scholarly journals Use of a stainless steel washer platform to study Acinetobacter baumannii adhesion and biofilm formation on abiotic surfaces

Microbiology ◽  
2013 ◽  
Vol 159 (Pt_12) ◽  
pp. 2594-2604 ◽  
Author(s):  
Samantha J. Orsinger-Jacobsen ◽  
Shenan S. Patel ◽  
Ernestine M. Vellozzi ◽  
Phillip Gialanella ◽  
Leonardo Nimrichter ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Abiotic Surfaces

Attachment to and biofilm formation on abiotic surfaces by Acinetobacter baumannii: involvement of a novel chaperone-usher pili assembly system

Microbiology ◽  
2003 ◽  
Vol 149 (12) ◽  
pp. 3473-3484 ◽  
Author(s):  
Andrew P. Tomaras ◽  
Caleb W. Dorsey ◽  
Richard E. Edelmann ◽  
Luis A. Actis
Keyword(s):  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Prototype Strain ◽  
Culture Conditions ◽  
Sequencing Analysis ◽  
Cell Aggregates ◽  
Surface Attachment ◽  
Abiotic Surfaces ◽  
Air Interface ◽  
Dna Sequencing Analysis

Acinetobacter baumannii causes severe infections in compromised patients, survives on abiotic surfaces in hospital environments and colonizes different medical devices. In this study the analysis of the processes involved in surface attachment and biofilm formation by the prototype strain 19606 was initiated. This strain attaches to and forms biofilm structures on plastic and glass surfaces, particularly at the liquid–air interface of cultures incubated stagnantly. The cell aggregates, which contain cell stacks separated by water channels, formed under different culture conditions and were significantly enhanced under iron limitation. Electron and fluorescence microscopy showed that pili and exopolysaccharides are part of the cell aggregates formed by this strain. Electron microscopy of two insertion derivatives deficient in attachment and biofilm formation revealed the disappearance of pili-like structures and DNA sequencing analysis showed that the transposon insertions interrupted genes with the highest similarity to hypothetical genes found in Pseudomonas aeruginosa, Pseudomonas putida and Vibrio parahaemolyticus. Although the products of these genes, which have been named csuC and csuE, have no known functions, they are located within a polycistronic operon that includes four other genes, two of which encode proteins related to chaperones and ushers involved in pili assembly in other bacteria. Introduction of a copy of the csuE parental gene restored the adherence phenotype and the presence of pili on the cell surface of the csuE mutant, but not that of the csuC derivative. These results demonstrate that the expression of a chaperone-usher secretion system, some of whose components appear to be acquired from unrelated sources, is required for pili formation and the concomitant attachment to plastic surfaces and the ensuing formation of biofilms by A. baumannii cells.

scholarly journals Imipenem Treatment Induces Expression of Important Genes and Phenotypes in a Resistant Acinetobacter baumannii Isolate

2015 ◽  
Vol 60 (3) ◽  
pp. 1370-1376 ◽  
Author(s):  
Ghulam Nasser Dhabaan ◽  
Sazaly AbuBakar ◽  
Gustavo Maia Cerqueira ◽  
Mohammed Al-Haroni ◽  
Sui Ping Pang ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Clinical Success ◽  
Multidrug Resistant ◽  
Type Iv Pili ◽  
Control Measures ◽  
Content Type ◽  
Type Iv ◽  
Abiotic Surfaces ◽  
Colonization Factors

Acinetobacter baumanniihas emerged as a notorious multidrug-resistant pathogen, and development of novel control measures is of the utmost importance. Understanding the factors that play a role in drug resistance may contribute to the identification of novel therapeutic targets. Pili are essential forA. baumanniiadherence to and biofilm formation on abiotic surfaces as well as virulence. In the present study, we found that biofilm formation was significantly induced in an imipenem-resistant (Impr) strain treated with a subinhibitory concentration of antibiotic compared to that in an untreated control and an imipenem-susceptible (Imps) isolate. Using microarray and quantitative PCR analyses, we observed that several genes responsible for the synthesis of type IV pili were significantly upregulated in the Imprbut not in the Impsisolate. Notably, this finding is corroborated by an increase in the motility of the Imprstrain. Our results suggest that the ability to overproduce colonization factors in response to imipenem treatment confers biological advantage toA. baumanniiand may contribute to clinical success.

scholarly journals The Acinetobacter baumannii Biofilm-Associated Protein Plays a Role in Adherence to Human Epithelial Cells

2011 ◽  
Vol 80 (1) ◽  
pp. 228-233 ◽  
Author(s):  
Kari A. Brossard ◽  
Anthony A. Campagnari
Keyword(s):  
Epithelial Cells ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Bacterial Colonization ◽  
Water Channel ◽  
Cell Surface Hydrophobicity ◽  
Health Care Facilities ◽  
Content Type ◽  
Abiotic Surfaces ◽  
Normal Human

ABSTRACTAcinetobacter baumanniiis a significant source of nosocomial infections worldwide. This bacterium has the ability to survive and persist on multiple abiotic surfaces in health care facilities, and once a focus has been established, this opportunistic pathogen is difficult to eradicate. This paper demonstrates that theA. baumanniibiofilm-associated protein (Bap) is necessary for mature biofilm formation on medically relevant surfaces, including polypropylene, polystyrene, and titanium. Scanning electron microscopy analyses of biofilms show that Bap is required for three-dimensional tower structure and water channel formation. In conjunction with persistence on abiotic surfaces, adherence to eukaryotic cells is an important step in bacterial colonization resulting in infection of the host. We have described Bap as the surface structure involved in adherence ofA. baumanniito both normal human bronchial epithelial cells and normal human neonatal keratinocytes. However, Bap is not involved in internalization of the bacterium in these two cell lines. Furthermore, this study shows that the presence of Bap increases the bacterial cell surface hydrophobicity. The results of this study are pertinent, as the data lead to a better understanding of the role of Bap in biofilm formation on medical surfaces and in colonization of the host.

scholarly journals Microbicides Alter the Expression and Function of RND-Type Efflux Pump AdeABC in Biofilm-Associated Cells of Acinetobacter baumannii Clinical Isolates

2015 ◽  
Vol 60 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Suvarna Krishnamoorthy ◽  
Bhavikkumar P. Shah ◽  
Hiu Ham Lee ◽  
Luis R. Martinez
Keyword(s):  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Efflux Pump ◽  
Acquired Resistance ◽  
Multidrug Resistant ◽  
Clinical Isolates ◽  
Content Type ◽  
Abiotic Surfaces ◽  
Hospital Environments ◽  
And Function

ABSTRACTAcinetobacter baumanniiis a Gram-negative bacterium that causes nosocomial infections worldwide. This microbe's propensity to form biofilms allows it to persist and to survive on clinical abiotic surfaces for long periods. In fact,A. baumanniibiofilm formation and its multidrug-resistant nature severely compromise our capacity to care for patients in hospital environments. In contrast, microbicides such as cetrimide (CT) and chlorhexidine (CHX) play important roles in the prevention and treatment of infections. We assessed the efficacy of CT and CHX, either alone or in combination, in eradicatingA. baumanniibiofilms formed by clinical isolates, by using stainless steel washers to mimic hard abiotic surfaces found in hospital settings. We demonstrated that increasing amounts of each microbicide, alone or in combination, were able to damage and to reduce the viability ofA. baumanniibiofilms efficaciously. Interestingly, theadeBgene of the resistance-nodulation-cell division (RND) family is predominantly associated with acquired resistance to antimicrobials inA. baumannii. We showed that CT and CHX adversely modified the expression and function of the RND-type efflux pump AdeABC in biofilm-associatedA. baumanniicells. Furthermore, we established that these microbicides decreased the negative charges onA. baumanniicell membranes, causing dysregulation of the efflux pump and leading to cell death. Our findings suggest that CT and CHX, alone or in combination, can be used efficaciously for eradication ofA. baumanniifrom hospital surfaces, in order to reduce infections caused by this nosocomial agent.

scholarly journals Attachment of and Biofilm Formation by Enterobacter sakazakii on Stainless Steel and Enteral Feeding Tubes

2006 ◽  
Vol 72 (9) ◽  
pp. 5846-5856 ◽  
Author(s):  
Hoikyung Kim ◽  
Jee-Hoon Ryu ◽  
Larry R. Beuchat
Keyword(s):  
Stainless Steel ◽  
Infant Formula ◽  
Nutrient Availability ◽  
Enteral Feeding ◽  
Biofilm Formation ◽  
Enterobacter Sakazakii ◽  
Feeding Tubes ◽  
Abiotic Surfaces ◽  
And Storage ◽  
Phosphate Buffered Saline

ABSTRACT Enterobacter sakazakii has been reported to form biofilms, but environmental conditions affecting attachment to and biofilm formation on abiotic surfaces have not been described. We did a study to determine the effects of temperature and nutrient availability on attachment and biofilm formation by E. sakazakii on stainless steel and enteral feeding tubes. Five strains grown to stationary phase in tryptic soy broth (TSB), infant formula broth (IFB), or lettuce juice broth (LJB) at 12 and 25�C were examined for the extent to which they attach to these materials. Higher populations attached at 25�C than at 12�C. Stainless steel coupons and enteral feeding tubes were immersed for 24 h at 4�C in phosphate-buffered saline suspensions (7 log CFU/ml) to facilitate the attachment of 5.33 to 5.51 and 5.03 to 5.12 log CFU/cm2, respectively, before they were immersed in TSB, IFB, or LJB, followed by incubation at 12 or 25�C for up to 10 days. Biofilms were not produced at 12�C. The number of cells of test strains increased by 1.42 to 1.67 log CFU/cm2 and 1.16 to 1.31 log CFU/cm2 in biofilms formed on stainless steel and feeding tubes, respectively, immersed in IFB at 25�C; biofilms were not formed on TSB and LJB at 25�C, indicating that nutrient availability plays a major role in processes leading to biofilm formation on the surfaces of these inert materials. These observations emphasize the importance of temperature control in reconstituted infant formula preparation and storage areas in preventing attachment and biofilm formation by E. sakazakii.

scholarly journals The Acinetobacter baumannii 19606 OmpA Protein Plays a Role in Biofilm Formation on Abiotic Surfaces and in the Interaction of This Pathogen with Eukaryotic Cells

2009 ◽  
Vol 77 (8) ◽  
pp. 3150-3160 ◽  
Author(s):  
Jennifer A. Gaddy ◽  
Andrew P. Tomaras ◽  
Luis A. Actis
Keyword(s):  
Epithelial Cells ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Protein A ◽  
Bacterial Attachment ◽  
Alveolar Epithelial Cells ◽  
Eukaryotic Cells ◽  
Temperature Sensitive ◽  
Alveolar Epithelial ◽  
Abiotic Surfaces

ABSTRACT The ability of Acinetobacter baumannii to adhere to and persist on surfaces as biofilms could be central to its pathogenicity. The production of pili and a biofilm-associated protein and the expression of antibiotic resistance are needed for robust biofilm formation on abiotic and biotic surfaces. This multistep process also depends on the expression of transcriptional regulatory functions, some of which could sense nutrients available to cells. This report extends previous observations by showing that although outer membrane protein A (OmpA) of A. baumannii 19606 plays a partial role in the development of robust biofilms on plastic, it is essential for bacterial attachment to Candida albicans filaments and A549 human alveolar epithelial cells. In contrast to abiotic surfaces, the interaction with biotic surfaces is independent of the CsuA/BABCDE-mediated pili. The interaction of A. baumannii 19606 with fungal and epithelial cells also results in their apoptotic death, a response that depends on the direct contact of bacteria with these two types of eukaryotic cells. Furthermore, the bacterial adhesion phenotype correlates with the ability of bacteria to invade A549 epithelial cells. Interestingly, the killing activity of cell-free culture supernatants proved to be protease and temperature sensitive, suggesting that its cytotoxic activity is due to secreted proteins, some of which are different from OmpA.

scholarly journals Structural basis for Acinetobacter baumannii biofilm formation

2018 ◽  
Vol 115 (21) ◽  
pp. 5558-5563 ◽  
Author(s):  
Natalia Pakharukova ◽  
Minna Tuittila ◽  
Sari Paavilainen ◽  
Henri Malmi ◽  
Olena Parilova ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Medical Devices ◽  
Biofilm Formation ◽  
Bacterial Attachment ◽  
Structural Basis ◽  
Binding Mechanism ◽  
X Ray ◽  
Abiotic Surfaces ◽  
Hospital Environments ◽  
Hydrophilic Materials

Acinetobacter baumannii—a leading cause of nosocomial infections—has a remarkable capacity to persist in hospital environments and medical devices due to its ability to form biofilms. Biofilm formation is mediated by Csu pili, assembled via the “archaic” chaperone–usher pathway. The X-ray structure of the CsuC-CsuE chaperone–adhesin preassembly complex reveals the basis for bacterial attachment to abiotic surfaces. CsuE exposes three hydrophobic finger-like loops at the tip of the pilus. Decreasing the hydrophobicity of these abolishes bacterial attachment, suggesting that archaic pili use tip-fingers to detect and bind to hydrophobic cavities in substrates. Antitip antibody completely blocks biofilm formation, presenting a means to prevent the spread of the pathogen. The use of hydrophilic materials instead of hydrophobic plastics in medical devices may represent another simple and cheap solution to reduce pathogen spread. Phylogenetic analysis suggests that the tip-fingers binding mechanism is shared by all archaic pili carrying two-domain adhesins. The use of flexible fingers instead of classical receptor-binding cavities is presumably more advantageous for attachment to structurally variable substrates, such as abiotic surfaces.

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 Interaction of Acinetobacter baumannii with Human Serum Albumin: Does the Host Determines the Outcome?

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 833
Author(s):  
Camila Pimentel ◽  
Casin Le ◽  
Marisel R. Tuttobene ◽  
Tomas Subils ◽  
Krisztina M. Papp-Wallace ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Human Serum Albumin ◽  
Quorum Sensing ◽  
Serum Albumin ◽  
Human Serum ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Model Systems ◽  
Expression Levels ◽  
Multiple Drugs

Acinetobacter baumannii has become a serious threat to human health due to its extreme antibiotic resistance, environmental persistence, and capacity to survive within the host. Two A. baumannii strains, A118 and AB5075, commonly used as model systems, and three carbapenem-resistant strains, which are becoming ever more dangerous due to the multiple drugs they can resist, were exposed to 3.5% human serum albumin (HSA) and human serum (HS) to evaluate their response with respect to antimicrobial resistance, biofilm formation, and quorum sensing, all features responsible for increasing survival and persistence in the environment and human body. Expression levels of antibiotic resistance genes were modified differently when examined in different strains. The cmlA gene was upregulated or downregulated in conditions of exposure to 3.5% HSA or HS depending on the strain. Expression levels of pbp1 and pbp3 tended to be increased by the presence of HSA and HS, but the effect was not seen in all strains. A. baumannii A118 growing in the presence of HS did not experience increased expression of these genes. Aminoglycoside-modifying enzymes were also expressed at higher or lower levels in the presence of HSA or HS. Still, the response was not uniform; in some cases, expression was enhanced, and in other cases, it was tapered. While A. baumannii AB5075 became more susceptible to rifampicin in the presence of 3.5% HSA or HS, strain A118 did not show any changes. Expression of arr2, a gene involved in resistance to rifampicin present in A. baumannii AMA16, was expressed at higher levels when HS was present in the culture medium. HSA and HS reduced biofilm formation and production of N-Acyl Homoserine Lactone, a compound intimately associated with quorum sensing. In conclusion, HSA, the main component of HS, stimulates a variety of adaptative responses in infecting A. baumannii strains.

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

Sign in / Sign up

Export Citation Format

Share Document