Presence of the blaTEM Gene in Commensal Neisseria spp.: A Possible Cause for the Acquired Drug Resistance Among Pathogenic Respiratory Bacteria.

Background The oral microbiome consists of various bacterial genera, with Neisseria spp. being a prominent part of this niche. While Neisseria gonorrhoeae and Neisseria meningitidis are human-restricted pathogens, non-pathogenic Neisseria species like Neisseria sicca, Neisseria perflava, etc., are primarily commensals that can also behave as opportunistic pathogens. With increasing penicillin resistance in commensal Neisseria, there is a concern that these bacteria might harbor resistance genes that can be transferred to other pathogens. This study aimed to characterize the blaTEM gene (encodes for the plasmid-mediated ß-lactamase enzyme that hydrolyzes the ß-lactam ring) of commensal Neisseria spp. isolated from respiratory samples. Methodology The research was conducted in the Department of Clinical Microbiology at Sri Ramachandra University, Chennai. The specimens used were sputum and throat swabs, which were subjected to a series of phenotypic methods and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) for speciation. The antibiogram was determined using the Kirby-Bauer disk diffusion method, and a PCR assay was utilized to identify the blaTEM gene responsible for ß-lactamase production. Results Out of 274 processed samples, 65 unique commensal Neisseria spp. were identified. The study highlighted the presence of the blaTEM gene in 93.9% (61) of the isolates, which is responsible for ß-lactamase production. All isolates exhibited resistance to penicillin. Most blaTEM-positive commensal Neisseria spp. were susceptible to cefuroxime (83.6%), ceftriaxone (85.2%), and cefotaxime (85.2%). The high prevalence of the blaTEM gene in commensal Neisseria is alarming. The gene, found on plasmids, could potentially transfer to other related species like Neisseria gonorrhoeae and Neisseria meningitidis, as well as other Gram-negative bacilli. Conclusion The presence of resistance genes in commensal bacteria is of concern, as they might be reservoirs for resistance transfer to pathogenic strains. The study emphasizes the importance of continuous monitoring and deeper investigations into commensal bacteria, emphasizing the need for a broader community screening approach to understand resistance mechanisms in the normal microbiome.

Molecular identification of blaTEM gene of extended-spectrum beta-lactamase-producing Escherichia coli from healthy pigs in Malang district, East Java, Indonesia.

Objective: The increase and prevalence of multidrug-resistant bacteria in livestock animals are serious public health concerns. This study aimed to identify the presence of the blaTEM gene in extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolated from rectal swabs of apparently healthy pigs in Malang District, East Java, Indonesia. Materials and Methods: A total of 120 rectal swab samples were collected from the pigs. The rectal swabs were screened for the presence of E. coli using standard microbiological identification procedures. The Kirby-Bauer disk diffusion method identified multidrug-resistant E. coli. Five different classes of antibiotics were used to identify multidrug-resistant isolates, including Ciprofloxacin, Trimethoprim, Tetracycline, Streptomycin, and Aztreonam. Multidrug-resistant E. coli isolates were characterized for the presence of ESBL using double-disk synergy test methods. The presence of blaTEM genes was determined using polymerase chain reaction methods. Results: The results of this study indicated that 107 (89.2%) out of 120 samples analyzed were positive for E. coli isolates. A total of 32 (29.9%) E. coli isolates were identified to be multidrug-resistant and further subjected to molecular testing. The molecular analysis revealed (5; 15.6%) E. coli isolates to harbor the blaTEM gene. Conclusion: The results of this study revealed that pigs and products of pork origin must be considered a source of transmission of ESBL-producing E. coli to public health important under the food chain.

Molecular Characterization of Penicillinase-Producing Neisseria gonorrhoeae Isolated in Two Time Periods, 2003-2004 and 2014-2015, in Italy.

The emergence of antibiotic resistant strains poses a great concern for gonorrhea treatment. The aim of this study was to characterize penicillinase-producing Neisseria gonorrhoeae (PPNG) isolates collected in Italy in two time frames, 2003-2004 and 2014-2015. A total of 80 PPNG were characterized for the blaTEM gene variant and the plasmid type. Furthermore, gonococci were typed using Neisseria gonorrhoeae multiantigen sequence typing. Antibiotic susceptibility assay was performed for penicillin, ciprofloxacin, ceftriaxone, and spectinomycin by Etest and minimum inhibitory concentration (MIC) test strip methods. The ß-lactamase production was detected using nitrocefin test. Among PPNG isolates, four blaTEM alleles were identified as follows: blaTEM-1, blaTEM-228, blaTEMP14S, and blaTEM-135. The African plasmid possessed the blaTEM-1, blaTEM-228, and blaTEMP14S, whereas blaTEM-135 was identified in Toronto/Rio and Asian plasmids. The percentage of isolates with the blaTEM-1-carrying African plasmid increased from 42.5% in 2003-2004 to 55% in 2014-2015; conversely, the isolates with blaTEM-135-carrying Toronto/Rio plasmid decreased from 57.5% to 35%. Among the isolates carrying the Toronto/Rio plasmids possessing blaTEM-135, sequence type (ST)661 and ST5624 were found to be the predominant STs in both periods 2003-2004 and 2014-2015, respectively. More than half of the PPNG isolates were resistant to ciprofloxacin. Increase in the isolates carrying the African plasmid possessing blaTEM-1 and a parallel decrease of the blaTEM-135-carrying Toronto/Rio plasmid was observed. Moreover, PPNG isolate harbored Toronto/Rio plasmid with blaTEM-135 belonged mainly to two major STs (ST661 and ST5624). Given the possible role of a mutated blaTEM gene as an additional mechanism to extended spectrum ß-lactamase resistance, it is crucial to monitor gonococci carrying these resistance genes.

Prevalence of ß-lactam (bla TEM) and Metronidazole (nim) Resistance Genes in the Oral Cavity of Greek Subjects.

OBJECTIVES: The aim of this study is to investigate the prevalence of bla TEM and nim genes that encode resistance to ß-lactams and nitroimidazoles, respectively, in the oral cavity of systemically healthy Greek subjects. MATERIALS AND METHODOLOGY: After screening 720 potentially eligible subjects, 154 subjects were recruited for the study, including 50 periodontally healthy patients, 52 cases of gingivitis and 52 cases of chronic periodontitis. The clinical parameters were assessed with an automated probe. Various samples were collected from the tongue, first molars and pockets >6mm, and analysed by polymerase chain reaction-amplification of the bla TEM and nim genes, using primers and conditions previously described in the literature. RESULTS: There was a high rate of detection of bla TEM in plaque and tongue samples alike in all periodontal conditions (37% of plaque and 60% of tongue samples, and 71% of participants). The bla TEM gene was detected more frequently in the tongue samples of the periodontally healthy (56%) and chronic periodontitis (62%) groups compared to the plaque samples from the same groups (36% and 29%, respectively; z-test with Bonferroni corrections-tests, P<0.05). The nim gene was not detected in any of the 343 samples analysed. CONCLUSION: The oral cavity of Greek subjects often harbours bla TEM but not nim genes, and therefore the antimicrobial activity of ß-lactams might be compromised.

Molecular detection and antimicrobial resistance of Pseudomonas aeruginosa from houseflies (Musca domestica) in Iran.

BACKGROUND: Pseudomonas aeruginosa is a common bacterium that can cause disease in humans and other animals. This study was conducted to screen for molecular detection and antimicrobial-resistant P. aeruginosa in Musca domestica in different locations in the Iranian provinces of Shahrekord and Isfahan. METHODS: Musca domestica were captured by both manual and sticky trap methods, during the daytime, from household kitchens, cattle farms, animal hospitals, human hospitals, slaughterhouses and chicken farms at random locations in Shahrekord and Isfahan provinces of Iran, and subsequently transported to the laboratory for detection of P. aeruginosa. In the laboratory, flies were identified and killed by refrigeration in a cold chamber at -20 °C, then placed in 5 mL peptone water and left at room temperature for five hours before being processed. Pseudomonas isolates were preliminarily identified to genus level based on colony morphology and gram staining, and their identity was further confirmed by polymerase chain reaction. RESULTS: Overall blaTEM gene was recovered from 8.8 % (53/600) of the P. aeruginosa isolated from houseflies collected from the two provinces. A slightly higher prevalence (10.7 %; 32/300) was recorded in Shahrekord province than Isfahan province (7.0 %; 21/300). The locations did not differ statistically (p < 0.05) in bacterial prevalence in flies. Seasonal prevalence showed a significantly lower infection frequency during autumn. CONCLUSIONS: Houseflies are important in the epidemiology of P. aeruginosa infections.

Molecular detection and antimicrobial resistance of Pseudomonas aeruginosa from houseflies (Musca domestica) in Iran

Background Pseudomonas aeruginosa is a common bacterium that can cause disease in humans and other animals. This study was conducted to screen for molecular detection and antimicrobial-resistant P. aeruginosa in Musca domestica in different locations in the Iranian provinces of Shahrekord and Isfahan. Methods Musca domestica were captured by both manual and sticky trap methods, during the daytime, from household kitchens, cattle farms, animal hospitals, human hospitals, slaughterhouses and chicken farms at random locations in Shahrekord and Isfahan provinces of Iran, and subsequently transported to the laboratory for detection of P. aeruginosa. In the laboratory, flies were identified and killed by refrigeration in a cold chamber at −20 °C, then placed in 5 mL peptone water and left at room temperature for five hours before being processed. Pseudomonas isolates were preliminarily identified to genus level based on colony morphology and gram staining, and their identity was further confirmed by polymerase chain reaction. Results Overall blaTEM gene was recovered from 8.8 % (53/600) of the P. aeruginosa isolated from houseflies collected from the two provinces. A slightly higher prevalence (10.7 %; 32/300) was recorded in Shahrekord province than Isfahan province (7.0 %; 21/300). The locations did not differ statistically (p < 0.05) in bacterial prevalence in flies. Seasonal prevalence showed a significantly lower infection frequency during autumn. Conclusions Houseflies are important in the epidemiology of P. aeruginosa infections.

Molecular detection and antimicrobial resistance of Pseudomonas aeruginosa from houseflies (Musca domestica) in Iran

BackgroundPseudomonas aeruginosa is a common bacterium that can cause disease in humans and other animals. This study was conducted to screen for molecular detection and antimicrobial-resistant P. aeruginosa in Musca domestica in different locations in the Iranian provinces of Shahrekord and Isfahan.MethodsMusca domestica were captured by both manual and sticky trap methods, during the daytime, from household kitchens, cattle farms, animal hospitals, human hospitals, slaughterhouses and chicken farms at random locations in Shahrekord and Isfahan provinces of Iran, and subsequently transported to the laboratory for detection of P. aeruginosa. In the laboratory, flies were identified and killed by refrigeration in a cold chamber at −20 °C, then placed in 5 mL peptone water and left at room temperature for five hours before being processed. Pseudomonas isolates were preliminarily identified to genus level based on colony morphology and gram staining, and their identity was further confirmed by polymerase chain reaction.ResultsOverall blaTEM gene was recovered from 8.8 % (53/600) of the P. aeruginosa isolated from houseflies collected from the two provinces. A slightly higher prevalence (10.7 %; 32/300) was recorded in Shahrekord province than Isfahan province (7.0 %; 21/300). The locations did not differ statistically (p < 0.05) in bacterial prevalence in flies. Seasonal prevalence showed a significantly lower infection frequency during autumn.ConclusionsHouseflies are important in the epidemiology of P. aeruginosa infections.(AU)

Phenotypic and Genotypic Methods for Detection of Extended Spectrum ß Lactamase Producing Escherichia coli and Klebsiella pneumoniae Isolated from Ventilator Associated Pneumonia.

BACKGROUND: Ventilator Associated Pneumonia (VAP) is one of the common nosocomial infections associated with high morbidity due to multidrug resistant pathogens. Rapid spread of resistance to broad spectrum beta-lactams in pathogenic strains causes antibiotics ineffectiveness and increased severity of illness. The CTX-M is the most dominant Extended Spectrum ß Lactamase (ESBL) among Enterobacteriaceae in many regions of the world. The aim of the study was to identify the occurrence of ESBL and detect the genes responsible for ESBL production by conventional Polymerase Chain Reaction (PCR) method. METHODS: This prospective study included patients, clinically diagnosed as VAP. Endotracheal aspirates (EA) were collected and cultured by quantitative method. The bacterial isolates were identified as per standard methods. Isolates resistant to 3(rd) generation cephalosporins were screened for ESBL production by disk approximation method and combination disc diffusion method. Isolates confirmed as ESBL producers were subjected to genotyping by conventional PCR. STATISTICAL ANALYSIS: Statistical analysis was done by using MS Excel sheet. Descriptive statistics like percentage was done in the study. RESULTS: Among the isolates from 428 patients who developed VAP, 144 isolates belonged to the Enterobacteriaceae family (Klebsiella pneumoniae 87 and Escherichia coli 57). A total of 66 isolates (28 Klebsiella pneumoniae and 38 Escherichia coli) were confirmed as ESBL producer by disc approximation method and 63 isolates by double disc combination method. In the present study by conventional PCR bla CTX-M was the common gene in 48.5% strains followed by 22.22% bla SHV and 14.81% bla TEM. CONCLUSION: The genotypic methods using specific PCR amplification of resistance genes seems to have 100% specificity and sensitivity in detection of ESBL when compared to phenotypic methods which lacks the constant sensitivity.

Resistance to ß-lactams in bacteria isolated from different types of Portuguese cheese.

The purpose of this study was to investigate the presence of beta-lactam-resistant bacteria in six different types of Portuguese cheese. The numbers of ampicillin resistant (AMP(r)) bacteria varied from 4.7 x 10(2) to 1.5 x 10(7) CFU/g. Within 172 randomly selected beta-lactam-resistant bacteria, 44 resistant phenotypes were found and 31.4% were multidrug resistant. The majority (85%) of the isolates identified belonged to the Enterobacteriaceae family. The presence of the bla(TEM) gene was detected in 80.9% of the tested isolates. The results suggest that without thermal processing of the milk and good hygienic practices, cheese may act as a vehicle of transfer of beta-lactam-resistant bacteria to the gastrointestinal tract of consumers.