Investigation of the association of virulence genes and biofilm production with infection and bacterial colonization processes in multidrug-resistant Acinetobacter spp.

Marine mammals have been described as sentinels of the health of marine ecosystems. Therefore, the aim of this study was to investigate (i) the presence of extended-spectrum β-lactamase (ESBL)- and AmpC-producing Enterobacterales, which comprise several bacterial families important to the healthcare sector, as well as (ii) the presence of Salmonella in these coastal animals. The antimicrobial resistance pheno- and genotypes, as well as biocide susceptibility of Enterobacterales isolated from stranded marine mammals, were determined prior to their rehabilitation. All E. coli isolates (n = 27) were screened for virulence genes via DNA-based microarray, and twelve selected E. coli isolates were analyzed by whole-genome sequencing. Seventy-one percent of the Enterobacterales isolates exhibited a multidrug-resistant (MDR) pheno- and genotype. The gene blaCMY (n = 51) was the predominant β-lactamase gene. In addition, blaTEM-1 (n = 38), blaSHV-33 (n = 8), blaCTX-M-15 (n = 7), blaOXA-1 (n = 7), blaSHV-11 (n = 3), and blaDHA-1 (n = 2) were detected. The most prevalent non-β-lactamase genes were sul2 (n = 38), strA (n = 34), strB (n = 34), and tet(A) (n = 34). Escherichia coli isolates belonging to the pandemic sequence types (STs) ST38, ST167, and ST648 were identified. Among Salmonella isolates (n = 18), S. Havana was the most prevalent serotype. The present study revealed a high prevalence of MDR bacteria and the presence of pandemic high-risk clones, both of which are indicators of anthropogenic antimicrobial pollution, in marine mammals.

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Bacteriophage Cocktail-Mediated Inhibition of Pseudomonas aeruginosa Biofilm on Endotracheal Tube Surface

Antibiotics ◽

10.3390/antibiotics10010078 ◽

2021 ◽

Vol 10 (1) ◽

pp. 78

Author(s):

Viviane C. Oliveira ◽

Ana P. Macedo ◽

Luís D. R. Melo ◽

Sílvio B. Santos ◽

Paula R. S. Hermann ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Endotracheal Tube ◽

Metabolic Activity ◽

Bacterial Colonization ◽

Multidrug Resistant ◽

Scientific Data ◽

Tube Surface ◽

Screening Assay ◽

Biofilm Growth ◽

Phage Cocktail

Although different strategies to control biofilm formation on endotracheal tubes have been proposed, there are scarce scientific data on applying phages for both removing and preventing Pseudomonas aeruginosa biofilms on the device surface. Here, the anti-biofilm capacity of five bacteriophages was evaluated by a high content screening assay. We observed that biofilms were significantly reduced after phage treatment, especially in multidrug-resistant strains. Considering the anti-biofilm screens, two phages were selected as cocktail components, and the cocktail’s ability to prevent colonization of the endotracheal tube surface was tested in a dynamic biofilm model. Phage-coated tubes were challenged with different P. aeruginosa strains. The biofilm growth was monitored from 24 to 168 h by colony forming unit counting, metabolic activity assessment, and biofilm morphology observation. The phage cocktail promoted differences of bacterial colonization; nonetheless, the action was strain dependent. Phage cocktail coating did not promote substantial changes in metabolic activity. Scanning electron microscopy revealed a higher concentration of biofilm cells in control, while tower-like structures could be observed on phage cocktail-coated tubes. These results demonstrate that with the development of new coating strategies, phage therapy has potential in controlling the endotracheal tube-associated biofilm.

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Serotype distribution, antimicrobial susceptibility, antimicrobial resistance genes and virulence genes of Salmonella isolated from a pig slaughterhouse in Yangzhou, China

AMB Express ◽

10.1186/s13568-019-0936-9 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Quan Li ◽

Jian Yin ◽

Zheng Li ◽

Zewei Li ◽

Yuanzhao Du ◽

...

Keyword(s):

Public Health ◽

Antimicrobial Resistance ◽

Resistance Genes ◽

Antimicrobial Susceptibility ◽

Virulence Genes ◽

Multidrug Resistant ◽

Resistance Rate ◽

Economic Losses ◽

Production Chain ◽

Antimicrobial Resistance Genes

AbstractSalmonella is an important food-borne pathogen associated with public health and high economic losses. To investigate the prevalence and the characteristics of Salmonella in a pig slaughterhouse in Yangzhou, a total of 80 Salmonella isolates were isolated from 459 (17.43%) samples in 2016–2017. S. Derby (35/80, 43.75%) was the most prevalent, followed by S. Rissen (16/80, 20.00%) and S. Newlands (11/80, 13.75%). The highest rates of susceptibility were observed to cefoxitin (80/80, 100.0%) and amikacin (80/80, 100.0%), followed by aztreonam (79/80, 98.75%) and nitrofurantoin (79/80, 98.75%). The highest resistance rate was detected for tetracycline (65/80, 81.25%), followed by ampicillin (60/80, 75.00%), bactrim (55/80, 68.75%), and sulfisoxazole (54/80, 67.50%). Overall, 91.25% (73/80) of the isolates were resistant to at least one antibiotic, while 71.25% (57/80) of the isolate strains were multidrug resistant in the antimicrobial susceptibility tested. In addition, 86.36% (19/22) of the 22 antimicrobial resistance genes in the isolates were identified. Our data indicated that the resistance to certain antimicrobials was significantly associated, in part, with antimicrobial resistance genes. Furthermore, 81.25% (65/80) isolates harbored the virulence gene of mogA, of which 2 Salmonella Typhimurium isolates carried the mogA, spvB and spvC virulence genes at the same time. The results showed that swine products in the slaughterhouse were contaminated with multidrug resistant Salmonella commonly, especially some isolates carry the spv virulence genes. The virulence genes might facilitate the dissemination of the resistance genes to consumers along the production chain, suggesting the importance of controlling Salmonella during slaughter for public health.

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Virulence Genes of the Phytopathogen Rhodococcus fascians Show Specific Spatial and Temporal Expression Patterns During Plant Infection

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2002.15.4.398 ◽

2002 ◽

Vol 15 (4) ◽

pp. 398-403 ◽

Cited By ~ 12

Author(s):

Karen Cornelis ◽

Tania Maes ◽

Mondher Jaziri ◽

Marcelle Holsters ◽

Koen Goethals

Keyword(s):

Virulence Genes ◽

Expression Profiles ◽

Bacterial Colonization ◽

Expression Patterns ◽

Shoot Meristem ◽

Plant Surface ◽

Phytopathogenic Bacterium ◽

Plant Parts ◽

Plant Infection ◽

Rhodococcus Fascians

The phytopathogenic bacterium Rhodococcus fascians provokes shoot meristem formation and malformations on aerial plant parts, mainly at the axils. The interaction is accompanied by bacterial colonization of the plant surface and tissues. Upon infection, the two bacterial loci required for full virulence, fas and att, were expressed only at the sites of symptom development, although their expression profiles differed both spatially and temporally. The att locus was expressed principally in bacteria located on the plant surface at early stages of infection. Expression of the fas locus occurred throughout infection, mainly in bacteria that were penetrating, or had penetrated, the plant tissues and coincided with sites of meristem initiation and proliferation. The implications for the regulation of virulence genes of R. fascians during plant infection are discussed.

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Acinetobacter species in laboratory mice: species survey and antimicrobial resistance

Laboratory Animals ◽

10.1177/0023677218818598 ◽

2018 ◽

Vol 53 (5) ◽

pp. 470-477

Author(s):

Laurentiu Benga ◽

Andrea T. Feßler ◽

W. Peter M. Benten ◽

Eva Engelhardt ◽

Karl Köhrer ◽

...

Keyword(s):

Antimicrobial Agents ◽

Inhibitory Concentration ◽

Rpob Gene ◽

Multidrug Resistant ◽

Laboratory Mice ◽

Hospital Epidemiology ◽

Acinetobacter Species ◽

Acinetobacter Spp ◽

Susceptibility Profiles ◽

Very High

The extra-hospital epidemiology of Acinetobacter infections is a subject of debate. In recent years, the prevalence of animal multidrug-resistant Acinetobacter infections has increased considerably. The goal of the present study was to specify Acinetobacter species isolated from laboratory mice and to test them for their antimicrobial susceptibility. During routine microbiological monitoring of laboratory mice, 12 Acinetobacter spp. were isolated. By means of 16S rRNA and rpoB gene sequencing, seven of the isolates were identified as Acinetobacter radioresistens, three isolates belonged to Acinetobacter genomospecies 14BJ, one isolate was classified as Acinetobacter pitii and one as Acinetobacter sp. ANC 4051. The distribution of the minimal inhibitory concentration (MIC) values was uniform for 21 of the 23 antimicrobial agents tested, whereas a broad MIC distribution was recorded for tulathromycin and streptomycin. The MIC values recorded were low for the majority of the antibiotics tested. Nevertheless, very high MIC values, which will probably render a therapeutic approach using these substances unsuccessful, were recorded for florfenicol, tiamulin, tilmicosin and cephalothin in most of the isolates. In conclusion, we document colonization of laboratory mice with different Acinetobacter species, displaying similar antibiotic susceptibility profiles, with possible implications in the Acinetobacter epidemiology as well as in the husbandry and experimentation of the colonized animals.

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Antibiotic Resistance and Biofilm Production in Catalase-Positive Gram-Positive Cocci Isolated from Brazilian Pasteurized Milk

Journal of Food Quality and Hazards Control ◽

10.18502/jfqhc.7.2.2886 ◽

2020 ◽

Cited By ~ 1

Author(s):

M.A.A. Machado ◽

W.A. Ribeiro ◽

V.S. Toledo ◽

G.L.P.A. Ramos ◽

H.C. Vigoder ◽

...

Keyword(s):

Antibiotic Resistance ◽

Qualitative Evaluation ◽

Multidrug Resistant ◽

Gram Positive ◽

Antibiotic Resistant ◽

Pasteurized Milk ◽

Biofilm Production ◽

Diffusion Technique ◽

Gram Positive Cocci

Background: Milk is a reservoir for several groups of microorganisms, which may pose health risks. The aim of this work was to assess the antibiotic resistance and biofilm production in catalase-positive Gram-positive cocci isolated from Brazilian pasteurized milk. Methods: The bacteria were isolated using Baird-Parker agar and identified by MatrixAssisted Laser Desorption/Ionization-Time-Of-Flight (MALDI-TOF) mass spectrometer. Disk diffusion technique was used to evaluate antimicrobial susceptibility. For qualitative evaluation of biofilm production, the growth technique was used on Congo Red Agar. Results: Totally, 33 out of 64 isolates were identified, including Staphylococcus epidermidis (n=3; 4.7%), Macrococcus caseolyticus (n=14; 21.9%), and Kocuria varians (n=16; 25%). Twenty-two isolates were resistant to at least one antibiotic. Biofilm production was detected in only 5 isolates of K. varians and 1 isolate of S. epidermidis. All 14 M. caseolyticus isolates were resistant to at least one antibiotic; but, multidrug resistant (MDR) isolates were not detected. Among all K. varians isolates, 4 were resistant to at least one antibiotic from three different classes and were considered to be MDR. Conclusion: The presence of antibiotic-resistant M. caseolyticus, S. epidermidis, and K. varians isolates, especially MDRs, in milk samples highlights the possible role of milk as a reservoir of resistance genes

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Association among biofilm formation, virulence gene expression, and antibiotic resistance in Proteus mirabilis isolates from diarrhetic animals in northeast China

10.21203/rs.2.16502/v2 ◽

2020 ◽

Author(s):

Yadong Sun ◽

Shanshan Wen ◽

Lili Zhao ◽

Qiqi Xia ◽

Yue Pan ◽

...

Keyword(s):

Gene Expression ◽

Antibiotic Resistance ◽

Biofilm Formation ◽

Northeast China ◽

Virulence Gene ◽

Drug Susceptibility ◽

Multidrug Resistant ◽

Virulence Gene Expression ◽

Biofilm Production ◽

High Level

Abstract Background The aim of this study was to investigate the association among biofilm formation, virulence gene expression, and antibiotic resistance in P. mirabilis isolates collected from diarrhetic animals (n = 176) in northeast China between September 2014 and October 2016. Results Approximately 92.05% of the isolates were biofilm producers, whereas 7.95% of the isolates were non-producers. The prevalence of virulence genes in biofilm producers was significantly higher than that in non-producers. Biofilm production was significantly associated with the expression of ureC , zapA , rsmA , hmpA , mrpA , atfA , and pmfA ( P < 0.05). Drug susceptibility tests revealed that approximately 76.7% of the isolates were multidrug-resistant (MDR) and extensively drug-resistant (XDR). Biofilm production was significantly associated with resistance to doxycycline, tetracycline, sulfamethoxazole, kanamycin, and cephalothin ( P < 0.05). Although the pathogenicity of the biofilm producers was stronger than that of the non-producers, the biofilm-forming ability of the isolates was not significantly associated with morbidity and mortality in mice ( P > 0.05). Conclusion Our findings suggested that a high level of multidrug resistance in diarrhetic animals infected with P. mirabilis in northeast China.The results of this study indicated that the positive rates of the genes expressed by biofilm-producing P. mirabilis isolates were significantly higher than those expressed by non-producing isolates.

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IN INTRA-ABDOMINAL INFECTIONS AND PERITONITIS

Kharkiv Surgical School ◽

10.37699/2308-7005.2.2021.17 ◽

2021 ◽

pp. 90-96

Author(s):

A. V. Kotov ◽

V. I. Desyaterik ◽

S. P. Mikhno

Keyword(s):

Absolute Number ◽

Multidrug Resistant ◽

E Coli ◽

The Past ◽

Rational Therapy ◽

Acinetobacter Spp ◽

The Difference ◽

Abdominal Infections ◽

Staphylococcus Spp ◽

Klebsiella Spp

Summary. Purpose of the reserche. To study changes in microflora and sensitivity of isolated strains to antibiotics using bacteriological research methods for intra-abdominal infections and peritonitis to determine their resistance when planning antibiotic therapy. Results and discussion. The paper presents data from a retrospective analysis of the results of studies of microflora and its resistance in intra-abdominal infections (IAI) and peritonitis for 2 periods: I period — from january 2007 to december 2008, II period — from january 2018 to december 2019. The difference between period II and I was in the increase in the number of individual pathogenic strains of microorganisms. Thus, the number of Klebsiella spp. increased from 13.8 % to 23.8 %, which in absolute number of their total number amounted to a 73.5 %, ranking second in the overall structure among pathogens sown in IAI and peritonitis. The number of strains of Staphylococcus spp., Enterobacter spp., Acinetobacter spp. has also increased by 2.4–5.8 % respectively. Among the strains Klebsiella spp., E. coli and Staphylococcus spp. the number of poly- and multi-polyresistant forms has increased. Thus, the number of such forms among Klebsiella spp. increased from 19.2 to 44.5 %, Staphylococcus spp. — from 43.8 to 67.1 % and E. coli from 18.2 to 23.5 %, respectively. Conclusions. Over the past 10 years, with IAI and peritonitis, the most significant changes were revealed on the part of pathogenic strains of Klebsiella spp., Staphylococcus spp. and Acinetobacter spp. Multidrug resistant strains were predominantly susceptible to carbapenems, semisynthetic ureidopenicillins, aminoglycosides, glycopeptides, oxazalidinones, phosphonoic acid derivatives. In the context of changes in the microbial landscape observed over the past decade, an increase in the number of poly- and multi-resistant forms of pathogenic microorganisms in IAI and peritonitis, the choice of antibiotics for rational therapy should be based solely on bacterioscopy and antibiograms.

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Occurrence of virulent multidrug-resistantEnterococcus faecalisandEnterococcus faeciumin the pigs, farmers and farm environments in Malaysia

PeerJ ◽

10.7717/peerj.5353 ◽

2018 ◽

Vol 6 ◽

pp. e5353 ◽

Cited By ~ 6

Author(s):

Shiang Chiet Tan ◽

Chun Wie Chong ◽

Cindy Shuan Ju Teh ◽

Peck Toung Ooi ◽

Kwai Lin Thong

Keyword(s):

Polymerase Chain Reaction ◽

Antibiotic Resistance ◽

Environmental Factors ◽

Environmental Samples ◽

Virulence Genes ◽

Multidrug Resistant ◽

Peninsular Malaysia ◽

Chain Reaction ◽

Swine Farms ◽

Polymerase Chain

BackgroundEnterococcus faecalisandEnterococcus faeciumare ubiquitous opportunistic pathogens found in the guts of humans and farmed animals. This study aimed to determine the occurrence, antimicrobial resistance, virulence, biofilm-forming ability and genotypes ofE. faecalisandE. faeciumfrom swine farms. Correlations between the genotypes, virulotypes, antibiotic resistance, and the environmental factors such as locality of farms and farm hygiene practice were explored.MethodsE. faecalisandE. faeciumstrains were isolated from the oral, rectal and fecal samples of 140 pigs; nasal, urine and fecal samples of 34 farmers working in the farms and 42 environmental samples collected from seven swine farms located in Peninsular Malaysia. Antibiotic susceptibility test was performed using the disk diffusion method, and the antibiotic resistance and virulence genes were detected by Polymerase Chain Reaction. Repetitive Extragenic Palindromic-Polymerase Chain Reaction and Pulsed-Field Gel Electrophoresis were performed to determine the clonality of the strains. Crosstab/Chi-square test and DistLM statistical analyses methods were used to determine the correlations between the genotypes, virulence factors, antibiotic resistance, and the environmental factors.ResultsA total of 211E. faecalisand 42E. faeciumwere recovered from 140 pigs, 34 farmers and 42 environmental samples collected from seven swine farms in Peninsular Malaysia. Ninety-eight percent of the strains were multidrug-resistant (resistant to chloramphenicol, tetracycline, ciprofloxacin and erythromycin). Fifty-two percent of the strains formed biofilms. Virulence genesefa, asaI, gelE,esp,cylandacegenes were detected. Virulence genesefaandasaI were most prevalent inE. faecalis(90%) andE. faecium(43%), respectively. Cluster analyses based on REP-PCR and PFGE showed the strains were genetically diverse. Overall, the strains isolated from pigs and farmers were distinct, except for three highly similar strains found in pigs and farmers. The strains were regional- and host-specific.DiscussionThis study revealed alarming high frequencies of multidrug-resistant enterococci in pigs and swine farmers. The presence of resistance and virulence genes and the ability to form biofilm further enhance the persistence and pathogenicity of the strains. Although the overall clonality of the strains were regionals and host-specific, strains with high similarity were found in different hosts. This study reiterates a need of a more stringent regulation to ensure the proper use of antibiotics in swine husbandry to reduce the wide spread of multidrug-resistant strains.

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