Capsular Polysaccharide Interferes with Biofilm Formation byPasteurella multocidaSerogroup A

ABSTRACTPasteurella multocidais an important multihost animal and zoonotic pathogen that is capable of causing respiratory and multisystemic diseases, bacteremia, and bite wound infections. The glycosaminoglycan capsule ofP. multocidais an essential virulence factor that protects the bacterium from host defenses. However, chronic infections (such as swine atrophic rhinitis and the carrier state in birds and other animals) may be associated with biofilm formation, which has not been characterized inP. multocida. Biofilm formation by clinical isolates was inversely related to capsule production and was confirmed with capsule-deficient mutants of highly encapsulated strains. Capsule-deficient mutants formed biofilms with a larger biomass that was thicker and smoother than the biofilm of encapsulated strains. Passage of a highly encapsulated, poor-biofilm-forming strain under conditions that favored biofilm formation resulted in the production of less capsular polysaccharide and a more robust biofilm, as did addition of hyaluronidase to the growth medium of all of the strains tested. The matrix material of the biofilm was composed predominately of a glycogen exopolysaccharide (EPS), as determined by gas chromatography-mass spectrometry, nuclear magnetic resonance, and enzymatic digestion. However, a putative glycogen synthesis locus was not differentially regulated when the bacteria were grown as a biofilm or planktonically, as determined by quantitative reverse transcriptase PCR. Therefore, the negatively charged capsule may interfere with biofilm formation by blocking adherence to a surface or by preventing the EPS matrix from encasing large numbers of bacterial cells. This is the first detailed description of biofilm formation and a glycogen EPS byP. multocida.IMPORTANCEPasteurella multocidais an important pathogen responsible for severe infections in food animals, domestic and wild birds, pet animals, and humans.P. multocidawas first isolated by Louis Pasteur in 1880 and has been studied for over 130 years. However, aspects of its lifecycle have remained unknown. Although formation of a biofilm byP. multocidahas been proposed, this report is the first to characterize biofilm formation byP. multocida. Of particular interest is that the biofilm matrix material contained a newly reported amylose-like glycogen as the exopolysaccharide component and that production of capsular polysaccharide (CPS) was inversely related to biofilm formation. However, even highly mucoid, poor-biofilm-forming strains could form abundant biofilms by loss of CPS or followingin vitropassage under biofilm growth conditions. Therefore, the carrier state or subclinical chronic infections withP. multocidamay result from CPS downregulation with concomitant enhanced biofilm formation.

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Erratum for Petruzzi et al., “Capsular Polysaccharide Interferes with Biofilm Formation by Pasteurella multocida Serogroup A”

mBio ◽

10.1128/mbio.00176-18 ◽

2018 ◽

Vol 9 (1) ◽

Author(s):

Briana Petruzzi ◽

Robert E. Briggs ◽

Fred M. Tatum ◽

W. Edward Swords ◽

Cristina De Castro ◽

...

Keyword(s):

Biofilm Formation ◽

Pasteurella Multocida ◽

Capsular Polysaccharide

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Phage φAB6-Borne Depolymerase Combats Acinetobacter baumannii Biofilm Formation and Infection

Antibiotics ◽

10.3390/antibiotics10030279 ◽

2021 ◽

Vol 10 (3) ◽

pp. 279

Author(s):

Md. Shahed-Al-Mahmud ◽

Rakesh Roy ◽

Febri Gunawan Sugiokto ◽

Md. Nazmul Islam ◽

Ming-Der Lin ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Biofilm Formation ◽

Bacterial Infections ◽

Capsular Polysaccharide ◽

Foley Catheter ◽

Inhibition Zone ◽

Control Group ◽

Bacterial Cells ◽

Bacterial Lawn

Biofilm formation is one of the main causes of increased antibiotic resistance in Acinetobacter baumannii infections. Bacteriophages and their derivatives, such as tail proteins with depolymerase activity, have shown considerable potential as antibacterial or antivirulence agents against bacterial infections. Here, we gained insights into the activity of a capsular polysaccharide (CPS) depolymerase, derived from the tailspike protein (TSP) of φAB6 phage, to degrade A. baumannii biofilm in vitro. Recombinant TSP showed enzymatic activity and was able to significantly inhibit biofilm formation and degrade formed biofilms; as low as 0.78 ng, the inhibition zone can still be formed on the bacterial lawn. Additionally, TSP inhibited the colonization of A. baumannii on the surface of Foley catheter sections, indicating that it can be used to prevent the adhesion of A. baumannii to medical device surfaces. Transmission and scanning electron microscopy demonstrated membrane leakage of bacterial cells treated with TSP, resulting in cell death. The therapeutic effect of TSP in zebrafish was also evaluated and the results showed that the survival rate was significantly improved (80%) compared with that of the untreated control group (10%). Altogether, we show that TSP derived from φAB6 is expected to become a new antibiotic against multi-drug resistant A. baumannii and a biocontrol agent that prevents the formation of biofilms on medical devices.

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Multi-targeted Antisense Oligonucleotide Delivery by a Framework Nucleic Acid for Inhibiting Biofilm Formation and Virulence

Nano-Micro Letters ◽

10.1007/s40820-020-0409-3 ◽

2020 ◽

Vol 12 (1) ◽

Cited By ~ 5

Author(s):

Yuxin Zhang ◽

Xueping Xie ◽

Wenjuan Ma ◽

Yuxi Zhan ◽

Chenchen Mao ◽

...

Keyword(s):

Nucleic Acid ◽

Antisense Oligonucleotide ◽

Biofilm Formation ◽

Extracellular Polysaccharides ◽

Nucleic Acid Delivery ◽

Bacterial Cells ◽

Chronic Infections ◽

Tetrahedral Configuration ◽

Biofilm Thickness ◽

Targeted Inhibition

AbstractBiofilm formation is responsible for numerous chronic infections and represents a serious health challenge. Bacteria and the extracellular polysaccharides (EPS) cause biofilms to become adherent, toxic, resistant to antibiotics, and ultimately difficult to remove. Inhibition of EPS synthesis can prevent the formation of bacterial biofilms, reduce their robustness, and promote removal. Here, we have developed a framework nucleic acid delivery system with a tetrahedral configuration. It can easily access bacterial cells and functions by delivering antisense oligonucleotides that target specific genes. We designed antisense oligonucleotide sequences with multiple targets based on conserved regions of the VicK protein-binding site. Once delivered to bacterial cells, they significantly decreased EPS synthesis and biofilm thickness. Compared to existing approaches, this system is highly efficacious because it simultaneously reduces the expression of all targeted genes (gtfBCD, gbpB, ftf). We demonstrate a novel nucleic acid-based nanomaterial with multi-targeted inhibition that has great potential for the treatment of chronic infections caused by biofilms.

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Comparative genomics of the Pasteurella multocida toxin

Genome ◽

10.1139/gen-2020-0176 ◽

2021 ◽

Author(s):

Shivakumara Siddaramappa

Keyword(s):

Pasteurella Multocida ◽

Capsular Polysaccharide ◽

Bacterial Species ◽

Atrophic Rhinitis ◽

Type Ii ◽

Nucleotide Polymorphisms ◽

Modification System ◽

Restriction Modification System ◽

Heat Labile ◽

Restriction Modification

Pasteurella multocida is a zoonotic pathogen whose genetic heterogeneity is well known. Five serogroups and 16 serotypes of P. multocida have been recognized thus far based on capsular polysaccharide typing and lipopolysaccharide typing, respectively. Progressive atrophic rhinitis in domestic pigs is caused by P. multocida strains containing toxA, which encodes a heat-labile toxin. In this study, by comparative analyses of the genomes of many strains, it has been shown that toxA is sparsely distributed in P. multocida. Furthermore, full-length homologs of P. multocida toxA were found only in two other bacterial species. It has also been shown that toxA is usually associated with a prophage. Among the toxA-containing prophages that were compared, an operon putatively encoding a type II restriction-modification system was present only in strains LFB3, HN01, and HN06. These results indicate that the selection and maintenance of the heat-labile toxin and the type II restriction-modification system are evolutionarily less favorable among P. multocida strains. Phylogenetic analysis using the alignment- and parameter-free method CVTree3 showed that deduced proteome sequences can be used as effectively as whole/core genome single nucleotide polymorphisms to group P. multocida strains in relation to their serotypes and/or genotypes.

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Differences among clinical isolates of Pseudomonas aeruginosa in their capability of forming biofilms and their susceptibility to antibiotics

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d200538 ◽

2019 ◽

Vol 20 (5) ◽

Author(s):

DIDIK WAHYUDI ◽

ABU THOLIB AMAN ◽

NIKEN SATUTI NUR HANDAYANI ◽

ENDANG SUTARININGSIH SOETARTO

Keyword(s):

Pseudomonas Aeruginosa ◽

Biofilm Formation ◽

Test Method ◽

Clinical Isolates ◽

Gene Identification ◽

Bacterial Cells ◽

Bacterial Identification ◽

Chronic Infections ◽

Automatic Equipment ◽

Polymerase Chain

Abstract. Wahyudi D, Aman AT, Handayani NSN, Soetarto ES. 2019. Differences among clinical isolates of Pseudomonas aeruginosa in their capability of forming biofilms and their susceptibility to antibiotics. Biodiversitas 20: 1450-1456. Pseudomonas aeruginosa is an important nosocomial pathogen capable of causing both acute and chronic infections. The individuals of this bacterium have differences in their capability of forming biofilms. Biofilm is a collection of bacterial cells attached to the tissue, coated by polysaccharides and extracellular matrix, enabling bacteria to become resistant to antibiotics, so infection is difficult to treat. The aim of this study was to know the differences among clinical isolates of Pseudomonas aeruginosa in their capability of forming biofilms, and their susceptibility to some antibiotics. The bacteria were isolated from various patient samples at Dr. Moewardi Hospital Surakarta, Indonesia, from August to December 2017. The isolates were purified using single cell colony technique. The bacterial identification and tests of susceptibility to many antibiotic were conducted using automatic equipment (vitex® 2). Test method of biofilm formation was done using the Tissue Culture Plate. The readings of results were monitored spectrophotometrically at a wavelength of 570 nm and repeated 8 times. DNA isolation was done using Qiagen DNeasy Blood and Tissue Kit, and gene identification (pelD and pslA) was done using PCR (Polymerase Chain Reaction) and visualization through electrophoresis. The results showed that of the 64 isolates of P. aeruginosa from blood, sputum, urine, ear middle, urine catheter, pleural fluid, pus, stool, aspirate, and cerebrospinal, 22% were low in forming biofilm, 50% moderate, and 28% high. Isolates of P. aeruginosa were resistant to ampicillin, cefazolin, tigecycline, nirofurantoin, and cotrimoxazole, but sensitive to piperacillin, ceftazidime, cefepime, aztreonam, meropenem, amikacin, gentamicin, and ciprofloxacin. The genes of pelD and pslA were present in all P. aeruginosa isolates (low, moderate, dan high). In conclusion, P. aeruginosa clinical isolates had different capability of forming biofilms and susceptibility to antibiotics. Isolates having high ability to form biofilm were relatively more resistant to many antibiotics. They were most sensitive to amikacin and resistant to ampicillin. There was no difference in the presence of mop pelD and pslA among all isolates.

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Signal Sensing and Transduction Are Conserved between the Periplasmic Sensory Domains of BifA and SagS

mSphere ◽

10.1128/msphere.00442-19 ◽

2019 ◽

Vol 4 (4) ◽

Author(s):

Jozef Dingemans ◽

Rebecca E. Al-Feghali ◽

Holger Sondermann ◽

Karin Sauer

Keyword(s):

Pseudomonas Aeruginosa ◽

Biofilm Formation ◽

Structural Similarity ◽

Opportunistic Pathogen ◽

Sequence Conservation ◽

Sensor Kinase ◽

Antibiotic Tolerance ◽

Bacterial Cells ◽

Chronic Infections ◽

Content Type

ABSTRACT The hybrid sensor kinase SagS of Pseudomonas aeruginosa plays a key role in the transition from the planktonic to the biofilm mode of growth. Recently, we have shown that distinct sets of residues in its periplasmic HmsP sensory domain are involved in the regulation of biofilm formation or antibiotic tolerance. Interestingly, the HmsP domain of the phosphodiesterase BifA shows great predicted structural similarity to that of SagS, despite moderate sequence conservation and only a number of residues involved in SagS signaling being conserved between both proteins. Based on this observation, we hypothesized that BifA and SagS may use similar mechanisms to sense and transduce signals perceived at their periplasmic HmsP domains and, therefore, may be interchangeable. To test this hypothesis, we constructed SagS hybrids in which the HmsP domain of SagS was replaced by that of BifA (and vice versa) or by the DISMED2 sensory domain of NicD. The SagS-BifA hybrid restored attachment and biofilm formation by the ΔbifA mutant. Likewise, while the NicD-SagS hybrid was nonfunctional, the BifA-SagS hybrid partially restored pathways leading to biofilm formation and antibiotic tolerance in a ΔsagS mutant background. Furthermore, alanine substitution of key residues previously associated with the biofilm formation and antibiotic tolerance pathways of SagS impaired signal transduction by the BifA-SagS hybrid in a similar way to SagS. In conclusion, our data indicate that the nature of the sensory domain is important for proper functionality of the cytoplasmic effector domains and that signal sensing and transduction are likely conserved in SagS and BifA. IMPORTANCE Biofilms have been associated with more than 60% of all recalcitrant and chronic infections and can render bacterial cells up to a thousand times more resistant to antibiotics than planktonic cells. Although it is known that the transition from the planktonic to the biofilm mode of growth involves two-component regulatory systems, increased c-di-GMP levels, and quorum sensing systems among others, the exact signaling events that lead to biofilm formation remain unknown. In the opportunistic pathogen Pseudomonas aeruginosa, the hybrid sensor kinase SagS regulates biofilm formation and antibiotic tolerance through two independent pathways via distinct residues in its periplasmic sensory domain. Interestingly, the sensory domains of SagS and BifA show great predicted structural similarity despite moderate sequence conservation. Here we show that the sensory domains of BifA and SagS are functionally interchangeable and that they use a similar mechanism of signal sensing and transduction, which broadens our understanding of how bacteria perceive and transduce signals when transitioning to the biofilm mode of growth.

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Human Host Defense Peptide LL-37 Prevents Bacterial Biofilm Formation

Infection and Immunity ◽

10.1128/iai.00318-08 ◽

2008 ◽

Vol 76 (9) ◽

pp. 4176-4182 ◽

Cited By ~ 343

Author(s):

Joerg Overhage ◽

Andrea Campisano ◽

Manjeet Bains ◽

Ellen C. W. Torfs ◽

Bernd H. A. Rehm ◽

...

Keyword(s):

Host Defense ◽

Biofilm Formation ◽

Model Organism ◽

Critical Factor ◽

Bacterial Biofilm ◽

Bacterial Cells ◽

Chronic Infections ◽

Host Defense Peptide ◽

Biofilm Development

ABSTRACT The ability to form biofilms is a critical factor in chronic infections by Pseudomonas aeruginosa and has made this bacterium a model organism with respect to biofilm formation. This study describes a new, previously unrecognized role for the human cationic host defense peptide LL-37. In addition to its key role in modulating the innate immune response and weak antimicrobial activity, LL-37 potently inhibited the formation of bacterial biofilms in vitro. This occurred at the very low and physiologically meaningful concentration of 0.5 μg/ml, far below that required to kill or inhibit growth (MIC = 64 μg/ml). LL-37 also affected existing, pregrown P. aeruginosa biofilms. Similar results were obtained using the bovine neutrophil peptide indolicidin, but no inhibitory effect on biofilm formation was detected using subinhibitory concentrations of the mouse peptide CRAMP, which shares 67% identity with LL-37, polymyxin B, or the bovine bactenecin homolog Bac2A. Using microarrays and follow-up studies, we were able to demonstrate that LL-37 affected biofilm formation by decreasing the attachment of bacterial cells, stimulating twitching motility, and influencing two major quorum sensing systems (Las and Rhl), leading to the downregulation of genes essential for biofilm development.

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Bioactivity of Phenolic Compounds Extracted from Strawberry against Formation of Pseudomonas aeruginosa Biofilm

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.1.27 ◽

2019 ◽

Vol 10 (01) ◽

Author(s):

Baydaa Hussein ◽

Zainab A. Aldhaher ◽

Shahrazad Najem Abdu-Allah ◽

Adel Hamdan

Keyword(s):

Pseudomonas Aeruginosa ◽

Phenolic Compounds ◽

Biofilm Formation ◽

Opportunistic Infections ◽

Formation Rate ◽

Hydrocarbon Chain ◽

Health Concern ◽

Gas Chromatography Mass Spectrometry ◽

Phenolic Contents

Background: Biofilm is a bacterial way of life prevalent in the world of microbes; in addition to that it is a source of alarm in the field of health concern. Pseudomonas aeruginosa is a pathogenic bacterium responsible for all opportunistic infections such as chronic and severe. Aim of this study: This paper aims to provide an overview of the promotion of isolates to produce a biofilm in vitro under special circumstances, to expose certain antibiotics to produce phenotypic evaluation of biofilm bacteria. Methods and Materials: Three diverse ways were used to inhibited biofilm formation of P.aeruginosa by effect of phenolic compounds extracts from strawberries. Isolates produced biofilm on agar MacConkey under certain circumstances. Results: The results showed that all isolates were resistant to antibiotics except sensitive to azithromycin (AZM, 15μg), and in this study was conducted on three ways to detect the biofilm produced, has been detected by the biofilm like Tissue culture plate (TCP), Tube method (TM), Congo Red Agar (CRA). These methods gave a clear result of these isolates under study. Active compounds were analyzed in both extracts by Gas Chromatography-mass Spectrometry which indicate High molecular weight compound with a long hydrocarbon chain. Conclusion: Phenolic compounds could behave as bioactive material and can be useful to be used in pharmaceutical synthesis. Phenolic contents which found in leaves and fruits extracts of strawberries shows antibacterial activity against all strains tested by the ability to reduce the production of biofilm formation rate.

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Process Description of an Unconventional Biofilm Formation by Bacterial Cells Autoagglutinating Through Sticky, Long, and Peritrichate Nanofibers

10.26434/chemrxiv.10001924.v1 ◽

2019 ◽

Author(s):

Yoshihide Furuichi ◽

Shogo Yoshimoto ◽

Tomohiro Inaba ◽

Nobuhiko Nomura ◽

Katsutoshi Hori

Keyword(s):

Formation Process ◽

Biofilm Formation ◽

Extracellular Polymeric Substances ◽

Waste Treatment ◽

Large Cell ◽

Dlvo Theory ◽

Bacterial Cells ◽

Chemical Production ◽

Discontinuous Surface ◽

Cell Cell

Biofilms are used in environmental biotechnologies including waste treatment and environmentally friendly chemical production. Understanding the mechanisms of biofilm formation is essential to control microbial behavior and improve environmental biotechnologies. Acinetobacter sp. Tol 5 autoagglutinate through the interaction of the long, peritrichate nanofiber protein AtaA, a trimeric autotransporter adhesin. Using AtaA, without cell growth or the production of extracellular polymeric substances, Tol 5 cells quickly form an unconventional biofilm. In this study, we investigated the formation process of this unconventional biofilm, which started with cell–cell interactions, proceeded to cell clumping, and led to the formation of large cell aggregates. The cell–cell interaction was described by DLVO theory based on a new concept, which considers two independent interactions between two cell bodies and between two AtaA fiber tips forming a virtual discontinuous surface. If cell bodies cannot collide owing to an energy barrier at low ionic strengths but approach within the interactive distance of AtaA fibers, cells can agglutinate through their contact. Cell clumping proceeds following the cluster–cluster aggregation model, and an unconventional biofilm containing void spaces and a fractal nature develops. Understanding its formation process would extend the utilization of various types of biofilms, enhancing environmental biotechnologies.

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Antibiotics Application Strategies to Control Biofilm Formation in Pathogenic Bacteria

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666191112155905 ◽

2020 ◽

Vol 21 (4) ◽

pp. 270-286 ◽

Cited By ~ 2

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.

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