scholarly journals Detection of harmful foodborne pathogens in food samples at the points of sale by MALDT-TOF MS in Egypt

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Dalia F. Khater ◽  
Radwa A. Lela ◽  
Mohamed El-Diasty ◽  
Shawky A. Moustafa ◽  
Gamal Wareth
Keyword(s):  
Foodborne Pathogens ◽  
Bacterial Species ◽  
Food Samples ◽  
Human Pathogens ◽  
Point Of Sale ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Maldi Tof ◽  
Staphylococcus Hominis ◽  
Tof Ms

Abstract Objectives Microbes can contaminate foodstuffs resulting in foodborne illnesses. Investigating microbial hazards in foods at the point of sale with rapid tools is required to avoid foodborne illness outbreaks. The current study aimed to identify the microbial hazards in food samples collected from retail shops at sale points using MALDI-TOF MS. Results Food samples were collected from stores and supermarkets in four Delta cities (Tanta, Kutour, Kafr-Elzayat and Benha). Analysis of 178 samples of fish, meat and dairy products revealed 20 different bacterial species. 44.76% of isolates were identified as E. coli, 17.44% were identified as Enterobacter spp., and E. cloacae was predominant. 12.2% were identified as Citrobacter spp., and C. braakii was predominant, and 8.7% were identified as Klebsiella spp., and K. pneumoniae was predominant. Moreover, eight Proteus mirabilis, six Morganella morganii, five Staphylococcus hominis, three Serratia marcescens, two Pseudomonas aeruginosa, one Salmonella typhimurium and one Enterococcus faecalis were detected. Foodstuffs not only be contaminated during production and processing but also during storage and transport. Identification of harmful human pathogens in foodstuffs is alarming and consider threatening to public health. Identification of microbiological hazards in foods using MALDI-TOF MS provides an efficient tool for identifying foodborne pathogens.

Investigation of High-Risk ST131 Clone in Extended Spectrum β-Lactamase–Producing Escherichia coli Isolates in Children

2021 ◽  
Author(s):  
Mehmet E. Bulut ◽  
Gülen Hürkal ◽  
Nazan Dalgıç
Keyword(s):  
Escherichia Coli ◽  
High Risk ◽  
Pediatric Patients ◽  
Pediatric Population ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Maldi Tof ◽  
Extended Spectrum ◽  
St131 Clone ◽  
Tof Ms

Abstract Objective Antimicrobial resistance poses a serious threat to children's health. In recent years, high-risk Escherichia coli ST131 has become an important target for global surveillance studies. The E.coli ST131 clone is associated with extended spectrum β-lactamase (ESBL) production, as well as multidrug resistance and treatment failure. Studies on this clone in the pediatric age group are limited. We aim to investigate the rate of high-risk E. coli ST131 clone in ESBL-positive E. coli isolates obtained from pediatric patients. Methods A total of 292 ESBL-positive E. coli isolates from clinical samples of pediatric patients was included in the study. MALDI-TOF MS system was used for bacterial identification. Susceptibility tests were performed using BD Phoenix automated system. ST131 detection was done by MALDI-TOF-MS. Fisher's exact test was used to compare the groups (significance <0.05). Results A total of 292 isolates was analyzed. The high-risk ST131 clone was detected in 117 (40%) of the 292 ESBL-positive isolates. ST131 rates were found to be significantly higher in children under the age of 5 years compared with children over the age of 5 years (49.3 vs. 31.1%, p = 0.0019). Ciprofloxacin resistance was higher in ST131 isolates (45.6 vs. 31.7%; p < 0.05). Conclusion The rate of the ST131 clone was found to be high in the pediatric population. The significantly high rate of resistance to ciprofloxacin, which is not commonly used in the pediatric population, in ST131 isolates reveals the importance of the spread of high-risk clones for the development of resistance.

scholarly journals MALDI-TOF Mass Spectrometry and Specific Biomarkers: Potential New Key for Swift Identification of Antimicrobial Resistance in Foodborne Pathogens

2019 ◽  
Vol 7 (12) ◽  
pp. 593 ◽  
Author(s):  
Maureen Feucherolles ◽  
Henry-Michel Cauchie ◽  
Christian Penny
Keyword(s):  
Mass Spectrometry ◽  
Antimicrobial Resistance ◽  
Foodborne Pathogens ◽  
Reference Method ◽  
Multi Drug Resistance ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
The Future ◽  
Tof Ms

Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is today the reference method for direct identification of microorganisms in diagnostic laboratories, as it is notably time- and cost-efficient. In the context of increasing cases of enteric diseases with emerging multi-drug resistance patterns, there is an urgent need to adopt an efficient workflow to characterize antimicrobial resistance (AMR). Current approaches, such as antibiograms, are time-consuming and directly impact the “patient-physician” workflow. Through this mini-review, we summarize how the detection of specific patterns by MALDI-TOF MS, as well as bioinformatics, become more and more essential in research, and how these approaches will help diagnostics in the future. Along the same lines, the idea to export more precise biomarker identification steps by MALDI-TOF(/TOF) MS data towards AMR identification pipelines is discussed. The study also critically points out that there is currently still a lack of research data and knowledge on different foodborne pathogens as well as several antibiotics families such as macrolides and quinolones, and many questions are still remaining. Finally, the innovative combination of whole-genome sequencing and MALDI-TOF MS could be soon the future for diagnosis of antimicrobial resistance in foodborne pathogens.

scholarly journals Determination of Drug Efflux Pump Efficiency in Drug-Resistant Bacteria Using MALDI-TOF MS

Antibiotics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 639 ◽  
Author(s):  
Wen-Jung Lu ◽  
Hsuan-Ju Lin ◽  
Pang-Hung Hsu ◽  
Hong-Ting Victor Lin
Keyword(s):  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Resistant Bacteria ◽  
Pump Efficiency ◽  
Drug Efflux ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Maldi Tof ◽  
Conventional Methods ◽  
Tof Ms

Multidrug efflux pumps play an essential role in antibiotic resistance. The conventional methods, including minimum inhibitory concentration and fluorescent assays, to monitor transporter efflux activity might have some drawbacks, such as indirect evidence or interference from color molecules. In this study, MALDI-TOF MS use was explored for monitoring drug efflux by a multidrug transporter, and the results were compared for validation with the data from conventional methods. Minimum inhibitory concentration was used first to evaluate the activity of Escherichia coli drug transporter AcrB, and this analysis showed that the E. coli overexpressing AcrB exhibited elevated resistance to various antibiotics and dyes. Fluorescence-based studies indicated that AcrB in E. coli could decrease the accumulation of intracellular dyes and display various efflux rate constants for different dyes, suggesting AcrB’s efflux activity. The MALDI-TOF MS analysis parameters were optimized to maintain a detection accuracy for AcrB’s substrates; furthermore, the MS data showed that E. coli overexpressing AcrB led to increased ions abundancy of various dyes and drugs in the extracellular space at different rates over time, illustrating continuous substrate efflux by AcrB. This study concluded that MALDI-TOF MS is a reliable method that can rapidly determine the drug pump efflux activity for various substrates.

scholarly journals Detection of Carbapenemase-Producing Enterobacteriaceae in the Baltic Countries and St. Petersburg Area

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Anastasia Pavelkovich ◽  
Arta Balode ◽  
Petra Edquist ◽  
Svetlana Egorova ◽  
Marina Ivanova ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Cost Effective ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Maldi Tof ◽  
Baltic Countries ◽  
Exact Data ◽  
Cost Effective Method ◽  
The Baltic ◽  
Tof Ms

The spread of carbapenemase-producing Enterobacteriaceae is a global problem; however, no exact data on the epidemiology of carbapenemase in the Baltic countries and St. Petersburg area is available. We aimed to evaluate the epidemiology of carbapenemase-producingEscherichia coliandKlebsiella pneumoniaein the Baltic States and St. Petersburg, Russia, and to compare the different methods for carbapenemase detection. From January to May 2012, allK. pneumoniae  n=1983andE. coli  n=7774clinical isolates from 20 institutions in Estonia, Latvia, Lithuania, and St. Petersburg, Russia were screened for carbapenem susceptibility. The IMP, VIM, GIM, NDM, KPC, and OXA-48 genes were detected using real-time PCR and the ability to hydrolyze ertapenem was determined using MALDI-TOF MS. Seventy-seven strains were found to be carbapenem nonsusceptible. From these, 15K. pneumoniaestrains hydrolyzed ertapenem and carried theblaNDMgene. All of these strains carried integron 1 and most carried integron 3 as well as genes of the CTX-M-1 group. No carbapenemase-producingE. coliorK. pneumoniaestrains were found in Estonia, Latvia, or Lithuania; however, NDM-positiveK. pneumoniaewas present in the hospital in St. Petersburg, Russia. A MALDI-TOF MS-based assay is a suitable and cost-effective method for the initial confirmation of carbapenemase production.

scholarly journals Rapid identification of Legionella species by mass spectrometry

2010 ◽  
Vol 59 (3) ◽  
pp. 273-284 ◽  
Author(s):  
Claire Moliner ◽  
Christophe Ginevra ◽  
Sophie Jarraud ◽  
Christophe Flaudrops ◽  
Marielle Bedotto ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Bacterial Species ◽  
Rapid Identification ◽  
Species Level ◽  
Blind Test ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tract Infections ◽  
Pcr Targeting ◽  
Tof Ms

Legionella species are facultative, intracellular bacteria that infect macrophages and protozoa, with the latter acting as transmission vectors to humans. These fastidious bacteria mostly cause pulmonary tract infections and are routinely identified by various molecular methods, mainly PCR targeting the mip gene and sequencing, which are expensive and time-consuming. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has emerged as a rapid and inexpensive method for identification of bacterial species. This study evaluated the use of MALDI-TOF-MS for rapid species and serogroup identification of 21 Legionella species recognized as human pathogens. To this end, a reference MS database was developed including 59 Legionella type strains, and a blind test was performed using 237 strains from various species. Two hundred and twenty-three of the 237 strains (94.1 %) were correctly identified at the species level, although ten (4.2 %) were identified with a score lower than 2.0. Fourteen strains (5.9 %) from eight species were misidentified at the species level, including seven (3.0 %) with a significant score, suggesting an intraspecific variability of protein profiles within some species. MALDI-TOF-MS was reproducible but could not identify Legionella strains at the serogroup level. When compared with mip gene sequencing, MALDI-TOF-MS exhibited a sensitivity of 99.2 and 89.9 % for the identification of Legionella strains at the genus and species level, respectively. This study demonstrated that MALDI-TOF-MS is a reliable tool for the rapid identification of Legionella strains at the species level.

scholarly journals Usefulness of the MALDI-TOF MS technology with membrane filter protocol for the rapid identification of microorganisms in perioperative drainage fluids of hepatobiliary pancreatic surgery

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246002
Author(s):  
Kazuyuki Sogawa ◽  
Shigetsugu Takano ◽  
Takayuki Ishige ◽  
Hideyuki Yoshitomi ◽  
Shingo Kagawa ◽  
...  
Keyword(s):  
Membrane Filtration ◽  
High Reliability ◽  
Membrane Filter ◽  
Perioperative Complications ◽  
Bacterial Species ◽  
Bacterial Identification ◽  
Maldi Tof Ms ◽  
Drainage Fluid ◽  
Maldi Tof ◽  
Tof Ms

Surgical site infections (SSIs) are significant and frequent perioperative complications, occurring due to the contamination of the surgical site. The late detection of SSIs, especially organ/space SSIs which are the more difficult to treat, often leads to severe complications. An effective method that can identify bacteria with a high accuracy, leading to the early detection of organ/space SSIs, is needed. Ninety-eight drainage fluid samples obtained from 22 patients with hepatobiliary pancreatic disease were analyzed to identify microorganisms using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) with a new membrane filtration protocol and rapid BACpro® pretreatment compared to sole rapid BACpro® pretreatment. The levels of detail of rapid BACpro® pretreatment with or without filtration were also evaluated for the accuracy of bacterial identification. We found that reliable scores for E. coli and E. faecalis were obtained by inoculation with 1.0 × 104 CFU/ml after preparation of the membrane filter with rapid BACpro®, indicating approximately 10-folds more sensitive compared to sole rapid BACpro® pretreatment in drainage fluid specimens. Among 60 bacterial positive colonies in drainage fluid specimens, the MALDI-TOF MS and the membrane filtration with rapid BACpro® identified 53 isolates (88.3%) with a significantly higher accuracy, compared to 25 isolates in the rapid BACpro® pretreatment group (41.7%) (p < 0.001). Among the 78 strains, 14 enteric Gram-negative bacteria (93.0%) and 55 Gram-positive cocci (87.3%) were correctly identified by the membrane filtration with rapid BACpro® with a high reliability. This novel protocol could identify bacterial species within 30 min, at $2-$3 per sample, thus leading to cost and time savings. MALDI-TOF MS with membrane filter and rapid BACpro® is a quick and reliable method for bacterial identification in drainage fluids. The shortened analysis time will enable earlier selection of suitable antibiotics for treatment of organ/space SSIs to improve patients’ outcomes.

scholarly journals Mass Spectrometry Proteotyping-Based Detection and Identification of Staphylococcus aureus, Escherichia coli, and Candida albicans in Blood

2021 ◽  
Vol 11 ◽  
Author(s):  
Nahid Kondori ◽  
Amra Kurtovic ◽  
Beatriz Piñeiro-Iglesias ◽  
Francisco Salvà-Serra ◽  
Daniel Jaén-Luchoro ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Blood Cultures ◽  
Blood Samples ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Maldi Tof ◽  
Detection And Identification ◽  
Tof Ms

Bloodstream infections (BSIs), the presence of microorganisms in blood, are potentially serious conditions that can quickly develop into sepsis and life-threatening situations. When assessing proper treatment, rapid diagnosis is the key; besides clinical judgement performed by attending physicians, supporting microbiological tests typically are performed, often requiring microbial isolation and culturing steps, which increases the time required for confirming positive cases of BSI. The additional waiting time forces physicians to prescribe broad-spectrum antibiotics and empirically based treatments, before determining the precise cause of the disease. Thus, alternative and more rapid cultivation-independent methods are needed to improve clinical diagnostics, supporting prompt and accurate treatment and reducing the development of antibiotic resistance. In this study, a culture-independent workflow for pathogen detection and identification in blood samples was developed, using peptide biomarkers and applying bottom-up proteomics analyses, i.e., so-called “proteotyping”. To demonstrate the feasibility of detection of blood infectious pathogens, using proteotyping, Escherichia coli and Staphylococcus aureus were included in the study, as the most prominent bacterial causes of bacteremia and sepsis, as well as Candida albicans, one of the most prominent causes of fungemia. Model systems including spiked negative blood samples, as well as positive blood cultures, without further culturing steps, were investigated. Furthermore, an experiment designed to determine the incubation time needed for correct identification of the infectious pathogens in blood cultures was performed. The results for the spiked negative blood samples showed that proteotyping was 100- to 1,000-fold more sensitive, in comparison with the MALDI-TOF MS-based approach. Furthermore, in the analyses of ten positive blood cultures each of E. coli and S. aureus, both the MALDI-TOF MS-based and proteotyping approaches were successful in the identification of E. coli, although only proteotyping could identify S. aureus correctly in all samples. Compared with the MALDI-TOF MS-based approaches, shotgun proteotyping demonstrated higher sensitivity and accuracy, and required significantly shorter incubation time before detection and identification of the correct pathogen could be accomplished.

scholarly journals Analysis of the Degradation of Broad-Spectrum Cephalosporins by OXA-48-Producing Enterobacteriaceae Using MALDI-TOF MS

2019 ◽  
Vol 7 (12) ◽  
pp. 614
Author(s):  
Marina Oviaño ◽  
María Rosario Rodicio ◽  
Jürgen J. Heinisch ◽  
Rosaura Rodicio ◽  
Germán Bou ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Negative Control ◽  
Point Of View ◽  
Reaction Products ◽  
Beta Lactam ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Maldi Tof ◽  
Lactam Ring ◽  
Tof Ms

The objective of the study was to evaluate the activity of OXA-48 against different broad-spectrum cephalosporins and to identify the reaction products by MALDI-TOF MS. The action of OXA-48 on cefotaxime, ceftazidime, and ceftriaxone was assessed by this method, using an Escherichia coli J53 transconjugant carrying only the ~62 Kb IncL plasmid containing the blaOXA-48 gene, and the same strain without any plasmid was included as a negative control. In addition, a collection of 17 clinical OXA-48-producing Enterobacteriaceae, which were susceptible to broad-spectrum cephalosporins, was evaluated. MALDI-TOF MS-based analysis of the E. coli transconjugant carrying the blaOXA-48-harboring plasmid, and also the clinical isolates, showed degradation of cefotaxime into two inactive compounds—decarboxylated and deacetylated cefotaxime (~370 Da) and deacetyl cefotaxime (~414 Da), both with the hydrolyzed beta-lactam ring. Reaction products were not obtained when the experiment was performed with ceftriaxone or ceftazidime. From a clinical point of view, our study supports the idea that the efficacy of cefotaxime against OXA-48-producing Enterobacteriaceae is doubtful, in contrast to ceftazidime and ceftriaxone which could be valid choices for treating infections caused by these bacteria. However, further clinical studies confirming this hypothesis are required.

Comparative Proteomics of Commensal and Pathogenic Strains of Escherichia coli

2020 ◽  
Vol 27 (11) ◽  
pp. 1171-1177
Author(s):  
Neelja Singhal ◽  
Divakar Sharma ◽  
Manish Kumar ◽  
Deepa Bisht ◽  
Jugsharan Singh Virdi
Keyword(s):  
Escherichia Coli ◽  
Proteomic Analysis ◽  
Two Dimensional Gel Electrophoresis ◽  
Maldi Tof Ms ◽  
E Coli ◽  
Comparative Proteomic Analysis ◽  
Maldi Tof ◽  
Northern India ◽  
Flight Mass Spectrometry ◽  
Tof Ms

Background: Most of the proteomic studies in Escherichia coli have focussed on pathogenic strains, while very few studies have studied the commensal strains. It is important to study the commensal strains because under the selective pressure of their habitat, commensal strains might serve as reservoirs of virulent and pathogenic strains. Objective: In this study, we have performed a comparative proteomic analysis of commensal and pathogenic strains of E. coli isolated from a major river flowing through northern India. Methods: Proteins were resolved by two dimensional gel electrophoresis and the differentially expressed proteins were identified using matrix-assisted laser desorption ionization-time of flight mass-spectrometry (MALDI-TOF MS). Results: Many proteins of the commensal strain showed an increased expression compared to the pathogenic strain, of which seventeen proteins were identified by MALDI-TOF MS. Functional classification of these proteins revealed that they belonged to different functional pathways like energy metabolism, nucleotide and nucleoside conversions, translation, biosynthesis of amino acids and motility and energytaxis/chemotaxis. Conclusion: As per the best of our knowledge, this is the first report on comparative proteomic analysis of E. coli commensal and pathogenic strains of aquatic origin. Our results suggest that the increased production of these proteins might play an important role in adaptation of E. coli to a commensal/pathogenic lifestyle. However, further experiments are required to understand the precise role of these proteins in regulating the pathogenicity/commensalism of E. coli.

scholarly journals Rapid and cost-effective identification of Bartonella species using mass spectrometry

2009 ◽  
Vol 58 (9) ◽  
pp. 1154-1159 ◽  
Author(s):  
Pierre-Edouard Fournier ◽  
Carine Couderc ◽  
Sylvain Buffet ◽  
Christophe Flaudrops ◽  
Didier Raoult
Keyword(s):  
Mass Spectrometry ◽  
Species Identification ◽  
Chemical Reactivity ◽  
Bacterial Species ◽  
Cost Effective ◽  
Molecular Techniques ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Tof Ms

Bacteria of the genus Bartonella are emerging zoonotic bacteria recognized in a variety of human diseases. Due to their poor chemical reactivity, these fastidious bacteria are poorly characterized using routine phenotypic laboratory tests. Identification is usually achieved using molecular techniques that are time-consuming, expensive and technically demanding. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as a new technique for bacterial species identification. This study evaluated the use of MALDI-TOF MS for rapid genus and species identification of Bartonella species. Reference strains representing 17 recognized Bartonella species were studied. For each species, MS spectra for four colonies were analysed. The consensus spectrum obtained for each species was unique among spectra obtained for 2843 bacteria within the Bruker database, including 109 alphaproteobacteria. Thirty-nine additional blind-coded Bartonella strains were correctly identified at the species level, including 36 with a significant score. Altogether, these data demonstrate that MS is an accurate and reproducible tool for rapid and inexpensive identification of Bartonella species.

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