Enterobacteriaceae Bacteria Research Articles

DETECTION OF CARBAPENEMASE PRODUCING ENTEROBACTERALES AMONG THE CLINICAL ISOLATES OF DIARRHOEAGENIC ESCHERICHIA COLI CAUSING ACUTE GASTROENTERITIS IN CHILDREN BELOW 2 YEARS IN TERTIARY CARE HOSPITAL OF NORTH EAST INDIA

Introduction: Enterobacterales that test resistant to at least one of the carbapenem antibiotics (ertapenem, meropenem, doripenem, or imipenem) are called Carbapenem resistant Enterobacterales (CRE) and if they produce a carbapenemase (an enzyme that can make them resistant to carbapenem antibiotics) they are called Carpenemase producing Enterobacterales (CPE). Children with CRE strains in fecal samples are considered as a high risk group by World Health Organization (WHO), which can spread CRE by intimate contact and travel. This cross-sectional study was conducted in the Department of Microbiology, RIMS, Imphal, Manipur, India fromMethods: Jan 2020 to Feb 2022. A total of 157 children under 2 years of age whose stool culture was positive for diarrhoeagenic Escherichia coli were included in the study. The modied carbapenem inactivation method (mCIM) has been done for detection of carbapenemase producers and the addition of EDTA in eCIM to further differentiate between serine and metallo-β-lactamase producers. Out of 157Result and Discussion: Diarrhoegenic E.coli (DEC) ,Carbapenem resistance was seen in 9 isolates i.e 5.7 %. Out of these 9 isolates, 3 were MBL producers tested by the phenotypic test mCIM and eCIM. All the three MBL producers carried bla NDM-1 gene. mCIM/eCIM assay is designed to simultaneously detect and distinguish the different types of carbapenemases. Carbapenemase genes are often located on plasmids that can be exchanged between Enterobacteriaceae and other Gram-negative bacteria. Carbapenem-resistant K. pneumoniae are currently more frequent and more likely to cause healthcareassociated outbreaks, carbapenem-resistant E. coli pose a greater risk for spread in the community. Conclusion: Screening for carbapenemase producer using mCIM and eCIM essay is important along with infection control measure such as active surveillance through rectal screening for CRE carriage on hospital admission, contact precautions, hand hygiene, patient isolation, environmental sanitation, case notication/agging, antibiotic restriction.

Occurrence of Enterobacteriaceae in medicinal plants sold in local markets of Savar, Dhaka

Medicinal plants can be contaminated with a large diversity of potentially pathogenic bacteria. Ten medicinal plant samples Plantago psyllium, Terminalia bellirica, Terminalia chebula, Phyllanthus emblica, Ocimum basilicum, Glycyrrhiza glabra, Withania somnifera, Andrographis panicula, Bombax ceiba were collected from Amin Bazar and Savar of Savar area to study the presence and abundance of Enterobacteriaceae family bacteria in the herbal plant samples. A total of fifty five (55) bacterial isolates have been isolated from different medicinal plant samples using spread plate method on nutrient Agar media. Culture of bacterial isolate on a number of selective and differential media and biochemical tests (Catalase activity, hemolytic property, fermentation test, Starch hydrolysis, VP test, MR test, MIU test, Indole and casein test etc.) revealed the presence of different Enterobacteriaceae family bacteria in the plant samples. Out of 55 isolates 6 isolates were Salmonella sp. (11%), 2 isolates were Klebsiella sp. (3.63%) and 2 isolates were Enterobacter sp. (3.63%). Antibiotic sensitivity test of bacterial isolates showed that all the identified Enterobacteriaceae family bacteria were sensitive to Kanamycin but resistant to Amoxycilin, Aztreonam and Penicillin-G. Therefore, this study highlighted the necessity for constant quality assessment of herbal medicines to facilitate and ensure safe production and supply of medicinal products suitable for human consumption.
 Jahangirnagar University J. Biol. Sci. 10(1 & 2): 1-8, 2021 (June & December)

Review of Known and Unknown Facts of Klebsiella Pneumoniae and its Relationship with Antibiotics

Antibiotics are commonly used to treat bacterial respiratory infections, but they can exacerbate inflammation by releasing microbial components that overstimulate the immune system, leading to greater tissue damage. Klebsiella pneumoniae is a gram-negative, rod-shaped bacteria of the family Enterobacteriaceae. Knowing about Klebsiella pneumoniae is extremely important in the present situation, as it is one of the major causal organisms of pneumonia. Internal and external factors of K. pneumoniae are responsible for the entry and multiplication inside the host. Antibiotics against K. pneumoniae are a class of Penicillins, Cephalosporins, Monobactams, and Carbapenems which have the β-lactam ring in common with variable side chains. Combating the antibiotics by synthesizing the enzymes like beta-lactamases is the main reason for the survival of these organisms against newer generation antibiotics. In this review, we have tried to discuss about Klebsiella pneumoniae, antibiotics, and their mechanism of action.

Monitoring of Enterobacteria strains with producing β-lactamases in males with infectious-inflammatory diseases of urogenital tract

This article presents the findings of investigation of the microflora of 257 males with infectious-inflammatory diseases of the urogenital tract using the test system “Androflor”. The role of representatives of conditionally pathogenic microflora as the main etiological agent in occurrence of infectious-inflammatory diseases of the urogenital tract in males was shown. Its composition in 39.3±3.0% of cases was represented by bacteria of family Enterobacteriaceae, in 10.9±1.9% – by Enterococcus spp., in 3.1±1.1% – by Haemophilus spp. and in 0.4±0.1% of cases – by P. aeruginosa. Out of 101 strains of enterobacteria, 27 representatives had the ability to synthesize β-lactamases 26.7±4.4% of cultures), in particular: 16 isolates of E. coli, 5 isolates of P. mirabilis and 6 isolates of K. pneumoniae. The selected strains of enterobacteria producing β-lactamases appeared to be resistant at least to 6 tested antibiotics, which allowed referring them to categories of multi-resistant. All cultures producing β-lactamases showed resistance to penicillinеs – ampicillin and amoxiclav. In this case, resistance to at least one of the antibiotics of cephalosporin group of the third generation was noted. In addition, 83.3±2.1% of the examined isolates were characterized by resistance to macrolides – erythromycin and azithromycin, as well as to co-trimoxazole and fosfomicin. The obtained data are of practical importance to develop efficient schemes of antibiotic therapy for infectious-inflammatory diseases of the urogenital tract, caused by strains of enterobacteria producing β-lactamases.

Genomic analysis of a novel active prophage of Hafnia paralvei.

Little is known about the prophages in Hafniaceae bacteria. A novel Hafnia phage, yong2, was induced from Hafnia paralvei by treatment with mitomycin C. The phage has an elliptical head with dimensions of approximately 45 × 38nm and a long noncontractile tail of approximately 157 × 4nm. The complete genome of Hafnia phage yong2 is a 39,546-bp double-stranded DNA with a G+C content of 49.9%, containing 59 open reading frames (ORFs) and having at least one fixed terminus (GGGGCAGCGACA). In phylogenetic analysis, Hafnia phage yong2 clustered with four predicted Hafnia prophages and one predicted Enterobacteriaceae prophage. These prophages and members of the family Drexlerviridae together formed two distinct subclades nested within a clade, suggesting the existence of a novel class of prophages with conserved sequences and a unique evolutionary status not yet studied before in Hafniaceae and Enterobacteriaceae bacteria.

Research Priorities on One Health: A Bibliometric Analysis.

ObjectiveOne Health is an emerging research area that has received increasing attention globally. In this study, we aimed to explore the global research trend and hotspots of One Health and provide a reference for potential future research and practices.MethodsThis was a bibliometric descriptive study of publications on One Health in four directions, including zoonotic diseases, antimicrobial resistance, food safety, and vector-borne infections. Publications from 2003 to 2021 were retrieved using the Scopus database on One Health, which were screened based on the PRISMA guidelines. Keywords were analyzed and visualized using VOSviewer software.ResultsA total of 12,815 publications were included. The annual number of publications and those on each topic showed a gradual increase from 181 in 2003 to 1,647 in 2020, with an average annual growth rate of about 20.2%; the top three countries in terms of the number of publications were the United States of America (n=3,588), the United Kingdom (n=1,429) and China (n=1,233); the major research subjects were mainly in the natural sciences, with fewer social sciences subjects involved (n = 312; 1%). The main research directions within the area of zoonotic diseases included viral, bacterial, parasitic zoonotic diseases, and vector-borne diseases, with a small amount of antimicrobial resistance research. The major research interests within antimicrobial resistance were Enterobacteriaceae drug-resistant bacteria, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and antimicrobial resistance gene detection; research on food safety clustered around agronomy research, aquaculture research as well as a small amount of antimicrobial resistance research in food; and research on vector-borne diseases focused on mosquito-borne infectious diseases, tick-borne infectious diseases, and vectors.ConclusionsThe scientific literature on One Health has witnessed a rising global trend. Most research has focused on the human-animal health interface, while environmental health is often neglected. Research subjects mainly fall within natural science disciplines, with less social science research. More support needs to be given to interdisciplinary and intersectoral cooperation and research in the future.

The Pork Meat or the Environment of the Production Facility? The Effect of Individual Technological Steps on the Bacterial Contamination in Cooked Hams.

The aim of this study was to analyse the influence of the contamination level of fresh meat on the bacterial population in raw material before cooking and on the microbiota of cooked hams following heat treatment. The effect of incubation temperatures of 6.5 and 15 °C on the results obtained was also evaluated during the bacteriological investigation. The total viable count (TVC), the number of Enterobacteriaceae and lactic acid bacteria (LAB) were determined in the samples. LAB were isolated from 13 samples out of the 50 fresh meat samples. The species most frequently detected included Latilactobacillus sakei, Leuconostoc carnosum, Enterococcus gilvus, Latilactobacillus curvatus, and Leuconostoc gelidum. The meat sampled after the brine injection and tumbler massaging showed higher bacterial counts compared to fresh meat samples (p < 0.001). The heat treatment destroyed the majority of the bacteria, as the bacterial counts were beneath the limit of detection with a few exceptions. Although the primary cultivation of samples of cooked hams did not reveal the presence of LAB, their presence was confirmed in 11 out of 12 samples by a stability test. Bacteria of the genus Leuconostoc were the most numerous.

Validation of the Soleris®Enterobacteriaceae Method for Detection of Enterobacteriaceae in Dried Cannabis Flower: AOAC Performance Tested MethodSM 121901.

The Soleris®Enterobacteriaceae vial is a growth-based, automated method for detection of bacteria of the family Enterobacteriaceae in foods and other sample types including nutraceuticals and cosmetics. The Soleris method is used in a "dilute-to-specification" or threshold manner, in which a result is scored as positive or negative around a predetermined cutoff (in CFU/g) established by the dilution and volume of sample homogenate tested. The Soleris method was granted AOAC Performance Tested MethodSM (PTM) status for select foods after successful completion of a validation study (PTM 121901). The objective of this study was to validate the method for the detection of Enterobacteriaceae in dried cannabis flower [>0.3% delta-9-tetrahydrocannabinol (THC)]. The matrix study included comparison of Soleris method presumptive results to confirmation from the Soleris vials, and comparison of the Soleris confirmed results to those of the ISO 21528-2:2017 colony count method. Test materials at four different levels of contamination ranging from 7.8 to 3500 CFU/g were tested at three dilutions, corresponding to test thresholds. Probability of detection analysis at P < 0.05 showed there were no significant differences between Soleris presumptive and confirmed results, and no significant differences between Soleris confirmed and ISO 21528-2:2017 results. The results provided evidence that the Soleris Enterobacteriaceae test is an accurate method for detection of Enterobacteriaceae in dried cannabis flower. The Soleris Enterobacteriaceae method provides cannabis industry QC personnel with an effective method for analysis of dried cannabis flower and produces results in 20-24 h.

Effect of virgin olive oil nanoemulsion combined with ajowan (Carum copticum) essential oil on the quality of lamb loins stored under chilled condition

This survey was conducted to evaluate the impact of virgin olive oil nanoemulsion (ONE) combined with ajowan (Carum copticum) essential oil (AEO) on quality of lamb loin under refrigerated condition. The treatments were control, ONE, ONE + 1% AEO, and ONE + 2% AEO. The treatments caused a delay in growth of mesophilic and psychrotrophic bacteria, Enterobacteriaceae, and lactic acid bacteria during chilled storage. The increasing rate of total volatile nitrogen content, lipid and protein oxidation, metmyoglobin formation, and color deterioration was more retarded in treatment groups. The treatments including ONE + 1% AEO and ONE + 2% AEO were more efficient than ONE alone to delay microbial flora growth, slow down oxidative processes, and improve color in the loins. According to the results of microbial, chemical, and sensory parameters, shelflife of lamb loins was 4 days in control, 8 days in ONE, and at least 16 days in ONE + 1% AEO and ONE + 2% AEO groups. In conclusion, combination of ONE and AEO is appropriate as natural preservative to extend the shelflife of lamb loins stored under chilled condition.

Antimicrobial Activity of Red Alga Flour (Gelidium sp.) and Its Effect on Quality Retention of Scomber scombrus during Refrigerated Storage.

This study analyzed the antimicrobial effect of aqueous extracts of flour obtained from red alga (Gelidium sp.) both in vitro, against most common food pathogenic and spoilage bacteria, and in a food model system during the chilled storage of Atlantic mackerel (Scomber scombrus). Results of in vitro assays allowed the conclusion that the aqueous flour extracts have antimicrobial activity against Gram-negative bacteria such as Enterobacteriaceae (Escherichia coli, Enterobacter aerogenes, and Klebsiella pneumoniae) and proteobacteria (Vibrio alginolyticus), and against Gram-positive bacteria such as Bacillus cereus and B. subtilis. In the food model study, different concentrations of the flour extract were present in the icing medium, microbial and chemical analyses being carried out in fish muscle at different storage times. An inhibitory effect (p < 0.05) on microbial growth (aerobes, psychrotrophs, Enterobacteriaceae, and proteolytic and lipolytic bacteria) and on chemical quality indices (pH, total volatile amines, and trimethylamine) was concluded. This effect was more pronounced when the flour extract concentration in the ice increased and at advanced storage times. This study provides a first approach to the beneficial use of flour of the alga Gelidium as a new preserving strategy for chilled fish.

Metagenomic identification of pathogenic bacteria for pneumonia from postmortem lung tissue

Pathologists have been concerned about the validity of bacterial cultures from lung tissue for the postmortem identification of pneumonia-associated pathogens. Therefore, we studied whether pathogenic bacteria that cause pneumonia could be identified via the metagenomic analysis of lung tissue sampled at autopsy from 11 pneumonia cases and nine non-pneumonia cases. We demonstrated that metagenomic analysis of the postmortem lung microbiota could identify a bacterial genus as a pneumonia pathogen when the genus was predominant and an established pathogen. However, it is important to diagnose Enterobacteriaceae or anaerobic bacteria as pneumonia pathogens, because their abundance in the lung microbiota of non-pneumonia cases supports postmortem translocation and replacement. Moreover, we confirmed that postmortem bacterial culture from lung tissue could be misleading for the identification of the pneumonia pathogen based on postmortem anaerobic changes and artificial culture conditions. To our knowledge, this study is the first to demonstrate the conditions under which metagenomic analysis of postmortem lung tissue can identify bacterial genera that cause pneumonia.

Distribution and drug resistance profiles of pathogens causing bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia.

To study the changes in the distribution and drug resistance profiles of pathogens causing bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia. The medical data were collected from the children with acute lymphoblastic leukemia who were admitted to the First Affiliated Hospital of Zhengzhou University between January 2015 and December 2020 and developed bloodstream infection after chemotherapy. The samples were divided into the first three years group and the next three years group according to the time of testing to investigate the differences in the distribution and drug resistance profiles of pathogens as time. A total of 235 strains of pathogens were isolated, among which there were 159 Gram-negative strains (67.7%; mainly Escherichia coli and Klebsiella pneumoniae), 61 Gram-positive strains (26.0%; mainly Staphylococcus epidermidis), and 15 strains of fungi (6.4%; mainly Candida albicans). There were no significant differences between the first three years group and the next three years group in the detection rate of Gram-negative bacteria (68.8% vs 66.9%, P>0.05) or Gram-positive bacteria (29.2% vs 23.7%, P>0.05). Compared with the first three years group, the next three years group had significant increases in the detection rate of Streptococcus mitis (5.8% vs 0.0%, P<0.05) and fungi (9.4% vs 2.1%, P<0.05). There was no significant difference in the drug resistance rate of Gram-negative or Gram-positive bacteria between the two groups (P>0.05). Enterobacteriaceae bacteria are the main pathogens of bloodstream infection after chemotherapy in children with acute lymphoblastic leukemia, while the detection rates of Streptococcus mitis and fungi tend to increase as time, which needs to be taken seriously in clinical practice.

Protective culture: Is it a solution to improve the quality of culture‐free white cheese?

The biggest problem faced by cheese producers is the textural and microbiological quality of culture-free white cheese types, known as shepherd’s cheese or cottage cheese among local people and produced widely throughout Turkey with high heat treatment. In the present study, commercial protective cultures containing two different subspecies of Lactobacillus rhamnosus and Lactobacillus plantarum were added separately to pasteurized milk. Physicochemical, textural, and microbiological properties were analyzed during the processing of cheese and 2 months of ripening. The results showed that L. plantarum was effective on yeast (1.29 log10 cfu/g reduction) and Staphylococcus aureus growth (1.61 log10 cfu/g reduction) and L. rhamnosus (one of the commercial cultures) was effective on coliform bacteria (1.70 log10 cfu/g reduction) compared with the control. Also, the Enterobacteriaceae count was lower than in other protective cultures that used cheese. Overall, the use of L. rhamnosus can be recommended for culture-free white cheese production in this study. Novelty impact statement Protective culture could be a novel approach to inhibit undesirable flora for white brined cheese. In this study, Danisco Holdbac LC culture limited the growth of Enterobacteriaceae and coliform bacteria. Moreover, the addition of Danisco Holdbac LC allowed the textural properties of this type of cheese to be preserved until the end of the ripening period.

Comparative genomic analyses of Polymyxin-resistant Enterobacteriaceae strains from China

BackgroundMobile colistin resistance like gene (mcr-like gene) is a new type of polymyxin resistance gene that can be horizontally transferred in the Enterobacteriaceae. This has brought great challenges to the treatment of multidrug-resistant Escherichia coli and K. pneumoniae.ResultsK. pneumoniae 16BU137 and E. coli 17MR471 were isolated from the bus and subway handrails in Guangzhou, China. K. pneumoniae 19PDR22 and KP20191015 were isolated from patients with urinary tract infection and severe pneumonia in Anhui, China. Sequence analysis indicated that the mcr-1.1 gene was present on the chromosome of E. coli 17MR471, and the gene was in the gene cassette containing pap2 and two copies of ISApl1.The mcr-1.1 was found in the putative IncX4 type plasmid p16BU137_mcr-1.1 of K. pneumoniae 16BU137, but ISApl1 was not found in its flanking sequence. Mcr-8 variants were found in the putative IncFIB/ IncFII plasmid pKP20191015_mcr-8 of K. pneumoniae KP20191015 and flanked by ISEcl1 and ISKpn26.ConclusionThis study provides timely information on Enterobacteriaceae bacteria carrying mcr-like genes, and provides a reference for studying the spread of mcr-1 in China and globally.

Microbiome analyses of 12 psyllid species of the family Psyllidae identified various bacteria including Fukatsuia and Serratia symbiotica, known as secondary symbionts of aphids

BackgroundPsyllids (Hemiptera: Psylloidea) comprise a group of plant sap-sucking insects that includes important agricultural pests. They have close associations not only with plant pathogens, but also with various microbes, including obligate mutualists and facultative symbionts. Recent studies are revealing that interactions among such bacterial populations are important for psyllid biology and host plant pathology. In the present study, to obtain further insight into the ecological and evolutionary behaviors of bacteria in Psylloidea, we analyzed the microbiomes of 12 psyllid species belonging to the family Psyllidae (11 from Psyllinae and one from Macrocorsinae), using high-throughput amplicon sequencing of the 16S rRNA gene.ResultsThe analysis showed that all 12 psyllids have the primary symbiont, Candidatus Carsonella ruddii (Gammaproteobacteria: Oceanospirillales), and at least one secondary symbiont. The majority of the secondary symbionts were gammaproteobacteria, especially those of the family Enterobacteriaceae (order: Enterobacteriales). Among them, symbionts belonging to “endosymbionts3”, which is a genus-level monophyletic group assigned by the SILVA rRNA database, were the most prevalent and were found in 9 of 11 Psyllinae species. Ca. Fukatsuia symbiotica and Serratia symbiotica, which were recognized only as secondary symbionts of aphids, were also identified. In addition to other Enterobacteriaceae bacteria, including Arsenophonus, Sodalis, and “endosymbionts2”, which is another genus-level clade, Pseudomonas (Pseudomonadales: Pseudomonadaceae) and Diplorickettsia (Diplorickettsiales: Diplorickettsiaceae) were identified. Regarding Alphaproteobacteria, the potential plant pathogen Ca. Liberibacter europaeus (Rhizobiales: Rhizobiaceae) was detected for the first time in Anomoneura mori (Psyllinae), a mulberry pest. Wolbachia (Rickettsiales: Anaplasmataceae) and Rickettsia (Rickettsiales: Rickettsiaceae), plausible host reproduction manipulators that are potential tools to control pest insects, were also detected.ConclusionsThe present study identified various bacterial symbionts including previously unexpected lineages in psyllids, suggesting considerable interspecific transfer of arthropod symbionts. The findings provide deeper insights into the evolution of interactions among insects, bacteria, and plants, which may be exploited to facilitate the control of pest psyllids in the future.

Simple and Rapid Detection of ESBL blaSHV gene from an Urban River in Tokyo by Loop-Mediated Isothermal Amplification.

Extended-spectrum β-lactamases (ESBLs) are produced mainly by gram-negative bacteria in Enterobacteriaceae. One of the major types of ESBLs is sulfhydryl variable (SHV) -type ESBL. Herein, we attempted to develop a simple and rapid method for the detection of the ESBL blaSHV gene by loop-mediated isothermal amplification (LAMP) . The five-primer set designed could amplify blaSHV gene at an isothermal temperature of 65℃. The detection limit of the LAMP method with the LF loop primer was 1 copy/tube, which was 10,000-fold more sensitive than that of the conventional PCR. The LAMP assay could also detect the direct amplification of blaSHV gene from a single river water sample in Tokyo. The LAMP method has great potential for applications in hospital, soil and water environment, food, and livestock.

GUT BACTERIAL DIVERSITY BETWEEN POLYGRID LAND SNAILS REFLECT ENVIRONMENTAL DIFFERENCES

GUT BACTERIAL DIVERSITY BETWEEN POLYGRID LAND SNAILS REFLECT ENVIRONMENTAL DIFFERENCES

The Cytotoxicity Effect Study of Fosfomycin and Mecillinam Antibiotic on Multi-Drug Resistant Klebsiella pneumoniae from Infected Urothelial Tissue

Enterobacteriaceae bacteria are clinically important and lead to various diseases associated with high mortality and morbidity, including urinary tract infections, yet their treatment is a challenge due to increasing antibiotic resistance. This study examined the cytotoxicity effects and viability-inducing abilities of mecillinam and fosfomycin antibiotics in the extended-spectrum beta-lactamase Klebsiella pneumoniae strain. The immortalized normal human urothelial cell line was used and the urothelial cell line and bacteria using Klebsiella pneumoniae cultures were prepared. The bacterial association assays with the urothelial cell line were then conducted. The cytotoxic effects were examined using cytotoxicity assays of Klebsiella pneumoniae, cefotaxime-Munich, ampicillinase C, oxacillinase and transmission electron microscopy on the immortalized normal human urothelial cell line. The cytotoxicity of fosfomycin and mecillinam on cell line cytotoxic assays were measured by lactate dehydrogenase, a cell death marker and visualized by hematoxylin. Klebsiella pneumoniae strains showed significantly reduced association with urothelial cells than cefotaxime-Munich strains. The cefotaxime-Munich and ampicillinase C had a higher association with the urothelial cells than the oxacillinase and transmission electron microscopy strains. The cytotoxicity assays indicated that all Klebsiella pneumoniae strains had increased cytotoxicity after 24 or 12 h of incubation. Antibiotic resistance is increased by the bacterial strains that have genes encoding resistance, such as cefotaxime-Munich, ampicillinase C, transmission electron microscopy and oxacillinase.

Raman spectroscopy for the differentiation of Enterobacteriaceae: a comparison of two methods.

Enterobacteriaceae are the leading cause of urinary tract infections, and include pathogens such as E. coli, K. pneumoniae and P. mirabilis. Due to their similarity, the correct identification of these pathogens is difficult and time-consuming. Raman spectroscopy has been demonstrated extensively as a tool for rapid microbiological differentiation. However, for pathogenic Enterobacteriaceae the application of Raman spectroscopy has been particularly challenging. In this study, two promising methods for Raman-based microbiological diagnostics were compared for differentiating Enterobacteriaceae. Spectra were collected from single-cells with Raman microspectroscopy and from colonies on agar with an NIR Raman fiber-probe. A comprehensive dataset of spectra from 8 different, clinically relevant, genera was collected. Visually, the spectra obtained from both methods presented little difference between the genera. For classification, single cell analysis yielded limited results, while the fiber-probe spectra enabled perfect classification of all 16 isolates. Moreover, the model was validated on new replicates and 15/16 strains were correctly identified (94% overall accuracy). This is the first study to focus on the closely related Enterobacteriaceae, who have previously been avoided or differentiated poorly. It shows how, with the correct spectroscopic setup, even challenging questions in clinical microbiology can be resolved with Raman spectroscopy, highlighting the method's potential for improving patient care.

Exploiting Caenorhabditis elegans to discover human gut microbiota-mediated intervention strategies in protein conformational diseases.

Exploiting Caenorhabditis elegans to discover human gut microbiota-mediated intervention strategies in protein conformational diseases.