Biofilm formation and serum susceptibility in Pseudomonas aeruginosa

Open Medicine ◽  
2014 ◽  
Vol 9 (2) ◽  
pp. 187-192 ◽  
Author(s):  
Greta Mikucionyte ◽  
Asta Dambrauskiene ◽  
Erika Skrodeniene ◽  
Astra Vitkauskiene

AbstractPseudomonas aeruginosa (P. aeruginosa) is one of the most important opportunistic pathogens. The pathogenicity of P. aeruginosa has been associated with multiple bacterial virulence factors. The aim of this study was to evaluate the association between P. aeruginosa strains obtained from various clinical samples and resistance to antibiotics and pathogenicity factors, such as resistance to serum bactericidal activity and biofilm formation. This study included 121 P. aeruginosa strains isolated from clinical samples; 65 of the isolated P. aeruginosa strains were carbapenem-resistant, and 56 were carbapenem-sensitive. Carbapenem-resistant P. aeruginosa strains were more often resistant to the majority of tested antibiotics, compared to carbapenem-sensitive strains. We did not find any statistically significant difference between resistance to carbapenems and serum resistance and ability of tested P. aeruginosa strains to produce biofilms. Carbapenem-resistant P. aeruginosa strains were recovered from the urinary tract significantly more often (75.0%) than carbapenem-sensitive P. aeruginosa strains (25.0%). Carbapenem-sensitive P. aeruginosa strains were recovered significantly more often from the respiratory tract than carbapenem-resistant strains, 60.0% and 40.0%, respectively. All the P. aeruginosa strains recovered from blood were serum-resistant. P. aeruginosa strains recovered from the respiratory tract and wounds were significantly frequently serum sensitive, 95.6% and 56.6%, respectively. We did not find any differences in biofilm production among the P. aeruginosa strains recovered from different sources.

Biofilms ◽  
2004 ◽  
Vol 1 (2) ◽  
pp. 123-130 ◽  
Author(s):  
R. L. Sammons ◽  
D. Kaur ◽  
P. Neal

The aim of this study was to investigate bacterial survival and biofilm formation on toothbrushes. Fifteen healthy volunteers each used a normal toothbrush and an antibacterial toothbrush of the same design for two separate 5 week periods. Bacteria were removed from the brush head by swabbing and mechanical agitation in 10ml of tryptone soya broth, cultured aerobically on selective and non-selective media, and classified by Gram staining, catalase and oxidase tests. Survival of Staphylococcus epidermidis and Pseudomonas aeruginosa was monitored in the laboratory on both types of brush over 8 days. Scanning electron microscopy was used to observe biofilm formation on antibacterial and conventional brushes used for various times. Numbers of bacteria isolated from conventional and antibacterial brushes from different individuals ranged from 8.3×103 to 4.7×106 and from 1×102 to 1.2×106 colony-forming units/ml, respectively. A larger number of bacteria were isolated from conventional brushes than from antibacterial brushes used by the same individuals but no statistically significant difference was demonstrated. No differences in the relative proportions of Gram-negative and Gram-positive rods or cocci were seen. Staphylococci, presumptive coliforms and pseudomonads were isolated from 48%, 28% and 16% of brushes, respectively. Pseudomonas aeruginosa was viable for at least 4 days on conventional, and 2–3 days on antibacterial, brushes, whilst S. epidermidis survived for 6–8 days on antibacterial and more than 8 days on conventional brushes. Biofilms formed on the heads and bristles of both conventional and antibacterial brushes. Extensive, mixed community biofilms developed after several months of use. We conclude that toothbrushes may be a reservoir of opportunistic pathogens including staphylococci and pseudomonad-like organisms and must be considered as a potential source of haematogenous infections and cross-infection.


2017 ◽  
Vol 66 (4) ◽  
pp. 501-508 ◽  
Author(s):  
Rambha K. Shah ◽  
Zhao H. Ni ◽  
Xiao Y. Sun ◽  
Guo Q. Wang ◽  
Fan Li

Klebsiella pneumoniae strains that are commonly recognized by clinicians and microbiologists are termed as classical K. pneumoniae (cKP). A strain with capsule-associated mucopolysaccharide web is known as hypervirulent K. pneumoniae (hvKP) as it enhances the serum resistant and biofilm production. Aim is to determine and correlate various virulence genes, ESBL, serum bactericidal effect and biofilm formation of clinical isolated cKP and hvKP from respiratory tract infected patients. A total of 96 K. pneumoniae strains were isolated from sputum of respiratory tract infected patients. The isolates were performed string test, AST, ESBL virulence gene, serum bactericidal and biofilm assays. Out of 96 isolates, 39 isolates (40.6%) were identified with hypervirulent phenotypes. The number of cKP exhibiting resistance to the tested antimicrobials and ESBLs were significantly higher than that of the hvKP strains. The virulence genes of K. pneumoniae such as K1, K2, rmpA, uge, kfu and aerobactin were strongly associated with hvKP than cKP. However, no significant difference was found in FIM-1 and MrKD3 genes. ESBL producing cKP and hvKP were significantly associated with strong biofilm formation (both P < 0.05) and highly associated with bactericidal effect of serum (both P < 0.05) than cKP strains. However, neither biofilm formation nor bactericidal effect of serum was found with significant difference in between ESBL producing cKP and ESBL producing hvKP strains (both P > 0.05). Although the hvKP possess more virulence gene, but they didn’t show any significant difference between biofilm formation and bactericidal effect of serum compared with ESBL producing cKP strains.


2019 ◽  
Vol 18 (2) ◽  
pp. 28-34 ◽  
Author(s):  
N. V. Dmitrieva ◽  
M. V. Eidelshtein ◽  
V. V. Aginova ◽  
I. N. Perukhova ◽  
Z. V. Grigorievskaya ◽  
...  

The purpose of the study was to evaluate the frequency of isolation of multi-resistant Pseudomonas aeruginosa and identify the mechanisms of resistance to carbapenems.Material and methods. We analyzed 866 strains of Pseudomonos aeruginosaisolated from clinical samples from cancer patients in the period 2014–2016. the level of resistance to piperacillin/tazobactam, ceftazidime, cefepime, imipenem, meropenem, ciprofloxacin, amikacin in dynamics was determined. carbapenem-resistant (car-R) strains were examined for the presence of enzymes.Results. Between 2014 and 2016, the number of strains resistant to piperacillin/tazobactam was 20.1–12.9 %, to ceftazidime – 33.0–32.9 %, to cefepime – 25.6–32.9 %, ciprofloxacin – 36.8–43.8 %, amikacin – 23.8–24.9 %. No statistically significant differences were found (p>0.05). However, an increase in the number of car-R strains from 31.7 to 43.8 % was observed (p<0.05). of 7 strains of P. aeruginosainvestigated for the presence of acquired carbapenemases, the production of metal-beta-lactamase of group Vimwas detected in 2 strains, and class acarbapenemases of the gEs-5 group in one strain.Conclusion. P. aeruginosaresistance to all antibiotic groups did not exceed 50 % and remained almost unchanged for 3 years, with the exception of the increase in car-R strains. three out of 7 (42.9 %) carbapenem-resistant strains were genetically stable.


Biology ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 287
Author(s):  
Yoshiaki Usui ◽  
Tetsu Shimizu ◽  
Akira Nakamura ◽  
Masahiro Ito

Previously, we reported that the coculture of motile Methylobacterium sp. ME121 and non-motile Kaistia sp. 32K, isolated from the same soil sample, displayed accelerated motility of strain ME121 due to an extracellular polysaccharide (EPS) produced by strain 32K. Since EPS is a major component of biofilms, we aimed to investigate the biofilm formation in cocultures of the two strains. The extent of biofilm formation was measured by a microtiter dish assay with the dye crystal violet. A significant increase in the amount of biofilm was observed in the coculture of the two strains, as compared to that of the monocultures, which could be due to a metabolite produced by strain 32K. However, in the coculture with strain 32K, using Escherichia coli or Pseudomonas aeruginosa, there was no difference in the amount of biofilm formation as compared with the monoculture. Elevated biofilm formation was also observed in the coculture of strain ME121 with Kaistia adipata, which was isolated from a different soil sample. Methylobacterium radiotolerans, isolated from another soil sample, showed a significant increase in biofilm formation when cocultured with K. adipata, but not with strain 32K. We also found that the culture supernatants of strains 32K and K. adipata accelerated the motility of strains ME121 and M. radiotolerans, wherein culture supernatant of K. adipata significantly increased the motility of M. radiotolerans, as compared to that by the culture supernatant of strain 32K. These results indicated that there was a positive relationship between accelerated motility and increased biofilm formation in Methylobacterium spp. This is the first study to report that the metabolites from Kaistia spp. could specifically modulate the biofilm-forming ability of Methylobacterium spp. Methylobacterium spp. biofilms are capable of inhibiting the biofilm formation of mycobacteria, which are opportunistic pathogens that cause problems in infectious diseases. Thus, the metabolites from the culture supernatant of Kaistia spp. have the potential to contribute to the environment in which increased biofilm production of Methylobacterium is desired.


2016 ◽  
Vol 6 (01) ◽  
pp. 5218
Author(s):  
Laxmi Mohandas ◽  
Anju T. R. ◽  
Sarita G. Bhat*

An assortment of redox-active phenazine compounds like pyocyanin with their characteristic blue-green colour are synthesized by Pseudomonas aeruginosa, Gram-negative opportunistic pathogens, which are also considered one of the most commercially valuable microorganisms. In this study, pyocyanin from Pseudomonas aeruginosa BTRY1 from food sample was assessed for its antibiofilm activity by micro titer plate assay against strong biofilm producers belonging to the genera Bacillus, Staphylococcus, Brevibacterium and Micrococcus. Pyocyanin inhibited biofilm activity in very minute concentrations. This was also confirmed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). Both SEM and CLSM helped to visualize the biocontrol of biofilm formation by eight pathogens. The imaging and quantification by CLSM also established the impact of pyocyanin on biofilm-biocontrol mainly in the food industry.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Wei Wang ◽  
Xiaoya Wang

AbstractBackgroundPseudomonas aeruginosa is an opportunistic pathogen which is associated with nosocomial infections and causes various diseases including urinary tract infection, pneumonia, soft-tissue infection and sepsis. The emergence of P. aeruginosa-acquired metallo-β-lactamase (MBL) is most worrisome and poses a serious threat during treatment and infection control. The objective of this study was to identify antibiotic susceptibility, phenotypic detection of MBL production and to determine the prevalence of MBL genes in carbapenem-resistant P. aeruginosa isolated from different clinical samples.MethodsA total of 329 non-duplicate P. aeruginosa isolated from various clinical samples from two hospitals in China between September 2017 and March 2019 were included in this study. Phenotypic detection of MBL was performed by the combined detection method using imipenem and imipenem-ethylenediaminetetraacetic acid (EDTA) discs. MBL-encoding genes including blaVIM-1, blaVIM-2, blaIMP-1, blaIMP-2, blaSPM-1, blaSIM, blaNDM-1 and blaGIM were detected by polymerase chain reaction (PCR).ResultsOf the 329 P. aeruginosa, majority of the isolates were resistant to imipenem (77.5%) followed by meropenem (64.7%). Of the 270 P. aeruginosa isolates tested, 149 (55.2%) isolates were found to be positive for MBL detection. Of the different samples, 57.8% (n = 26) of P. aeruginosa isolated from blood were found to be positive for MBL production. Of the various MBL genes, blaIMP-1 (28.2%) was the most predominant gene detected followed by blaVIM-2 (18.8%), blaVIM-1 (16.1%), blaNDM-1 (9.4%), blaIMP-2 (6.7%), blaSIM (6.0%), blaSPM-1 (4.0%) and blaGIM (1.3%) genes.ConclusionsThe high resistance of P. aeruginosa toward imipenem and meropenem and the high prevalence of blaIMP-1 and blaVIM-2 set the alarm on the increasing, perhaps the increased, carbapenem resistance. In addition to routine antibiotic susceptibility testings, our results emphasize the importance of both the phenotypic and genotypic MBL detection methods in routine practice for early detection of carbapenem resistance and to prevent further dissemination of this resistant pathogen.


Author(s):  
Nisha Patidar ◽  
Nitya Vyas ◽  
Shanoo Sharma ◽  
Babita Sharma

Abstract Objective Carbapenems are last resort antibiotics for multidrug-resistant Enterobacteriaceae. However, resistance to carbapenem is increasing at an alarming rate worldwide leading to major therapeutic failures and increased mortality rate. Early and effective detection of carbapenemase producing carbapenem-resistant Enterobacteriaceae (CRE) is therefore key to control dissemination of carbapenem resistance in nosocomial as well as community-acquired infection. The aim of present study was to evaluate efficacy of Modified strip Carba NP (CNP) test against Modified Hodge test (MHT) for early detection of carbapenemase producing Enterobacteriaceae (CPE). Material and Methods Enterobacteriaceae isolated from various clinical samples were screened for carbapenem resistance. A total of 107 CRE were subjected to MHT and Modified strip CNP test for the detection of CPE. Statistical Analysis It was done on Statistical Package for the Social Sciences (SPSS) software, IBM India; version V26. Nonparametric test chi-square and Z-test were used to analyze the results within a 95% level of confidence. Results Out of 107 CRE, 94 (88%) were phenotypically confirmed as carbapenemase producer by Modified strip CNP test and 46 (43%) were confirmed by Modified Hodge Test (MHT). Thirty-eight (36%) isolates showed carbapenemase production by both MHT and CNP test, 56 isolates (52%) were CNP test positive but MHT negative, eight (7%) isolates were MHT positive but CNP test negative and five (5%) isolates were both MHT and CNP test negative. There is statistically significant difference in efficiency of Modified CNP test and MHT (p < 0.05). Conclusion Modified strip CNP test is simple and inexpensive test which is easy to perform and interpret and gives rapid results in less than 5 minutes. It has high degree of sensitivity and specificity. Modified strip CNP test shows significantly higher detection capacity for carbapenemase producers as compared with MHT.


2014 ◽  
Vol 17 (2) ◽  
pp. 321-329 ◽  
Author(s):  
K. Wolska ◽  
P. Szweda ◽  
K. Lada ◽  
E. Rytel ◽  
K. Gucwa ◽  
...  

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


2021 ◽  
Author(s):  
Swetha Kassety ◽  
Stefan Katharios-Lanwermeyer ◽  
George A. O’Toole ◽  
Carey D. Nadell

Pseudomonas aeruginosa strains PA14 and PAO1 are among the two best characterized model organisms used to study the mechanisms of biofilm formation, while also representing two distinct lineages of P. aeruginosa . Previous work has shown that PA14 and PAO1 use different strategies for surface colonization; they also have different extracellular matrix composition and different propensities to disperse from biofilms back into the planktonic phase surrounding them. We expand on this work here by exploring the consequences of these different biofilm production strategies during direct competition. Using differentially labeled strains and microfluidic culture methods, we show that PAO1 can outcompete PA14 in direct competition during early colonization and subsequent biofilm growth, that they can do so in constant and perturbed environments, and that this advantage is specific to biofilm growth and requires production of the Psl polysaccharide. In contrast, the P. aeruginosa PA14 is better able to invade pre-formed biofilms and is more inclined to remain surface-associated under starvation conditions. These data together suggest that while P. aeruginosa PAO1 and PA14 are both able to effectively colonize surfaces, they do so in different ways that are advantageous under different environmental settings. Importance Recent studies indicate that P. aeruginosa PAO1 and PA14 use distinct strategies to initiate biofilm formation. We investigated whether their respective colonization and matrix secretion strategies impact their ability to compete under different biofilm-forming regimes. Our work shows that these different strategies do indeed impact how these strains fair in direct competition: PAO1 dominates during colonization of a naïve surface, while PA14 is more effective in colonizing a pre-formed biofilm. These data suggest that even for very similar microbes there can be distinct strategies to successfully colonize and persist on surfaces during the biofilm life cycle.


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