scholarly journals Revisiting Bap Multidomain Protein: More Than Sticking Bacteria Together

2020 ◽  
Vol 11 ◽  
Author(s):  
Jaione Valle ◽  
Xianyang Fang ◽  
Iñigo Lasa
Keyword(s):  
Biofilm Formation ◽  
Core Genome ◽  
Current Knowledge ◽  
Surface Proteins ◽  
Structure And Properties ◽  
Diverse Range ◽  
The Core ◽  
Self Assembling ◽  
Abiotic Surfaces ◽  
Range Of Functions

One of the major components of the staphylococcal biofilm is surface proteins that assemble as scaffold components of the biofilm matrix. Among the different surface proteins able to contribute to biofilm formation, this review is dedicated to the Biofilm Associated Protein (Bap). Bap is part of the accessory genome of Staphylococcus aureus but orthologs of Bap in other staphylococcal species belong to the core genome. When present, Bap promotes adhesion to abiotic surfaces and induces strong intercellular adhesion by self-assembling into amyloid like aggregates in response to the levels of calcium and the pH in the environment. During infection, Bap enhances the adhesion to epithelial cells where it binds directly to the host receptor Gp96 and inhibits the entry of the bacteria into the cells. To perform such diverse range of functions, Bap comprises several domains, and some of them include several motifs associated to distinct functions. Based on the knowledge accumulated with the Bap protein of S. aureus, this review aims to summarize the current knowledge of the structure and properties of each domain of Bap and their contribution to Bap functionality.

scholarly journals Functional Genomics of Enterococcus faecalis: Multiple Novel Genetic Determinants for Biofilm Formation in the Core Genome

2009 ◽  
Vol 191 (8) ◽  
pp. 2806-2814 ◽  
Author(s):  
Katie S. Ballering ◽  
Christopher J. Kristich ◽  
Suzanne M. Grindle ◽  
Ana Oromendia ◽  
David T. Beattie ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Biofilm Formation ◽  
Core Genome ◽  
Genetic Locus ◽  
Regulatory Protein ◽  
Genetic Determinants ◽  
Genetic Loci ◽  
Putative Promoter Region ◽  
Biofilm Growth ◽  
The Core

ABSTRACT The ability of Enterococcus faecalis to form robust biofilms on host tissues and on abiotic surfaces such as catheters likely plays a major role in the pathogenesis of opportunistic antibiotic-resistant E. faecalis infections and in the transfer of antibiotic resistance genes. We have carried out a comprehensive analysis of genetic determinants of biofilm formation in the core genome of E. faecalis. Here we describe 68 genetic loci predicted to be involved in biofilm formation that were identified by recombinase in vivo expression technology (RIVET); most of these genes have not been studied previously. Differential expression of a number of these determinants during biofilm growth was confirmed by quantitative reverse transcription-PCR, and genetic complementation studies verified a role in biofilm formation for several candidate genes. Of particular interest was genetic locus EF1809, predicted to encode a regulatory protein of the GntR family. We isolated 14 independent nonsibling clones containing the putative promoter region for this gene in the RIVET screen; EF1809 also showed the largest increase in expression during biofilm growth of any of the genes tested. Since an in-frame deletion of EF1809 resulted in a severe biofilm defect that could be complemented by the cloned wild-type gene, we have designated EF1809 ebrA (enterococcal biofilm regulator). Most of the novel genetic loci identified in our studies are highly conserved in gram-positive bacterial pathogens and may thus constitute a pool of uncharacterized genes involved in biofilm formation that may be useful targets for drug discovery.

scholarly journals Changes in the Expression of Biofilm-Associated Surface Proteins inStaphylococcus aureusFood-Environmental Isolates Subjected to Sublethal Concentrations of Disinfectants

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Lenka Cincarova ◽  
Ondrej Polansky ◽  
Vladimir Babak ◽  
Pavel Kulich ◽  
Petr Kralik
Keyword(s):  
Biofilm Formation ◽  
Protein A ◽  
Surface Proteins ◽  
Bacterial Cells ◽  
Abiotic Surfaces ◽  
Immunoglobulin Binding Protein ◽  
Chloramine T ◽  
Nucleic Acid Stain ◽  
Immunoglobulin Binding ◽  
Sublethal Concentrations

Sublethal concentrations (sub-MICs) of certain disinfectants are no longer effective in removing biofilms from abiotic surfaces and can even promote the formation of biofilms. Bacterial cells can probably adapt to these low concentrations of disinfectants and defend themselves by way of biofilm formation. In this paper, we report on threeStaphylococcus aureusbiofilm formers (strong B+++, moderate B++, and weak B+) that were cultivated with sub-MICs of commonly used disinfectants, ethanol or chloramine T, and quantified using Syto9 green fluorogenic nucleic acid stain. We demonstrate that 1.25–2.5% ethanol and 2500 μg/mL chloramine T significantly enhancedS. aureusbiofilm formation. To visualize differences in biofilm compactness betweenS. aureusbiofilms in control medium, 1.25% ethanol, or 2500 μg/mL chloramine T, scanning electron microscopy was used. To describe changes in abundance of surface-exposed proteins in ethanol- or chloramine T-treated biofilms, surface proteins were prepared using a novel trypsin shaving approach and quantified after dimethyl labeling by LC-LTQ/Orbitrap MS. Our data show that some proteins with adhesive functions and others with cell maintenance functions and virulence factor EsxA were significantly upregulated by both treatments. In contrast, immunoglobulin-binding protein A was significantly downregulated for both disinfectants. Significant differences were observed in the effect of the two disinfectants on the expression of surface proteins including some adhesins, foldase protein PrsA, and two virulence factors.

scholarly journals Biofilm in dermatology

2019 ◽  
Vol 1 ◽  
pp. 3-7 ◽  
Author(s):  
Kambiam Veettil Vaishnavi ◽  
Lulua Safar ◽  
Keerankulangara Devi
Keyword(s):  
Molecular Biology ◽  
Antimicrobial Therapy ◽  
Biofilm Formation ◽  
Treatment Options ◽  
Therapeutic Strategies ◽  
Diverse Range ◽  
Unique Challenge ◽  
Culture Techniques ◽  
Novel Treatment ◽  
Abiotic Surfaces

Biofilms represent densely packed aggregates of microorganisms encased in a self-produced matrix of extracellular polymeric substance, helping in their attachment to biotic and abiotic surfaces conferring them survival advantage in unfavorable conditions. The stages in biofilm formation are complex, the knowledge of which is important as their role in a diverse range of dermatological diseases is being constantly unraveled. Due to their chronic persistent nature, inability of routine culture techniques to detect them and their resistance to standard antimicrobial therapy, they pose a unique challenge to the treating clinician. Although various novel treatment options are available, they show varying degrees of efficacy and the eradication of biofilm in cutaneous diseases still remains enigmatic. Hence, better understanding of their molecular biology, pathogenesis, and role in various diseases can help in the development of potential therapeutic strategies against biofilms in the future.

Plant mitochondrial protein import: the ins and outs

2018 ◽  
Vol 475 (13) ◽  
pp. 2191-2208 ◽  
Author(s):  
Abi S. Ghifari ◽  
Mabel Gill-Hille ◽  
Monika W. Murcha
Keyword(s):  
Protein Import ◽  
Current Knowledge ◽  
Mitochondrial Protein ◽  
In Planta ◽  
Mitochondrial Protein Import ◽  
Diverse Range ◽  
Mitochondrial Proteome ◽  
Associated Proteins ◽  
Range Of Functions ◽  
Higher Eukaryotes

The majority of the mitochondrial proteome, required to fulfil its diverse range of functions, is cytosolically synthesised and translocated via specialised machinery. The dedicated translocases, receptors, and associated proteins have been characterised in great detail in yeast over the last several decades, yet many of the mechanisms that regulate these processes in higher eukaryotes are still unknown. In this review, we highlight the current knowledge of mitochondrial protein import in plants. Despite the fact that the mechanisms of mitochondrial protein import have remained conserved across species, many unique features have arisen in plants to encompass the developmental, tissue-specific, and stress-responsive regulation in planta. An understanding of unique features and mechanisms in plants provides us with a unique insight into the regulation of mitochondrial biogenesis in higher eukaryotes.

Antibiotics Application Strategies to Control Biofilm Formation in Pathogenic Bacteria

2020 ◽  
Vol 21 (4) ◽  
pp. 270-286 ◽  
Author(s):  
Fazlurrahman Khan ◽  
Dung T.N. Pham ◽  
Sandra F. Oloketuyi ◽  
Young-Mog Kim
Keyword(s):  
Biofilm Formation ◽  
Pathogenic Bacteria ◽  
Extracellular Polymeric Substances ◽  
Quorum Quenching ◽  
Resistance Mechanisms ◽  
Bacterial Biofilm ◽  
Bacterial Cells ◽  
High Concentration ◽  
Biofilm Inhibition ◽  
Abiotic Surfaces

Background: The establishment of a biofilm by most pathogenic bacteria has been known as one of the resistance mechanisms against antibiotics. A biofilm is a structural component where the bacterial community adheres to the biotic or abiotic surfaces by the help of Extracellular Polymeric Substances (EPS) produced by bacterial cells. The biofilm matrix possesses the ability to resist several adverse environmental factors, including the effect of antibiotics. Therefore, the resistance of bacterial biofilm-forming cells could be increased up to 1000 times than the planktonic cells, hence requiring a significantly high concentration of antibiotics for treatment. Methods: Up to the present, several methodologies employing antibiotics as an anti-biofilm, antivirulence or quorum quenching agent have been developed for biofilm inhibition and eradication of a pre-formed mature biofilm. Results: Among the anti-biofilm strategies being tested, the sub-minimal inhibitory concentration of several antibiotics either alone or in combination has been shown to inhibit biofilm formation and down-regulate the production of virulence factors. The combinatorial strategies include (1) combination of multiple antibiotics, (2) combination of antibiotics with non-antibiotic agents and (3) loading of antibiotics onto a carrier. Conclusion: The present review paper describes the role of several antibiotics as biofilm inhibitors and also the alternative strategies adopted for applications in eradicating and inhibiting the formation of biofilm by pathogenic bacteria.

scholarly journals Motility activity, slime production, biofilm formation and genetic typing by ERIC-PCR for Pseudomonas aeruginosa strains isolated from bovine and other sources (human and environment)

2014 ◽  
Vol 17 (2) ◽  
pp. 321-329 ◽  
Author(s):  
K. Wolska ◽  
P. Szweda ◽  
K. Lada ◽  
E. Rytel ◽  
K. Gucwa ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Bovine Mastitis ◽  
Twitching Motility ◽  
Phenotypic Properties ◽  
Biofilm Production ◽  
Abiotic Surfaces ◽  
Hospital Patients ◽  
Relationship Of ◽  
Initial Biofilm ◽  
Different Sources

AbstractThe molecular-typing strategy, ERIC-PCR was used in an attempt to determine the genomic relationship of 28 P. aeruginosa strains isolated from faeces of healthy bovine, bovine mastitis and from faeces of hospital patients as well as from environment. ERIC-PCR fingerprinting revealed large molecular differentiation within this group of isolates. Twenty two out of 28 strains tested generated unique patterns of DNA bands and only three genotypes consisted of two isolates each were identified. We also tested the P. aeruginosa isolates for their ability to form a biofilm on abiotic surfaces including polyvinylchloride and polystyrene. Different biofilm-forming abilities were demonstrated among strains; however, most of them (64.3%) showed moderate-biofilm forming ability. The strains with increased swimming and twitching motility displayed elevated biofilm formation. However, a negative correlation was found between slime and initial biofilm production. On the basis of the results obtained, we suggest that there are no major differences in phenotypic properties between P. aeruginosa strains isolated from different sources

scholarly journals Immune response of calves inoculated with proteins ofAnaplasma marginale bound to an immunostimulant complex

2013 ◽  
Vol 22 (2) ◽  
pp. 253-259 ◽  
Author(s):  
Marcela Ribeiro Gasparini ◽  
Rafael Felipe da Costa Vieira ◽  
Denise Amaral Gomes do Nascimento ◽  
João Luis Garcia ◽  
Odilon Vidotto ◽  
...  
Keyword(s):  
Immune Response ◽  
Current Knowledge ◽  
Surface Proteins ◽  
Control Group ◽  
Humoral Immune ◽  
The Third ◽  
Additional Testing ◽  
Major Surface Proteins ◽  
Cattle Herds ◽  
Major Surface

Despite our current knowledge of the immunology, pathology, and genetics of Anaplasma marginale, prevention in cattle is currently based on old standbys, including live attenuated vaccines, antibiotic treatment, and maintaining enzootic stability in cattle herds. In the present study, we evaluated the use of an immunostimulant complex (ISCOMATRIX) adjuvant, associated with a pool of recombinant major surface proteins (rMSP1a, rMSP1b, rMSP4 and rMSP5) to improve the humoral immune response triggered in calves mainly by IgG2. Ten calves were divided in three groups: 4 calves were inoculated with the ISCOMATRIX/rMSPs (G1); 2 calves were inoculated with ISCOMATRIX adjuvant (G2); and 4 calves received saline (G3). Three inoculations were administered at 21-day intervals. In G1, the calves showed significant increases in total IgG, IgG1 and IgG2 levels 21 days after the second inoculation, compared to the control group (p < 0.05), and G1 calves remained above the cut-off value 28 days after the third inoculation (p < 0.05). The post-immunized sera from calves in G1 reacted specifically for each of the rMSPs used. In conclusion, the ISCOMATRIX/rMSPs induced antigen-specific seroconversion in calves. Therefore, additional testing to explore the protection induced by rMSPs, both alone and in conjunction with proteins previously identified as subdominant epitopes, is warranted.

scholarly journals Extracellular DNA release from the genome-reduced pathogen Mycoplasma hyopneumoniae is essential for biofilm formation on abiotic surfaces

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Benjamin B. A. Raymond ◽  
Cheryl Jenkins ◽  
Lynne Turnbull ◽  
Cynthia B. Whitchurch ◽  
Steven P. Djordjevic
Keyword(s):  
Biofilm Formation ◽  
Mycoplasma Hyopneumoniae ◽  
Extracellular Dna ◽  
Abiotic Surfaces ◽  
Dna Release

scholarly journals Genetic Analysis of Functions Involved in Adhesion of Pseudomonas putida to Seeds

2000 ◽  
Vol 182 (9) ◽  
pp. 2363-2369 ◽  
Author(s):  
Manuel Espinosa-Urgel ◽  
Amparo Salido ◽  
Juan-Luis Ramos
Keyword(s):  
Pseudomonas Putida ◽  
Calcium Binding ◽  
Efflux Pump ◽  
Protein A ◽  
Surface Proteins ◽  
Peptide Transporter ◽  
Multidrug Efflux Pump ◽  
Bacterial Populations ◽  
Abiotic Surfaces ◽  
Initial Seed

ABSTRACT Many agricultural uses of bacteria require the establishment of efficient bacterial populations in the rhizosphere, for which colonization of plant seeds often constitutes a critical first step.Pseudomonas putida KT2440 is a strain that colonizes the rhizosphere of a number of agronomically important plants at high population densities. To identify the functions involved in initial seed colonization by P. putida KT2440, we subjected this strain to transposon mutagenesis and screened for mutants defective in attachment to corn seeds. Eight different mutants were isolated and characterized. While all of them showed reduced attachment to seeds, only two had strong defects in their adhesion to abiotic surfaces (glass and different plastics). Sequences of the loci affected in all eight mutants were obtained. None of the isolated genes had previously been described in P. putida, although four of them showed clear similarities with genes of known functions in other organisms. They corresponded to putative surface and membrane proteins, including a calcium-binding protein, a hemolysin, a peptide transporter, and a potential multidrug efflux pump. One other showed limited similarities with surface proteins, while the remaining three presented no obvious similarities with known genes, indicating that this study has disclosed novel functions.

scholarly journals A Genomic Distance Based on MUM Indicates Discontinuity between Most Bacterial Species and Genera

2008 ◽  
Vol 191 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Marc Deloger ◽  
Meriem El Karoui ◽  
Marie-Agnès Petit
Keyword(s):  
Dna Sequences ◽  
Dna Content ◽  
Core Genome ◽  
Biological Diversity ◽  
Bacterial Species ◽  
Genomic Distance ◽  
The Core ◽  
Intraspecies Diversity ◽  
Genome Level ◽  
Definition Of

ABSTRACT The fundamental unit of biological diversity is the species. However, a remarkable extent of intraspecies diversity in bacteria was discovered by genome sequencing, and it reveals the need to develop clear criteria to group strains within a species. Two main types of analyses used to quantify intraspecies variation at the genome level are the average nucleotide identity (ANI), which detects the DNA conservation of the core genome, and the DNA content, which calculates the proportion of DNA shared by two genomes. Both estimates are based on BLAST alignments for the definition of DNA sequences common to the genome pair. Interestingly, however, results using these methods on intraspecies pairs are not well correlated. This prompted us to develop a genomic-distance index taking into account both criteria of diversity, which are based on DNA maximal unique matches (MUM) shared by two genomes. The values, called MUMi, for MUM index, correlate better with the ANI than with the DNA content. Moreover, the MUMi groups strains in a way that is congruent with routinely used multilocus sequence-typing trees, as well as with ANI-based trees. We used the MUMi to determine the relatedness of all available genome pairs at the species and genus levels. Our analysis reveals a certain consistency in the current notion of bacterial species, in that the bulk of intraspecies and intragenus values are clearly separable. It also confirms that some species are much more diverse than most. As the MUMi is fast to calculate, it offers the possibility of measuring genome distances on the whole database of available genomes.

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