. They administered as prodrugs, their activation depends upon an anaerobic 1-electron reduction of the nitro group a pathway cells. Bacterial resistance toward these drugs is thought to be decreased drug uptake and/or altered efficiency. One class resistant strains, identified Bacteroides, has been shown carry Nim genes (NimA, -B, -C, -D, -E),...

The virulence of Francisella tularensis, the etiological agent tularemia, relies on an atypical type VI secretion system (T6SS) encoded by a genomic island termed Pathogenicity Island (FPI). While importance FPI in F. tularensis is clearly established, precise role most FPI-encoded proteins remains to be deciphered. In this study, using highly virulent strains and closely related species novicida, IglG was characterized as protein featuring unique α-helical N-terminal extension domain...

Abstract DnaB helicases are motor proteins that couple ATP-hydrolysis to the loading of protein onto DNA at replication fork and translocation along separate double-stranded into single strands during replication. Using a network conformational states, arrested by nucleotide mimics, we herein characterize reaction coordinates for ATP hydrolysis, using solid-state NMR spectroscopy. AMP-PCP is used as pre-hydrolytic, ADP:AlF 4 − transition state, ADP post-hydrolytic mimic. 31 P 13 C spectra...

Replicative helicases are essential ATPases that unwind DNA to initiate chromosomal replication. While bacterial replicative DnaB hexameric, Helicobacter pylori (HpDnaB) was found form double hexamers, similar some archaeal and eukaryotic helicases. Here we present a structural functional analysis of HpDnaB protein during primosome formation. The crystal structure the at 6.7 Å resolution reveals dodecameric organization consisting two hexamers assembled via their N-terminal rings in...

Bacterial DNA replication requires DnaA, an AAA+ ATPase that initiates at a specific chromosome region, oriC, and is regulated by species-specific regulators directly bind DnaA. HobA DnaA binding protein, recently identified as essential regulator of in Helicobacter pylori. We report the crystal structure complex with domains I II (DnaA(I-II)) from H. pylori, first bound to one its regulators. Biochemical characterization formed shows tetramer binds four DnaA(I-II) molecules, unable...

BtpA/Btp1/TcpB is a virulence factor produced by Brucella species that possesses Toll interleukin‐1 receptor (TIR) domain. Once delivered into the host cell, BtpA interacts with MyD88 to interfere TLR signalling and modulates microtubule dynamics. Here crystal structure of TIR domain at 3.15 Å presented. The shows dimeric arrangement canonical domain, similar Paracoccus denitrificans Tir protein but secured unique long N‐terminal α‐tail packs against TIR:TIR dimer. Structure‐based mutations...

The TIR domain-containing proteins BtpA/Btp1/TcpB and BtpB are translocated into host cells by the facultative intracellular bacterial pathogen Brucella. Here, they interfere with Toll like receptor signalling to temper inflammatory response. BtpA has also been found modulate microtubule dynamics. In both we identified a WxxxE motif, previously shown be an essential structural component in family of type III secretion system effectors that actin dynamics functioning as guanine nucleotide...

Abstract Bacterial pathogens often subvert the innate immune system to establish a successful infection. The direct inhibition of downstream components pathways is particularly well documented but how bacteria interfere with receptor proximal events far less understood. Here, we describe Toll/interleukin 1 ( TIR ) domain‐containing protein (PumA) multi‐drug resistant Pseudomonas aeruginosa PA 7 strain. We found that PumA essential for virulence and inhibits NF ‐κB, property transferable...

Abstract The cell nucleus is a primary target for intracellular bacterial pathogens to counteract immune responses and hijack host signalling pathways cause disease. Here we identify two Brucella abortus effectors, NyxA NyxB, that interfere with protease SENP3, this facilitates replication of the pathogen. translocated Nyx effectors directly interact SENP3 via defined acidic patch (identified from crystal structure NyxB), preventing nucleolar localisation at late stages infection. By...

NikR is a transcriptional metalloregulator central in the mandatory response to acidity of Helicobacter pylori that controls expression numerous genes by binding specific promoter regions. NikR/DNA interactions were proposed rely on protein activation Ni(II) high-affinity (HA) and possibly secondary external (X) sites. We describe biochemical characterization HpNikR mutants shows HA sites are essential but not sufficient for DNA binding, while residues from dimer–dimer interface important...

We have investigated a large set of interactions from the Helicobacter pylori protein interaction map previously identified by high-throughput yeast two-hybrid (htY2H)-based methods. This study had two aims: i) to validate htY2H as source protein-protein complexes for biochemical and structural studies H. interactome; ii) biochemically shown involve components type IV secretion systems. Thus, 17 involving 31 proteins fragments were studied, general strategy was designed produce...

Highly pathogenic strains of Helicobacter pylori use a type IV secretion system to inject the CagA protein into human gastric cells. There, associates with inner side membrane and is tyrosine-phosphorylated at EPIYA motifs by host kinases. The phosphorylation triggers series interactions between proteins that result in dramatic change cellular morphology. Structural functional analyses have proved difficult, due proteolytically sensitive nature recombinant protein. To circumvent these...