11,119 results match your criteria pilus

Atomic and Electronic Structure of Pilus from through QM/MM Calculations: Evidence for Hole Transfer in Aromatic Residues.

J Phys Chem B 2021 Jul 22. Epub 2021 Jul 22.

Institute of Chemistry, Department of Engineering, Physics and Mathematics, São Paulo State University, Prof. Francisco Degni 55, 14800-060 Araraquara, Brazil.

Long-range electron transport has been widely and experimentally reported in pilus protein. However, a better understanding of the still undefined molecular arrangement can bring to light the role of key residues in this phenomenon. We propose a theoretical investigation of the electronic structure of aromatic residue groups in the protein through a classical molecular dynamics (MD) simulation, followed by a quantum mechanics/molecular mechanics (QM/MM) electronic study of different frames sampled from MD trajectories, an electrostatic potential and electron density analysis, an analysis of the density of states, and an investigation of hole formation through Dyson orbital calculations. Read More

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Evolution of a σ-(c-di-GMP)-anti-σ switch.

Proc Natl Acad Sci U S A 2021 Jul;118(30)

Department of Molecular Microbiology, John Innes Centre, Norwich NR4 7UH, United Kingdom;

Filamentous actinobacteria of the genus have a complex lifecycle involving the differentiation of reproductive aerial hyphae into spores. We recently showed c-di-GMP controls this transition by arming a unique anti-σ, RsiG, to bind the sporulation-specific σ, WhiG. The RsiG-(c-di-GMP)-WhiG structure revealed that a monomeric RsiG binds c-di-GMP via two E(X)S(X)R(X)Q(X)D repeat motifs, one on each helix of an antiparallel coiled-coil. Read More

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Interplay between meropenem and human serum albumin on expression of carbapenem resistance genes and natural competence in .

Antimicrob Agents Chemother 2021 Jul 19:AAC0101921. Epub 2021 Jul 19.

Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, California, USA.

A118, a mostly susceptible strain and AB5075, carbapenem-resistant, were cultured in Lysogeny broth (LB) or LB with different supplements: 3.5% human serum albumin (HSA), human serum (HS), meropenem, or meropenem plus 3.5% HSA. Read More

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Clp is a "busy" transcription factor in the bacterial warrior, .

Comput Struct Biotechnol J 2021 16;19:3564-3572. Epub 2021 Jun 16.

College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, PR China.

Cyclic AMP receptor protein (CRP) is a well-characterized group of global transcription factors in bacteria. They are known to regulate numerous cellular processes by binding DNA and/or cAMP (a ligand called bacterial second messenger) to control target gene expression. Gram-negative is a soilborne, plant-beneficial bacterium without flagella that can fight against filamentous fungi and oomycete. Read More

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The LysR-Type Transcriptional Regulator BsrA (PA2121) Controls Vital Metabolic Pathways in .

mSystems 2021 Jul 13:e0001521. Epub 2021 Jul 13.

Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.

Pseudomonas aeruginosa, a facultative human pathogen causing nosocomial infections, has complex regulatory systems involving many transcriptional regulators. LTTR (LysR-Type Transcriptional Regulator) family proteins are involved in the regulation of various processes, including stress responses, motility, virulence, and amino acid metabolism. The aim of this study was to characterize the LysR-type protein BsrA (PA2121), previously described as a negative regulator of biofilm formation in P. Read More

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Crystal structure of the atypically adhesive SpaB basal pilus subunit: Mechanistic insights about its incorporation in lactobacillar SpaCBA pili.

Curr Res Struct Biol 2020 8;2:229-238. Epub 2020 Dec 8.

Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, 121001, India.

To successfully colonize a host or environment, certain genera and species of Gram-positive bacteria have evolved to utilize the so-called sortase-dependent pilus, a long multi-subunit and non-flagellar surface adhesin. One example of this is GG, a gut-adapted probiotic strain that produces SpaCBA pili. These structures are covalent hetero-oligomers built from three types of pilin subunit, each with a specific location and function (i. Read More

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December 2020

SdiA, a Quorum-Sensing Regulator, Suppresses Fimbriae Expression, Biofilm Formation, and Quorum-Sensing Signaling Molecules Production in .

Front Microbiol 2021 21;12:597735. Epub 2021 Jun 21.

Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil.

is a Gram-negative pathogen that has become a worldwide concern due to the emergence of multidrug-resistant isolates responsible for various invasive infectious diseases. Biofilm formation constitutes a major virulence factor for and relies on the expression of fimbrial adhesins and aggregation of bacterial cells on biotic or abiotic surfaces in a coordinated manner. During biofilm aggregation, bacterial cells communicate with each other through inter- or intra-species interactions mediated by signallng molecules, called autoinducers, in a mechanism known as quorum sensing (QS). Read More

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Type VI secretion system killing by commensal is influenced by expression of type four pili.

Elife 2021 07 7;10. Epub 2021 Jul 7.

Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.

Type VI Secretion Systems (T6SSs) are widespread in bacteria and can dictate the development and organisation of polymicrobial ecosystems by mediating contact dependent killing. In species, including a commensal of the human respiratory tract, interbacterial contacts are mediated by Type four pili (Tfp) which promote formation of aggregates and govern the spatial dynamics of growing microcolonies. Here, we show that expresses a plasmid-encoded T6SS that is active and can limit growth of related pathogens. Read More

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Effects of flavophospholipol on conjugation and plasmid curing of multidrug-resistant Enteritidis in broiler chickens.

JAC Antimicrob Resist 2021 Mar 11;3(1):dlab022. Epub 2021 Mar 11.

Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, A100R Sisson Hall, 1920 Coffey Rd, Columbus, OH 43210, USA.

Background: Early studies suggested that flavophospholipol has plasmid-curing effects and could inhibit conjugation by disrupting pilus formation between bacteria.

Objectives: This 36-day controlled-challenge study aimed to evaluate the anti-conjugative and plasmid-curing effect of flavophospholipol on plasmid-mediated antimicrobial resistance (AMR) in MDR transconjugant Enteritidis in chickens.

Methods: A total of 270-day-old chicks were randomly assigned to four control and four treatment groups with two doses of in-feed flavophospholipol (10 ppm and 64 ppm) and in the presence and absence of ampicillin in drinking water. Read More

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Crash landing of by MSHA pili-assisted braking and anchoring in a viscoelastic environment.

Elife 2021 Jul 2;10. Epub 2021 Jul 2.

Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.

Mannose-sensitive hemagglutinin (MSHA) pili and flagellum are critical for the surface attachment of , the first step of colonization on host surfaces. However, the cell landing mechanism remains largely unknown, particularly in viscoelastic environments such as the mucus layers of intestines. Here, combining the cysteine-substitution-based labeling method with single-cell tracking techniques, we quantitatively characterized the landing of by directly observing both pili and flagellum of cells in a viscoelastic non-Newtonian solution consisting of 2% Luria-Bertani and 1% methylcellulose (LB+MC). Read More

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The Two-Component System 09 of Is Important for Metabolic Fitness and Resistance during Dissemination in the Host.

Microorganisms 2021 Jun 23;9(7). Epub 2021 Jun 23.

Center for Functional Genomics of Microbes, Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, 17487 Greifswald, Germany.

The two-component regulatory system 09 of has been shown to modulate resistance against oxidative stress as well as capsule expression. These data and the implication of TCS09 in cell wall integrity have been shown for serotype 2 strain D39. Other data have suggested strain-specific regulatory effects of TCS09. Read More

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Clonal distribution, antimicrobial resistance, and pilus islets in S.pneumoniae isolates recovered from PCV10-vaccinated children with suppurative AOM in Bulgaria (2015-2020), BULGARIA.

Jpn J Infect Dis 2021 Jun 30. Epub 2021 Jun 30.

Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, Bulgaria.

Streptococcus pneumoniae is still a leading bacterial pathogen of acute otitis media (AOM), despite the available pneumococcal conjugate vaccines (PCVs). We conducted a study on the population structure, antibiotic nonsusceptibility, serotype distribution, and presence of pilus in middle ear fluids - S. pneumoniae isolates recovered from PCV10-vaccinated children with suppurative АОМ in Bulgaria. Read More

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Evidence of Common Isolates of in Bovines and Humans in Emilia Romagna Region (Northern Italy).

Front Microbiol 2021 11;12:673126. Epub 2021 Jun 11.

Experimental Zooprophylactic Institute in Lombardy and Emilia Romagna, Brescia, Italy.

(group B , GBS) is one of the most important agents of bovine mastitis and causes remarkable direct and indirect economic losses to the livestock sector. Moreover, this species can cause severe human diseases in susceptible individuals. To investigate the zoonotic potential of , 203 sympatric isolates from both humans and cattle, isolated in the same time frame (2018) and in the same geographic area (Emilia Romagna region, Northern Italy), were characterized by molecular capsular typing (MCT), pilus island typing (PI), and multi-locus sequence typing (MLST). Read More

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Unusual finding of the human-adapted hypervirulent serotype III/ST17 clone in a historical bovine Group B Streptococcus isolate from Brazil.

Braz J Microbiol 2021 Jun 23. Epub 2021 Jun 23.

Instituto de Microbiologia Paulo de Goes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil.

Group B Streptococcus (GBS) is a leading cause of human neonatal infections and bovine mastitis. We report here the unusual finding of the human-adapted hypervirulent serotype III/ST17 clone in a bovine GBS isolated in 1987 in Brazil. This isolate shared several phenotypic and genotypic characteristics with serotype III/ST17 strains obtained from human sources, including PFGE pattern, pilus genes, lactose fermentation, DNase activity, and antimicrobial susceptibility profile, highlighting the importance of continued tracking of GBS in the One Health scope. Read More

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Sef fimbria operon construction, expression, and function for direct rapid detection of Salmonella Enteritidis.

Appl Microbiol Biotechnol 2021 Jul 22;105(13):5631-5641. Epub 2021 Jun 22.

College of Veterinary Medicine, Yangzhou University, 12 East Wenhui Road, Yangzhou, 225009, China.

Salmonella Enteritidis (SE) causes both horizontal and vertical transmission of diseases in poultry industry and is also one of the main causes of human food poisoning. Sequence analysis of the sef operon of poultry-derived Salmonella serotypes showed the presence of an entire sef operon in SE, whereas only sef pseudogenes were found in Salmonella Gallinarum and Salmonella Pullorum. Subsequently, the sef operon of SE was cloned into the pBR322 plasmid and expressed in a modified Escherichia coli strain SE5000. Read More

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A novel PilR/PilS two-component system regulates NE pilus production in .

J Bacteriol 2021 Jun 21:JB0009621. Epub 2021 Jun 21.

Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, Ontario Canada N1G 5C9.

causes necrotic enteritis (NE) in poultry. A chromosomal locus (VR-10B) was previously identified in NE-causing strains that encodes an adhesive pilus (NE pilus), along with a two-component system (TCS), designated here as PilRS. While the NE pilus is important in pathogenesis, the role of PilRS remains to be determined. Read More

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Acinetobacter baylyi regulates type IV pilus synthesis by employing two extension motors and a motor protein inhibitor.

Nat Commun 2021 06 18;12(1):3744. Epub 2021 Jun 18.

Department of Biology, Indiana University, Bloomington, IN, USA.

Bacteria use extracellular appendages called type IV pili (T4P) for diverse behaviors including DNA uptake, surface sensing, virulence, protein secretion, and twitching motility. Dynamic extension and retraction of T4P is essential for their function, and T4P extension is thought to occur through the action of a single, highly conserved motor, PilB. Here, we develop Acinetobacter baylyi as a model to study T4P by employing a recently developed pilus labeling method. Read More

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Functional dissection of structural regions of the Thermus thermophilus competence protein PilW: Implication in secretin complex stability, natural transformation and pilus functions.

Biochim Biophys Acta Biomembr 2021 Jun 16;1863(10):183666. Epub 2021 Jun 16.

Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany. Electronic address:

Uptake of DNA from the environment into the bacterial cytoplasm is mediated by a macromolecular transport machinery that is similar in structure and function to type IV pili (T4P) and, indeed, DNA translocator and T4P share common components. One is the secretin PilQ which is assembled into homopolymeric complexes forming highly dynamic outer membrane (OM) channels mediating pilus extrusion and DNA uptake. How PilQ interacts with the motor is still enigmatic. Read More

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Provokes Exosome Secretion and Paracrine Immune Senescence in Bystander Dendritic Cells.

Front Cell Infect Microbiol 2021 1;11:669989. Epub 2021 Jun 1.

Department of Periodontics, Dental College of Georgia, Augusta University, Augusta, GA, United States.

Periodontitis is a disease of ageing or inflammaging, and is comorbid with other more severe age-related chronic diseases. With advanced age comes an increase in accumulation of senescent cells that release soluble and insoluble pro-inflammatory factors collectively termed the senescence associated secretory phenotype (SASP). In the present report, we examined whether immune cells typical of those at the oral mucosa-microbe interface, are vulnerable to cellular senescence (CS) and the role of dysbiotic oral pathogen . Read More

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Characterization of a bacterial strain Lactobacillus paracasei LP10266 recovered from an endocarditis patient in Shandong, China.

BMC Microbiol 2021 Jun 17;21(1):183. Epub 2021 Jun 17.

Department of Clinical Laboratory, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, 250021, Shandong, China.

Background: Lactobacilli are often recognized as beneficial partners in human microbial environments. However, lactobacilli also cause diseases in human, e.g. Read More

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The oligosaccharyltransferase AglB supports surface-associated growth and iron oxidation in .

Appl Environ Microbiol 2021 Jun 16:AEM0099521. Epub 2021 Jun 16.

Department of Plant and Microbial Biology, University of Minnesota, Twin Cities, St. Paul, MN, 55108.

Most microbial organisms grow as surface-attached communities known as biofilms. However, the mechanisms whereby methanogenic archaea grow attached to surfaces have remained understudied. Here, we show that the oligosaccharyltransferase AglB is essential for growth of strain JJ on glass or metal surfaces. Read More

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Mechanisms of Transforming DNA Uptake to the Periplasm of Bacillus subtilis.

mBio 2021 06 15;12(3):e0106121. Epub 2021 Jun 15.

Public Health Research Institute, Rutgers University, Newark, New Jersey, USA.

We demonstrate here that the acquisition of DNase resistance by transforming DNA, often assumed to indicate transport to the cytoplasm, reflects uptake to the periplasm, requiring a reevaluation of conclusions about the roles of several proteins in transformation. The new evidence suggests that the transformation pilus is needed for DNA binding to the cell surface near the cell poles and for the initiation of uptake. The cellular distribution of the membrane-anchored ComEA of Bacillus subtilis does not dramatically change during DNA uptake as does the unanchored ComEA of and . Read More

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Lactate-induced dispersal of microcolonies is mediated by changes in cell density and pilus retraction and is influenced by temperature change.

Infect Immun 2021 Jun 14:IAI0029621. Epub 2021 Jun 14.

Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden.

is the etiologic agent of meningococcal meningitis and sepsis. Initial colonization of meningococci to the upper respiratory tract epithelium is crucial for disease development. The colonization occurs in several steps and expression of type IV pili (Tfp) is essential for both attachment and microcolony formation of encapsulated bacteria. Read More

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Minor pilins are involved in motility and natural competence in the cyanobacterium Synechocystis sp. PCC 6803.

Mol Microbiol 2021 Jun 11. Epub 2021 Jun 11.

Molecular Genetics, Institute of Biology III, University of Freiburg, Freiburg, Germany.

Cyanobacteria synthesize type IV pili, which are known to be essential for motility, adhesion and natural competence. They consist of long flexible fibers that are primarily composed of the major pilin PilA1 in Synechocystis sp. PCC 6803. Read More

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Phylogenomic Characterization of a Novel Species Associated with Fatal Diphtheritic Stomatitis in Endangered Yellow-Eyed Penguins.

mSystems 2021 Jun 8;6(3):e0032021. Epub 2021 Jun 8.

Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom.

Yellow-eyed penguins, Megadyptes antipodes, are an endangered species that are endemic to New Zealand. Outbreaks of diphtheritic stomatitis have caused significant mortality for this species, especially among young chicks. In this study, we isolated 16 sp. Read More

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Distinct Patterns of Host Adherence by Isolated from Experimental Gonorrhea.

Can J Infect Dis Med Microbiol 2021 13;2021:7865405. Epub 2021 May 13.

Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, China.

( gonococci, or GC), the etiologic agent of gonorrhea, is a human-obligate bacterial pathogen. The GC surface contains pili that mediate the adherence to host cells. Studies have shown that GC pili, coded by pilin genes, undergo remarkable changes during human experimental gonorrhea, possibly generated by DNA phase variation during infection. Read More

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Genomic Characterization of the Novel sp. Isolated from the Blood of a (Pallas, 1811).

Vector Borne Zoonotic Dis 2021 Jun 16;21(6):432-440. Epub 2020 Jun 16.

UMR VITROME, Aix-Marseille University, Institut pour la Recherche et le Développement, Service de Santé des Armées, Assistance Publique-Hôpitaux de Marseille, Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France.

species are reemerging infectious agents that are transmitted by arthropod vectors among animals and/or humans. At least 13 of the 35 currently recognized species are pathogenic for humans. Most of the pathogenic species, except and are zoonotic agents with animal reservoirs, including cats, dogs, coyotes, foxes, cattle, and rodents. Read More

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Expression of Antigens Fused to Different Vectors and Their Effectiveness as Vaccines.

Vaccines (Basel) 2021 May 21;9(6). Epub 2021 May 21.

State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing 100071, China.

Pertussis is an acute respiratory tract infection caused by . Even though its current vaccine coverage is relatively broad, they still have some shortcomings such as short protection time and might be incapable of blocking the spread of the disease. In this study, we developed new pertussis vaccine candidates by separately fusing three pertussis antigens ( fimbriae 2 "Fim2", pertussis toxin S1 subunit "PtxS1", and filamentous hemagglutinin "FHA") to each of two immune-boosting carrier proteins (B subunits of AB5 toxin family: cholera toxin B subunit "CTB" and shiga toxin B subunit "StxB"). Read More

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Influence of seasonal changes and salinity on spinach phyllosphere bacterial functional assemblage.

PLoS One 2021 1;16(6):e0252242. Epub 2021 Jun 1.

US Salinity Laboratory, USDA-ARS, Riverside, CA, United States of America.

The phyllosphere is the aerial part of plants that is exposed to different environmental conditions and is also known to harbor a wide variety of bacteria including both plant and human pathogens. However, studies on phyllosphere bacterial communities have focused on bacterial composition at different stages of plant growth without correlating their functional capabilities to bacterial communities. In this study, we examined the seasonal effects and temporal variabilities driving bacterial community composition and function in spinach phyllosphere due to increasing salinity and season and estimated the functional capacity of bacterial community16S V4 rRNA gene profiles by indirectly inferring the abundance of functional genes based on metagenomics inference tool Piphillin. Read More

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Circulation of Extended-Spectrum Beta-Lactamase-Producing of Pandemic Sequence Types 131, 648, and 410 Among Hospitalized Patients, Caregivers, and the Community in Rwanda.

Front Microbiol 2021 14;12:662575. Epub 2021 May 14.

Pharmaceutical Microbiology, Institute of Pharmacy, University of Greifswald, Greifswald, Germany.

Multi-drug resistant (MDR), gram-negative , such as () limit therapeutic options and increase morbidity, mortality, and treatment costs worldwide. They pose a serious burden on healthcare systems, especially in developing countries like Rwanda. Several studies have shown the effects caused by the global spread of extended-spectrum beta-lactamase (ESBL)-producing . Read More

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