Antibiotic resistant Escherichia coli strains in healthy pets from Tamaulipas, Mexico.

Antibiotic resistance constitutes a significant public health challenge, with diverse reservoirs of resistant bacteria playing pivotal roles in their dissemination. Among these reservoirs, pets are carrying antibiotic-resistant strains. The objective of this study was to assess the resistance profiles of Escherichia coli, and the prevalence of extended-spectrum ß-lactamase (ESBL) producing E. coli strains in dogs and cats from Tamaulipas, Mexico. A total of 300 stool samples (150 dogs and 150 cats) from healthy pets were subjected to analysis. Antibiotic susceptibility testing and the identification of ESBLs were carried out by disc diffusion method. The presence of resistance genes, class 1, 2, and 3 integrons (intI1, intI2, and intI3) and phylogroups was determined by PCR analysis. The findings reveal that 42.6% (128/300) of the strains exhibited resistance to at least one of the eight antibiotics assessed, and 18.6% (56/300) demonstrated multidrug resistance (MDR), that distributed across 69 distinct resistance patterns. Altogether 2.6% of E. coli strains (8/300) were confirmed as TEM and CTX-M type ESBL producers. These outcomes underscore the roles of dogs and cats in Tamaulipas as reservoirs for the dissemination of MDR and/or ESBL strains. The results underscore the necessity for conducting prevalence studies on ESBL-producing E. coli, forming a foundation for comprehending the present scenario and formulating strategies for the control and mitigation of this issue.

The Global Rise of ESBL-Producing Escherichia coli in the Livestock Sector: A Five-Year Overview.

ß-lactam antibiotics are a key element in the treatment of bacterial infections. However, the excessive use of these antibiotics has contributed to the emergence of ß-lactam-resistant enterobacteria, including Escherichia coli. One of the main challenges facing the public health sector is antibacterial resistance (ABR), mainly due to limited options in its pharmacological treatment. Currently, extended-spectrum ß-lactamases (ESBLs) present an alarming situation, as there is an increase in morbidity and mortality rates, prolonged hospital stays, and increased costs for sanitary supplies, which involve not only humans but also the environment and animals, especially animals destined for food production. This review presents an analysis of the prevalence of ESBL-producing E. coli and its distribution in different animal sources throughout the world, providing an understanding of the association with resistance and virulence genes, as well as perceiving the population structure of E. coli.

Prevalence and Antimicrobial Resistance of Listeria monocytogenes in Different Raw Food from Reynosa, Tamaulipas, Mexico.

Listeria (L.) monocytogenes is an opportunistic foodborne pathogen that causes listeriosis in humans and animals, reaching up to 30% case mortality. There are only a few reports in Mexico about the L. monocytogenes strains found in various foods. The aim of this study was to determine the prevalence of L. monocytogenes, serogroups, virulence genes, and antimicrobial resistance in different foods from Reynosa, Tamaulipas, Mexico. L. monocytogenes strains were characterized by microbiological and molecular methods. Susceptibility to 12 antibiotics was determined according to CLSI and EUCAST. A total of 300 samples of seafood, pasteurized and raw milk, cheese, beef, and chicken were collected from supermarkets and retail markets. The presence of L. monocytogenes was detected in 5.6% of the samples. Most strains belonged to serogroups 4b, 4d, and 4e (68.4%). All strains presented a minimum of four virulence genes; the most common were actA, hly, and plcB (92.1%). A high percentage of antimicrobial susceptibility was observed, with resistance only to STX-TMP (78.9%), STR (26.3%), MEM (21.0%), and E (2.6%). These results show that the foods in Reynosa, Tamaulipas, are a reservoir of L. monocytogenes and represent a potential health risk.

Ligand- and Structure-Based Virtual Screening Identifies New Inhibitors of the Interaction of the SARS-CoV-2 Spike Protein with the ACE2 Host Receptor.

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a fast-spreading viral pathogen and poses a serious threat to human health. New SARS-CoV-2 variants have been arising worldwide; therefore, is necessary to explore more therapeutic options. The interaction of the viral spike (S) protein with the angiotensin-converting enzyme 2 (ACE2) host receptor is an attractive drug target to prevent the infection via the inhibition of virus cell entry. In this study, Ligand- and Structure-Based Virtual Screening (LBVS and SBVS) was performed to propose potential inhibitors capable of blocking the S receptor-binding domain (RBD) and ACE2 interaction. The best five lead compounds were confirmed as inhibitors through ELISA-based enzyme assays. The docking studies and molecular dynamic (MD) simulations of the selected compounds maintained the molecular interaction and stability (RMSD fluctuations less than 5 Å) with key residues of the S protein. The compounds DRI-1, DRI-2, DRI-3, DRI-4, and DRI-5 efficiently block the interaction between the SARS-CoV-2 spike protein and receptor ACE2 (from 69.90 to 99.65% of inhibition) at 50 µM. The most potent inhibitors were DRI-2 (IC50 = 8.8 µM) and DRI-3 (IC50 = 2.1 µM) and have an acceptable profile of cytotoxicity (CC50 > 90 µM). Therefore, these compounds could be good candidates for further SARS-CoV-2 preclinical experiments.

Antimicrobial resistance, virulence genes, and ESBL (Extended Spectrum Beta-Lactamase) production analysis in E. coli strains from the Rio Grande/Rio Bravo River in Tamaulipas, Mexico.

The Rio Grande/Rio Bravo River is used as a major water supply for diverse recreational, household, and industrial activities in Northeast Tamaulipas, Mexico, and South Texas. In this study, we sampled surface water from 38 sites along Rio Grande/Rio Bravo River (Díaz Ordaz, Reynosa and Matamoros). We isolated 105 E. coli strains that were molecularly and phenotypically characterized. The percentage of virulence genes detected in E. coli were: hlyA (15.23%), stx2 (11.42%), stx1 (9.52%), bfp (0.95%), and eae (0.0) and combinations of stx1/stx2 (2.85%), stx2/hlyA (1.90%), stx1/bfp (0.95%) and stx2/bfp (0.95%) were detected in these strains. Resistance to more than one antibiotic was detected in 85.71%, and 5.71% of strains were extended-spectrum ß-lactamase-E. coli (ESBL-EC). These results indicate the presence of potentially pathogenic E. coli strains in the Rio Grande/Rio Bravo River; therefore, it can be considered a reservoir of pathogenic strains and represents a health risk for the population.

Genomic Analysis of Multidrug-Resistant Escherichia coli Strains Isolated in Tamaulipas, Mexico.

The global spread of antimicrobial resistance genes (ARGs) is a major public health concern. Mobile genetic elements (MGEs) are the main drivers of this spread by horizontal gene transfer (HGT). Escherichia coli is widespread in various environments and serves as an indicator for monitoring antimicrobial resistance (AMR). Therefore, the objective of this work was to evaluate the whole genome of multidrug-resistant E. coli strains isolated from human clinical, animal, and environmental sources. Four E. coli strains previously isolated from human urine (n = 2), retail meat (n = 1), and water from the Rio Grande River (n = 1) collected in northern Tamaulipas, Mexico, were analyzed. E. coli strains were evaluated for antimicrobial susceptibility, followed by whole genome sequencing and bioinformatic analysis. Several ARGs were detected, including blaCTX-M-15, blaOXA-1, blaTEM-1B, blaCMY-2, qnrB, catB3, sul2, and sul3. Additionally, plasmid replicons (IncFIA, IncFIB, IncFII, IncY, IncR, and Col) and intact prophages were also found. Insertion sequences (ISs) were structurally linked with resistance and virulence genes. Finally, these findings indicate that E. coli strains have a large repertoire of resistance determinants, highlighting a high pathogenic potential and the need to monitor them.

Ligand-Based and Structure-Based Virtual Screening of New Sodium Glucose Cotransporter Type 2 Inhibitors.

BACKGROUND: Diabetes mellitus is a metabolic disease that causes multiple complications and common comorbidities, which decreases the quality of life for people affected by the disease. Sodium glucose cotransporter type 2 (SGLT2) participates in the reabsorption of 90% of glucose in the kidneys; therefore, it is an attractive drug target for controlling blood glucose levels. OBJECTIVE: The aim in this work was to obtain new potential SGLT2 inhibitors. METHODS: A ligand-based virtual screening (LBVS) from the ZINC15, PubChem and ChemSpider databases using the maximum common substructure (MCS) scaffold was performed. RESULT: A total of 341 compounds were obtained and analyzed by molecular docking on the active site of SGLT2. Subsequently, 15 compounds were selected for molecular dynamics (MD) simulation analysis. The compounds derived of spiroketal Sa1, Sa4, and Sa9 (≤ 3.5 Å) in complex with the receptor SGLT2 showed good stability during 120 ns of MD. CONCLUSION: These compounds are proposed as potential SGLT2 inhibitors.

Analysis of Giardia lamblia Nucleolus as Drug Target: A Review.

Giardia lamblia (G. lamblia) is the main causative agent of diarrhea worldwide, affecting children and adults alike; in the former, it can be lethal, and in the latter a strong cause of morbidity. Despite being considered a predominant disease in low-income and developing countries, current migratory flows have caused an increase in giardiasis cases in high-income countries. Currently, there is a wide variety of chemotherapeutic treatments to combat this parasitosis, most of which have potentially serious side effects, such as genotoxic, carcinogenic, and teratogenic. The necessity to create novel treatments and discover new therapeutic targets to fight against this illness is evident. The current review centers around the controversial nucleolus of G. lamblia, providing a historical perspective that traces its apparent absence to the present evidence supporting its existence as a subnuclear compartment in this organism. Additionally, possible examples of ncRNAs and proteins ubiquitous to the nucleolus that can be used as targets of different therapeutic strategies are discussed. Finally, some examples of drugs under research that could be effective against G. lamblia are described.

Extended-Spectrum ß-Lactamase-Producing Escherichia coli Isolated from Food-Producing Animals in Tamaulipas, Mexico.

Extended-spectrum ß-lactamase (ESBL)-producing E. coli has become an important global problem for the public health sector. This study aims to investigate the E. coli antimicrobial resistance profile among living food-producing animals in Tamaulipas, Mexico. A total of 200 fecal samples were collected from bovines, pigs, chickens and sheep. A total of 5.0% of the strains were phenotypically confirmed as ESBL producers. A high percentage of phenotypic antimicrobial resistance was observed against gentamicin (93.3%), tetracycline (86.6%) and streptomycin (83.3%). The gentamicin-resistant strains showed MDR, distributed among 27 resistance patterns to different antimicrobials. The antimicrobial resistance gene tet(A) was detected in 73.3% of isolates, aadA1 in 60.0% and sul2 in 43.3% of strains. The blaCTX-M gene was found in 23.3% of strains. The virulence gene hlyA was detected in 43.3% of isolates; stx1 and stx2 were not detected in any strain. The phylotyping indicated that the isolates belonged to groups A (33.3%), B1 (16.6%), B2 (40.0%) and D (10.0%). These results show that food-producing animals might be a reservoir of ESBL-producing bacteria and may play a role in their spread.

Molecular and Antimicrobial Susceptibility Characterization of Escherichia coli Isolates from Bovine Slaughterhouse Process.

Antimicrobials are routinely used in human and veterinary medicine. With repeated exposure, antimicrobials promote antibiotic resistance, which poses a threat to public health. In this study, we aimed to determine the susceptibility patterns, virulence factors, and phylogroups of E. coli isolates during the killing process in a bovine slaughterhouse. We analyzed 336 samples (from water, surfaces, carcasses, and feces), and 83.3% (280/336) were positive for E. coli. The most common phenotypic resistances that we detected were 50.7% (142/280) for tetracycline, 44.2% (124/280) for cephalothin, 34.6% (97/280) for streptomycin, and 36.7% (103/280) for ampicillin. A total of 82.4% of the isolates had resistance for at least one antimicrobial, and 37.5% presented multiresistance. We detected a total of 69 different phenotypic resistance patterns. We detected six other resistance-related genes, the most prevalent being tetA (22.5%) and strB (15.7%). The prevalence values of the virulence genes were 5.4% in hlyA, 1.4% in stx1, and 0.7% in stx2. The frequencies of the pathogenic strains (B2 and D) were 32.8% (92/280) and 67.1% (188/280) as commensals A and B1, respectively. E. coli isolates with pathogenic potential and multiresistance may represent an important source of dissemination and a risk to consumers.

Evaluation of Retail Meat as a Source of ESBL Escherichia coli in Tamaulipas, Mexico.

In recent decades, the appearance of a group of strains resistant to most ß-lactam antibiotics, called extended-spectrum ß-lactamases (ESBLs), has greatly impacted the public health sector. The present work aimed to identify the prevalence of ESBL-producing Escherichia coli strains in retail meat from northeast Tamaulipas. A total of 228 meat samples were obtained from 76 different stores. A prevalence of E. coli ESBL of 6.5% (15/228) was detected. All (15/15) of the ESBL strains were multiresistant. Altogether, 40% (6/15) of the strains showed the presence of class 1 integrons. The isolates identified with blaCTX-M (20%) also showed co-resistance with the tet (A and B), str (A and B), and sul (2 and 3) genes. A total of 20% of the strains belonged to the B2 and D phylogroups, which are considered pathogenic groups. None of the ESBL-positive strains contained any of the virulence gene factors tested. The presence of ESBL-producing E. coli strains in meat indicates a potential risk to the consumer. Although most of these strains were classified as commensals, they were found to serve as reservoirs of multiresistance to antimicrobials and, therefore, are potential routes of dispersion of this resistance to other bacteria.

Identification and Characterization of the CRISPR/Cas System in Staphylococcus aureus Strains From Diverse Sources.

The CRISPR-Cas [clustered regularly interspaced short palindromic repeats and the CRISPR-associated genes (Cas)] system provides defense mechanisms in bacteria and archaea vs. mobile genetic elements (MGEs), such as plasmids and bacteriophages, which can either be harmful or add sequences that can provide virulence or antibiotic resistance. Staphylococcus aureus is a Gram-positive bacterium that could be the etiological agent of important soft tissue infections that can lead to bacteremia and sepsis. The role of the CRISPR-Cas system in S. aureus is not completely understood since there is a lack of knowledge about it. We analyzed 716 genomes and 1 genomic island from GENOMES-NCBI and ENA-EMBL searching for the CRISPR-Cas systems and their spacer sequences (SSs). Our bioinformatic analysis shows that only 0.83% (6/716) of the analyzed genomes harbored the CRISPR-Cas system, all of them were subtype III-A, which is characterized by the presence of the cas10/csm1 gene. Analysis of SSs showed that 91% (40/44) had no match to annotated MGEs and 9% of SSs corresponded to plasmids and bacteriophages, indicating that those phages had infected those S. aureus strains. Some of those phages have been proposed as an alternative therapy in biofilm-forming or infection with S. aureus strains, but these findings indicate that such antibiotic phage strategy would be ineffective. More research about the CRISPR/Cas system is necessary for a bigger number of S. aureus strains from different sources, so additional features can be studied.

Prevalence, antimicrobial resistance and virulence genes of Escherichia coli isolated from retail meat in Tamaulipas, Mexico.

OBJECTIVES: The aim of this study was to determinate the prevalence of Escherichia coli and its resistance to antimicrobials and the presence of virulence genes in retail samples of beef and pork in several locations in Tamaulipas, Mexico. METHODS: A total of 106 samples (54 beef and 52 pork) collected from August 2013 to March 2014 were analysed to detect E. coli isolates. The E. coli isolates were then analysed for detection of virulence factors and antimicrobial resistance genes. Antimicrobial susceptibility to 16 antimicrobial agents was also determined. RESULTS: A total of 158 E. coli isolates were obtained, among which 3 (1.9%) harboured the virulence gene stx1, 28 (17.7%) harboured stx2 and 34 (21.5%) harboured hlyA. High phenotypic resistance was observed in almost all isolates, since 146 (92.4%) showed a multiresistant phenotype with resistance to cefalotin (92%), ampicillin (92%), cefotaxime (78%), nitrofurantoin (76%) and tetracycline (75%). The antimicrobial resistance genes tet(A) and tet(B) were detected in 56% of isolates, strA in 9.6%, aadA in 17% and aac(3)-IV in only 0.6% of strains. CONCLUSIONS: Based on these results, it can be concluded that retail beef and pork meat may play a role in the spread of antimicrobial-resistant E. coli strains in this region.