Identification of Stenotrophomonas maltophilia strains isolated from environmental and clinical samples: a rapid and efficient procedure

Venom-microbiomics of eight species of Neotropical spiders from the Theraphosidae family

AIM

Tarantulas are one of the largest predatory arthropods in tropical regions. Tarantulas though not lethal to humans, their venomous bite kills small animals and insect upon which they prey. To understand the abiotic and biotic components involved in Neotropical tarantula bites, we conducted a venom-microbiomics study in eight species from Costa Rica.

METHODS AND RESULTS

We determined that the toxin profiles of tarantula venom are highly diverse using shotgun proteomics; the most frequently encountered toxins were ω-Ap2 toxin, neprilysin-1, and several teraphotoxins. Through culture-independent and culture-dependent methods, we determined the microbiota present in the venom and excreta to evaluate the presence of pathogens that could contribute to primary infections in animals, including humans. The presence of opportunistic pathogens with hemolytic activity was observed, with a prominence of Stenotrophomonas in the venoms. Other bacteria found in venoms and excreta with hemolytic activity included members of the genera Serratia, Bacillus, Acinetobacter, Microbacterium, and Morganella.

CONCLUSIONS

Our data shed light on the venom- and gut-microbiome associated with Neotropical tarantulas. This information may be useful for treating bites from these arthropods in both humans and farm animals, while also providing insight into the toxins and biodiversity of this little-explored microenvironment.

High-Throughput Short Sequence Typing Schemes for Pseudomonas aeruginosa and Stenotrophomonas maltophilia Pure Culture and Environmental DNA

Molecular typing techniques are utilized to determine genetic similarities between bacterial isolates. However, the use of environmental DNA profiling to assess epidemiologic links between patients and their environment has not been fully explored. This work reports the development and validation of two high-throughput short sequence typing (HiSST) schemes targeting the opportunistic pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia, along with a modified SM2I selective medium for the specific isolation of S. maltophilia. These HiSST schemes are based on four discriminative loci for each species and demonstrate high discriminating power, comparable to pairwise whole-genome comparisons. Each scheme includes species-specific PCR primers for precise differentiation from closely related taxa, without the need for upstream culture-dependent methods. For example, the primers targeting the bvgS locus make it possible to distinguish P. aeruginosa from the very closely related Pseudomonas paraeruginosa sp. nov. The selected loci included in the schemes are adapted to massive parallel amplicon sequencing technology. An R-based script implemented in the DADA2 pipeline was assembled to facilitate HiSST analyses for efficient and accurate genotyping of P. aeruginosa and S. maltophilia. We demonstrate the performance of both schemes through in silico validations, assessments against reference culture collections, and a case study involving environmental samples.

Evaluation of phenotypical and genotypical methods for the identification and typing of Stenotrophomonas maltophilia isolated from a pharmaceutical facility

AIMS

Evaluate methods for identification and typing of Stenotrophomonas maltophilia isolated from a pharmaceutical facility.

METHODS AND RESULTS

From 270 S. maltophilia strains identified by VITEK®2, 40 were selected and submitted to MALDI TOF-MS, 16S and 23S rRNA gene analysis, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and an antimicrobial susceptibility profile. 16S rRNA sequencing was able to identify 39 (97.5%) strains as Stenotrophomonas spp. and one (2.5%) as Luteimonas huabeiensis. MALDI TOF-MS identified 37 (92.5%) strains as S. maltophilia, and three (7.5%) were not identified. PCR targeting 23S rRNA yielded a positive result for 39 (97.5%) strains. However, after sequencing, two strains were identified as Stenotrophomonas rhizophila, showing false-positive results. The confirmed S. maltophilia strains (n = 37) showed 35 distinct ERIC-PCR profiles and exhibited sensitivity to minocycline and levofloxacin, and six (16.3%) showed intermediate resistance to sulfamethoxazole-trimethoprim.

CONCLUSION

Matrix-assisted laser desorption lonization-time of flight mass spectrometry (MALDI-TOF MS) was a satisfactory methodology for the identification of S. maltophilia, but expansion of the database is necessary for the identification of other species. 16S rDNA sequencing showed low resolution for Stenotrophomonas species differentiation. PCR targeting 23S rRNA could not differentiate S. maltophilia from S. rhizophila. ERIC-PCR was shown to be a useful tool for the microbial source tracking of S. maltophilia.

Relationship between antibiotic resistance with class 1 integron and SmeDEF efflux pump encoding genes in clinical isolates of Stenotrophomonas maltophilia

Stenotrophomonas maltophilia is an emerging multidrug-resistant organism with an increasing frequency of hospital-acquired infections predominantly in developing countries. The purpose of this study was to determine the antibiotic resistance and frequency of the smeD, class 1 integron, and sul1 genes in clinical isolates of S. maltophilia in two Iranian provinces. From January 2020 to September 2021, 38 clinical isolates of S. maltophilia were collected from patients in hospitals in Tabriz and Sanandaj provinces of Iran. S. maltophilia isolates were confirmed by standard bacteriological tests and 16S rRNA gene PCR. Disk diffusion and the MIC test strip methods were used to determine the antibiotic resistance patterns. PCR was performed to investigate the presence of smeD, class 1 integron, and sul1 genes. The antimicrobial test for the isolated S. maltophilia showed a high level of sensitivity against most of the antibiotics used. Maximum sensitivity was recorded for ciprofloxacin (100% (38/38)) and levofloxacin 100% (38/38), followed by ceftazidime (97.36% (37/38)), trimethoprim-sulfamethoxazole (81.57% (31/38)), ticarcillin-clavulanate (60.52% (23/38)), and piperacillin-tazobactam (55.26% (21/38)). We observed a high prevalence of smeD (100% (38/38)) and class 1 integron (94.73% (36/38)) genes in the isolates, and none of the isolates carried the sul1 gene. The findings from this study indicate that resistance to trimethoprim-sulfamethoxazole was not observed, and still, trimethoprim-sulfamethoxazole is the best drug with desirable antimicrobial effect in the treatment of nosocomial infections caused by S. maltophilia strains. Despite the observation of a high number of class 1 integron, the sul1 gene was not observed, which indicates the role of this gene in high-level trimethoprim-sulfamethoxazole resistance and not having a role in low-level resistance. Based on our results, clinical microbiology laboratories need continuous surveillance of resistance rates to trimethoprim-sulfamethoxazole, because of the possibility of S. maltophilia acquiring trimethoprim-sulfamethoxazole-resistance by mobile gen elements.

Versatility of Stenotrophomonas maltophilia: Ecological roles of RND efflux pumps

S. maltophilia is a widely distributed bacterium found in natural, anthropized and clinical environments. The genome of this opportunistic pathogen of environmental origin includes a large number of genes encoding RND efflux pumps independently of the clinical or environmental origin of the strains. These pumps have been historically associated with the uptake of antibiotics and clinically relevant molecules because they confer resistance to many antibiotics. However, considering the environmental origin of S. maltophilia, the ecological role of these pumps needs to be clarified. RND efflux systems are highly conserved within bacteria and encountered both in pathogenic and non-pathogenic species. Moreover, their evolutionary origin, conservation and multiple copies in bacterial genomes suggest a primordial role in cellular functions and environmental adaptation. This review is aimed at elucidating the ecological role of S. maltophilia RND efflux pumps in the environmental context and providing an exhaustive description of the environmental niches of S. maltophilia. By looking at the substrates and functions of the pumps, we propose different involvements and roles according to the adaptation of the bacterium to various niches. We highlight that i°) regulatory mechanisms and inducer molecules help to understand the conditions leading to their expression, and ii°) association and functional redundancy of RND pumps and other efflux systems demonstrate their complex role within S. maltophilia cells. These observations emphasize that RND efflux pumps play a role in the versatility of S. maltophilia.

In vitro study to evaluate the antimicrobial activity of various multifunctional cosmetic ingredients and chlorphenesin on bacterial species at risk in the cosmetic industry

AIMS

We evaluated the activity of the preservative chlorphenesin and of four antimicrobial cosmetic multifunctional ingredients against various strains of gram-negative and gram-positive human opportunistic pathogens.

METHODS AND RESULTS

Growth kinetics, modelling growth parameters and statistical analyses enabled comparing bacterial behaviour in the presence and in the absence of the compound. Whatever compound tested (i.e. chlorphenesin, phenylpropanol, hexanediol, ethylhexylglycerin, hydroxyacetophenone) and strain origin (i.e. clinical versus industrial), the growth of 42 strains belonging to Acinetobacter spp., Burkholderia cepacia complex and Stenotrophomonas maltophilia, was totally inhibited. On the opposite all of the P. aeruginosa strains (n = 13) as well as 4 and 6 out of 10 strains of Pluralibacter gergoviae grew in the presence of chlorphenesin and ethylhexylglycerin, respectively. Some P. gergoviae and Staphylococcus hominis strains withstand hydroxyacetophenone. Within a species, the different strains show variable latency phase, growth rate (r) and carrying capacity (K). They can be similar, lower or higher than those measured in control conditions.

CONCLUSIONS

Data showed differences in the antimicrobial activity of compounds. Upon exposure, strains differed in their behaviour between and within species. Whatever species and strains, compound sensitivity could not be related to antibiotic resistance.

SIGNIFICANCE AND IMPACT OF THE STUDY

Most multifunctional ingredients showed significant antimicrobial properties against the wide panel of species and strains evaluated. This will help adjusting preservation strategies in the cosmetic industry.

Dephytinizing and Probiotic Potentials of Saccharomyces cerevisiae (NCIM 3662) Strain for Amelioration of Nutritional Quality of Functional Foods

Increase of undigested complexes of phytic acid in food is gaining serious attention to overcome nutritional challenges due to chelation effects. We investigated soil-borne yeast phytase from Saccharomyces cerevisiae (NCIM 3662) for dephytinization of foods, probiotic properties, and process development. The strain produced 45 IU/DCG by cell-bound phytase in an unoptimized medium was increased fourfold (164 IU/DCG) in 12 h using statistical media optimization. The process was scaled-up up to 10-L fermenter scale with increased phytase productivity of 6.4 IU/DCG/h as compared to the lab scale. The strain displayed probiotic characteristics like tolerance to artificial gastric acid conditions, hydrophobicity, autoaggregation, coaggregation, and bile salt hydrolase (BSH) activity. Further, it could dephytinize (removal of phytic acid; an anti-nutritional factor) functional foods like ragi (finger millet) flour, soya flour, chickpea flour, and poultry animal feed. A combination of cell-bound dephytinizing phytase and nutrition-ameliorating probiotic traits of S. cerevisiae (NCIM 3662) presents profound applications in food technology sector.

Quantitative real-time PCR assay for the rapid identification of the intrinsically multidrug-resistant bacterial pathogen Stenotrophomonas maltophilia

Stenotrophomonas maltophilia is emerging as an important cause of disease in nosocomial and community-acquired settings, including bloodstream, wound and catheter-associated infections. Cystic fibrosis (CF) airways also provide optimal growth conditions for various opportunistic pathogens with high antibiotic tolerance, including S. maltophilia. Currently, there is no rapid, cost-effective and accurate molecular method for detecting this potentially life-threatening pathogen, particularly in polymicrobial specimens, suggesting that its true prevalence is underestimated. Here, we used large-scale comparative genomics to identify a specific genetic target for S. maltophilia, with subsequent development and validation of a real-time PCR assay for its detection. Analysis of 167 Stenotrophomonas spp. genomes identified a conserved 4 kb region in S. maltophilia, which was targeted for Black Hole Quencher assay design. Our assay yielded the positive detection of 89 of 89 (100%) clinical S. maltophilia strains, and no amplification of 23 non-S. maltophilia clinical isolates. S. maltophilia was detected in 10 of 16 CF sputa, demonstrating the assay's utility for direct detection in respiratory specimens. The assay demonstrated good sensitivity, with limits of detection and quantitation on pure culture of ~10 and ~100 genome equivalents, respectively. Our assay provides a highly specific, sensitive and cost-effective method for the accurate identification of S. maltophilia, and will improve the diagnosis and treatment of this under-recognized pathogen by enabling its accurate and rapid detection from polymicrobial clinical and environmental samples.

Metagenomic Analysis Identified Stenotrophomonas maltophilia Pneumonia in an Infant Suffering From Unexplained Very Severe Pneumonia

Pneumonia poses a significant global morbidity and mortality burden on children. Etiological diagnosis and matched anti-microbial therapy are particularly important for very severe pneumonia. Although great advances have been achieved in diagnostic approaches, it remains challenging to identify pathogens in unexplained pneumonia (UP) cases. In this study, we applied next-generation sequencing (NGS) technology and a metagenomic approach to detect and characterize respiratory bactiera in an UP case in infant. Stenotrophomonas maltophilia was the only bacterial pathogen detected in blood. Metagenomic sequencing also provided bacteria genomic sequences, which could be used to evaluate the role of this pathogen in the disease. This NGS method has the potential to improve the identification of causative organisms in patients with pneumonia and the delivery of appropriate, pathogen-directed antibiotic therapy.

Survival and growth of Stenotrophomonas maltophilia in free-living amoebae (FLA) and bacterial virulence properties

Stenotrophomonas maltophilia is found ubiquitously in the environment and is an important emerging nosocomial pathogen. S. maltophilia has been recently described as an Amoebae-Resistant Bacteria (ARB) that exists as part of the microbiome of various free-living amoebae (FLA) from waters. Co-culture approaches with Vermamoeba vermiformis demonstrated the ability of this bacterium to resist amoebal digestion. In the present study, we assessed the survival and growth of six environmental and one clinical S. maltophilia strains within two amoebal species: Acanthamoeba castellanii and Willaertia magna. We also evaluated bacterial virulence properties using the social amoeba Dictyostelium discoideum. A co-culture approach was carried out over 96 hours and the abundance of S. maltophilia cells was measured using quantitative PCR and culture approach. The presence of bacteria inside the amoeba was confirmed using confocal microscopy. Our results showed that some S. maltophilia strains were able to multiply within both amoebae and exhibited multiplication rates up to 17.5 and 1166 for A. castellanii and W. magna, respectively. In contrast, some strains were unable to multiply in either amoeba. Out of the six environmental S. maltophilia strains tested, one was found to be virulent. Surprisingly, this strain previously isolated from a soil amoeba, Micriamoeba, was unable to infect both amoebal species tested. We further performed an assay with a mutant strain of S. maltophilia BurA1 lacking the efflux pump ebyCAB gene and found the mutant to be more virulent and more efficient for intra-amoebal multiplication. Overall, the results obtained strongly indicated that free-living amoebae could be an important ecological niche for S. maltophilia.

Increased diet breadth of little brown bats (Myotis lucifugus) at their northern range limit: a multimethod approach

The distribution of small mammals is constrained by extreme environmental demands and variable food supplies that are commonly incurred at northern latitudes. Little brown bats (Myotis lucifugus (Le Conte, 1831)) are at the northwestern limits of their range in Alaska (USA), where environmental demands are higher and prey availability is more seasonal than elsewhere in their range. We hypothesized that the little brown bat in interior Alaska has adjusted to these constraints by broadening its foraging niche, relative to that of southern conspecifics. We analyzed arthropod fragments (microhistology) in guano to describe prey composition to order. We compared the efficacy of evaluating diet by microhistology with DNA analysis and stable isotope analysis on guano and hair. Bats consumed aerial prey such as Lepidoptera (moths) and Diptera (true flies and mosquitoes), as well as terrestrial arthropods including Araneae (spiders). Shifts in the proportion of aerial prey in the diet were closely linked to ordinal day. Values for δ15N in hair indicated that bats were generalists in interior Alaska, coastal Alaska, and the Yukon (Canada), but significant outliers indicated that some individuals have distinct diets. The little brown bat’s flexibility in feeding strategies likely allows this species to sustain populations in arctic and subarctic regions.

Stenotrophomonas maltophilia as an Emerging Ubiquitous Pathogen: Looking Beyond Contemporary Antibiotic Therapy

Stenotrophomonas maltophilia is a commensal and an emerging pathogen earlier noted in broad-spectrum life threatening infections among the vulnerable, but more recently as a pathogen in immunocompetent individuals. The bacteria are consistently being implicated in necrotizing otitis, cutaneous infections including soft tissue infection and keratitis, endocarditis, meningitis, acute respiratory tract infection (RTI), bacteraemia (with/without hematological malignancies), tropical pyomyositis, cystic fibrosis, septic arthritis, among others. S. maltophilia is also an environmental bacteria occurring in water, rhizospheres, as part of the animals' microflora, in foods, and several other microbiota. This review highlights clinical reports on S. maltophilia both as an opportunistic and as true pathogen. Also, biofilm formation as well as quorum sensing, extracellular enzymes, flagella, pili/fimbriae, small colony variant, other virulence or virulence-associated factors, the antibiotic resistance factors, and their implications are considered. Low outer membrane permeability, natural MDR efflux systems, and/or resistance genes, resistance mechanisms like the production of two inducible chromosomally encoded β-lactamases, and lack of carefully compiled patient history are factors that pose great challenges to the S. maltophilia control arsenals. The fluoroquinolone, some tetracycline derivatives and trimethoprim-sulphamethaxole (TMP-SMX) were reported as effective antibiotics with good therapeutic outcome. However, TMP-SMX resistance and allergies to sulfa together with high toxicity of fluoroquinolone are notable setbacks. S. maltophilia's production and sustenance of biofilm by quorum sensing enhance their virulence, resistance to antibiotics and gene transfer, making quorum quenching an imperative step in Stenotrophomonas control. Incorporating several other proven approaches like bioengineered bacteriophage therapy, Epigallocatechin-3-gallate (EGCG), essential oil, nanoemulsions, and use of cationic compounds are promising alternatives which can be incorporated in Stenotrophomonas control arsenal.

Evolutionary Genetic Analysis Uncovers Multiple Species with Distinct Habitat Preferences and Antibiotic Resistance Phenotypes in the Stenotrophomonas maltophilia Complex

The genus Stenotrophomonas (Gammaproteobacteria) has a broad environmental distribution. Stenotrophomonas maltophilia is its best known species because it is a globally emerging, multidrug-resistant (MDR), opportunistic pathogen. Members of this species are known to display high genetic, ecological and phenotypic diversity, forming the so-called S. maltophilia complex (Smc). Heterogeneous resistance and virulence phenotypes have been reported for environmental Smc isolates of diverse ecological origin. We hypothesized that this heterogeneity could be in part due to the potential lumping of several cryptic species in the Smc. Here we used state-of-the-art phylogenetic and population genetics methods to test this hypothesis based on the multilocus dataset available for the genus at pubmlst.org. It was extended with sequences from complete and draft genome sequences to assemble a comprehensive set of reference sequences. This framework was used to analyze 108 environmental isolates obtained in this study from the sediment and water column of four rivers and streams in Central Mexico, affected by contrasting levels of anthropogenic pollution. The aim of the study was to identify species in this collection, defined as genetically cohesive sequence clusters, and to determine the extent of their genetic, ecological and phenotypic differentiation. The multispecies coalescent, coupled with Bayes factor analysis was used to delimit species borders, together with population genetic structure analyses, recombination and gene flow estimates between sequence clusters. These analyses consistently revealed that the Smc contains at least 5 significantly differentiated lineages: S. maltophilia and Smc1 to Smc4. Only S. maltophilia was found to be intrinsically MDR, all its members expressing metallo-β-lactamases (MBLs). The other Smc lineages were not MDR and did not express MBLs. We also obtained isolates related to S. acidaminiphila, S. humi and S. terrae. They were significantly more susceptible to antibiotics than S. maltophilia. We demonstrate that the sympatric lineages recovered display significantly differentiated habitat preferences, antibiotic resistance profiles and β-lactamase expression phenotypes, as shown by diverse multivariate analyses and robust univariate statistical tests. We discuss our data in light of current models of bacterial speciation, which fit these data well, stressing the implications of species delimitation in ecological, evolutionary and clinical research.

Occurrence of Stenotrophomonas maltophilia in agricultural soils and antibiotic resistance properties

The occurrence of Stenotrophomonas maltophilia was monitored in organic amendments and agricultural soils from various sites in France and Tunisia. S. maltophilia was detected in horse and bovine manures, and its abundance ranged from 0.294 (±0.509) × 10(3) to 880 (±33.4) × 10(3) CFU (g drywt)(-1) of sample. S. maltophilia was recovered from most tested soil samples (104/124). Its abundance varied from 0.33 (±0.52) to 414 (±50) × 10(3) CFU (g drywt)(-1) of soil and was not related to soil characteristics. Antibiotic resistance properties of a set of environmental strains were compared to a clinical set, and revealed a high diversity of antibiotic resistance profiles, given both the numbers of resistance and the phenotypes. Manure strains showed resistance phenotypes, with most of the strains resisting between 7 and 9 antibiotics. While French soil strains were sensitive to most antibiotics tested, some Tunisian strains displayed resistance phenotypes close to those of clinical French strains. Screening for metal resistance among 66 soil strains showed a positive relationship between antibiotic and metal resistance. However, the prevalence of antibiotic resistance phenotypes in the studied sites was not related to the metal content in soil samples.

Comparative Genomics of Environmental and Clinical Stenotrophomonas maltophilia Strains with Different Antibiotic Resistance Profiles

Stenotrophomonas maltophilia, a ubiquitous Gram-negative γ-proteobacterium, has emerged as an important opportunistic pathogen responsible for nosocomial infections. A major characteristic of clinical isolates is their high intrinsic or acquired antibiotic resistance level. The aim of this study was to decipher the genetic determinism of antibiotic resistance among strains from different origins (i.e., natural environment and clinical origin) showing various antibiotic resistance profiles. To this purpose, we selected three strains isolated from soil collected in France or Burkina Faso that showed contrasting antibiotic resistance profiles. After whole-genome sequencing, the phylogenetic relationships of these 3 strains and 11 strains with available genome sequences were determined. Results showed that a strain's phylogeny did not match their origin or antibiotic resistance profiles. Numerous antibiotic resistance coding genes and efflux pump operons were revealed by the genome analysis, with 57% of the identified genes not previously described. No major variation in the antibiotic resistance gene content was observed between strains irrespective of their origin and antibiotic resistance profiles. Although environmental strains generally carry as many multidrug resistant (MDR) efflux pumps as clinical strains, the absence of resistance-nodulation-division (RND) pumps (i.e., SmeABC) previously described to be specific to S. maltophilia was revealed in two environmental strains (BurA1 and PierC1). Furthermore the genome analysis of the environmental MDR strain BurA1 showed the absence of SmeABC but the presence of another putative MDR RND efflux pump, named EbyCAB on a genomic island probably acquired through horizontal gene transfer.

Rapid identification of Stenotrophomonas maltophilia by peptide nucleic acid fluorescence in situ hybridization

The objective of this study was to develop a novel peptide nucleic acid (PNA) probe for Stenotrophomonas maltophilia identification by fluorescence in situ hybridization (FISH). The probe was evaluated using 33 human and veterinary clinical S. maltophilia isolates and 45 reference strains representing common bacterial species in the respiratory tract. The probe displayed 100% sensitivity and 100% specificity on pure cultures and allowed detection in sputum from cystic fibrosis patients. The detection limit was 10⁴ CFU/mL in spiked tracheal aspirate and bronchoalveolar lavage from healthy horses. Altogether the study shows that this species-specific PNA FISH probe facilitates rapid detection of S. maltophilia in biological specimens.

A specific polymerase chain reaction method to identify Stenotrophomonas maltophilia

Stenotrophomonas maltophilia is a multidrug-resistant nosocomial pathogen that is difficult to identify unequivocally using current methods. Accordingly, because the presence of this microorganism in a patient may directly determine the antimicrobial treatment, conventional polymerase chain reaction (PCR) and real-time PCR assays targeting 23S rRNA were developed for the specific identification of S. maltophilia. The PCR protocol showed high specificity when tested against other species of Stenotrophomonas, non-fermentative Gram-negative bacilli and 100 clinical isolates of S. maltophilia previously identified using the Vitek system.

Phenotype microarray technology and its application in industrial biotechnology

Phenotype microarray (PM) technology provides an insight into the metabolic profiling of microbial cells within 96-well plate system. The PM assay allows for cells to be assessed for utilisation of nutrients or sensitivity to toxic compounds. The assay utilises a redox sensitive tetrazolium dye which becomes irreversibly reduced upon detection of cellular metabolic output, detection is synchronous with a colour change from colourless to purple. Output from PM technology can be measured visually or quantified by reader the absorbance in each well. PM technology has highlighted differences in growth requirements, nutrient utilisation, sensitivity to toxins, and genetic diversity in bacteria, fungi and mammalian cells.

Development of rapid phenotypic system for the identification of Gram-negative oxidase-positive bacilli in resource-limited settings

Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microbiology. The diagnosis and surveillance of diseases is dependent, to a great extent, on laboratory services, which cannot function without effective reliable reagents and diagnostics. Despite the advancement in microbiology diagnosis globally, resourcelimited countries still struggle to provide an acceptable diagnosis quality which helps in clinical disease management and improve their mortality and morbidity data. During this study an indigenous product, Quick Test Strip (QTS) NE, was developed for the rapid identification of biochemically slower group of Gram-negative oxidase-positive bacilli that covers 19 different bacterial genera. Some of the members belonging to these groups are well-established human pathogens, e.g. various species of Vibrio, Pseudomonas, Burkholderia, Aeromonas, Achromobacter and Stenotrophomonas. This study also evaluates the performance of QTS-NE by comparing with genotypic characterization methods. A total of 232 clinical and reference bacterial isolates were tested by three different methods. QTSNE provides 100 percent concordant results with other rapid identification and molecular characterization methods and confirms the potential to be used in clinical diagnosis.