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.

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.

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.

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.

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.

In vitro and In vivo Biological Activity of Two Aryloxy-naphthoquinones in Mice Infected with Trypanosoma cruzi Strains.

BACKGROUND: Chagas disease, a condition caused by Trypanosoma cruzi, is an endemic disease in Latin American countries that affects approximately eight million people worldwide. It is a continuing public health problem. As nifurtimox and benznidazole are the two pharmacological treatments currently used to treat it, the present research proposes new therapeutic alternatives. Previous studies conducted on naphthoquinone derivatives have found interesting trypanocidal effects on epimastigotes, with the molecules 2-phenoxy-1,4-naphthoquinone (IC50= 50 nM and SI < 250) and 2-(3-nitrophenoxy)-naphthalene-1,4-dione (IC50= 20 nM y SI=625) presenting the best biological activity. METHOD: The present study evaluated the efficacy of in vitro, ex vivo and in vivo models of two aryloxyquinones, 2-phenoxy-1,4-naphthoquinone (1) and 2-(3-nitrophenoxy)-naphthalene-1,4- dione (2), against two Mexican T. cruzi strains in both their epimastigote and blood Trypomastigote stage. Both compounds were evaluated against T. cruzi using a mouse model (CD1) infected with Mexican isolates of T. cruzi, nifurtimox and benznidazole used as control drugs. Finally, the cytotoxicity of the two compounds against the J774.2 mouse macrophage cell line was also determined. RESULT: The in vitro and in vivo results obtained indicated that both quinones were more active than the reference drugs. Compound 1 presents in vivo activity, showing up to 40% parasite reduction after 8 h of administration, a finding which is 1.25 times more effective than the results obtained using nifurtimox. CONCLUSION: These are encouraging results for proposing new naphthoquinone derivatives with potential anti-T. cruzi activity.

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.

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.

Characterization of triatomine bloodmeal sources using direct Sanger sequencing and amplicon deep sequencing methods.

Knowledge of host associations of blood-feeding vectors may afford insights into managing disease systems and protecting public health. However, the ability of methods to distinguish bloodmeal sources varies widely. We used two methods-Sanger sequencing and amplicon deep sequencing-to target a 228 bp region of the vertebrate Cytochrome b gene and determine hosts fed upon by triatomines (n = 115) collected primarily in Texas, USA. Direct Sanger sequencing of PCR amplicons was successful for 36 samples (31%). Sanger sequencing revealed 15 distinct host species, which included humans, domestic animals (Canis lupus familiaris, Ovis aries, Gallus gallus, Bos taurus, Felis catus, and Capra hircus), wildlife (Rattus rattus, Incilius nebulifer, Sciurus carolinensis, Sciurus niger, and Odocoileus virginianus), and captive animals (Panthera tigris, Colobus spp., and Chelonoidis carbonaria). Samples sequenced by the Sanger method were also subjected to Illumina MiSeq amplicon deep sequencing. The amplicon deep sequencing results (average of 302,080 usable reads per sample) replicated the host community revealed using Sanger sequencing, and detected additional hosts in five triatomines (13.9%), including two additional blood sources (Procyon lotor and Bassariscus astutus). Up to four bloodmeal sources were detected in a single triatomine (I. nebulifer, Homo sapiens, C. lupus familiaris, and S. carolinensis). Enhanced understanding of vector-host-parasite networks may allow for integrated vector management programs focusing on highly-utilized and highly-infected host species.

Azospirillum spp. from Plant Growth-Promoting Bacteria to Their Use in Bioremediation.

Xenobiotic contamination, a worldwide environmental concern, poses risks for humans, animals, microbe health, and agriculture. Hydrocarbons and heavy metals top the list of toxins that represent a risk to nature. This review deals with the study of Azospirillum sp., widely reported as plant growth-promoting bacteria in various cultures. However, its adaptation properties in adverse environments make it a good candidate for studying remediation processes in environments polluted with hydrocarbons and heavy metals. This review includes studies that address its properties as a plant growth promoter, its genomics, and that evaluate its potential use in the remediation of hydrocarbons and heavy metals.

Draft Genome Sequence of a Uropathogenic Escherichia coli Sequence Type 44 Strain Carrying Multiple Antimicrobial Resistance Genes.

Escherichia coli is a reservoir of antimicrobial resistance genes (ARGs). Here, we report the draft genome sequence of an E. coli strain (31HGR-CBG) that was isolated from a urine sample in Tamaulipas, Mexico. 31HGR-CBG harbors multiple ARGs, including blaCTX-M-15 and class 1 integron. This strain also carries multiple virulence genes.

RDRioMycobacterium tuberculosis strains associated with isoniazid resistance in Northern Mexico.

BACKGROUND: It has been established that the genomic background of Mycobacterium tuberculosis may influence disease progression, in particular for the Beijing family and the Latin American and Mediterranean (LAM)/RDRio strains. The purpose of this study was to evaluate the prevalence of the LAM/RDRio genotype in cases of tuberculosis from Mexico and their drug susceptibility profile. METHODS: Two hundred eighteen M. tuberculosis isolates were screened by 43-spacer spoligotyping. The LAM/RDRio genotype was confirmed by multiplex PCR, and the drug susceptibility testing was carried out in solid Löwenstein-Jensen media. RESULTS: Among the LAM strains identified, 24 (63.1%) were confirmed as M. tuberculosis RDRio. All RDRio strains shared the RD174 deletion, that was associated with isoniazid resistance (p=0.0264). CONCLUSIONS: We documented for the first time the isolation of the LAM/RDRio genotype in pulmonary cases of tuberculosis in Mexico, and we found resistance to the first-line anti-tuberculosis drug isoniazid in these strains.

Advances in Control Strategies against Spodoptera frugiperda. A Review.

The strategies for controlling the insect pest Spodoptera frugiperda have been developing over the past four decades; however, the insecticide resistance and the remarkable adaptability of this insect have hindered its success. This review first analyzes the different chemical compounds currently available and the most promising options to control S. frugiperda. Then, we analyze the metabolites obtained from plant extracts with antifeedant, repellent, insecticide, or ovicide effects that could be environmentally friendly options for developing botanical S. frugiperda insecticides. Subsequently, we analyze the biological control based on the use of bacteria, viruses, fungi, and parasitoids against this pest. Finally, the use of sex pheromones to monitor this pest is analyzed. The advances reviewed could provide a wide panorama to guide the search for new pesticidal strategies but focused on environmental sustainability against S. frugiperda.

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.

Virtual Screening of FDA-Approved Drugs against Triose Phosphate Isomerase from Entamoeba histolytica and Giardia lamblia Identifies Inhibitors of Their Trophozoite Growth Phase.

Infectious diseases caused by intestinal protozoan, such as Entamoeba histolytica (E. histolytica) and Giardia lamblia (G. lamblia) are a worldwide public health issue. They affect more than 70 million people every year. They colonize intestines causing primarily diarrhea; nevertheless, these infections can lead to more serious complications. The treatment of choice, metronidazole, is in doubt due to adverse effects and resistance. Therefore, there is a need for new compounds against these parasites. In this work, a structure-based virtual screening of FDA-approved drugs was performed to identify compounds with antiprotozoal activity. The glycolytic enzyme triosephosphate isomerase, present in both E. histolytica and G. lamblia, was used as the drug target. The compounds with the best average docking score on both structures were selected for the in vitro evaluation. Three compounds, chlorhexidine, tolcapone, and imatinib, were capable of inhibit growth on G. lamblia trophozoites (0.05-4.935 µg/mL), while folic acid showed activity against E. histolytica (0.186 µg/mL) and G. lamblia (5.342 µg/mL).

Multidrug Resistance of Escherichia coli Strains Isolated From Bovine Feces and Carcasses in Northeast Mexico.

In this work, the antimicrobial resistance profile of Escherichia coli strains (n = 248) isolated from bovine feces and carcass samples from Tamaulipas, Mexico, was evaluated. Susceptibility to 12 antibiotics conventionally used in human and veterinary treatments was determined according to Clinical and Laboratory Standards Institute guidelines. Genes encoding resistance to tetracycline (tetA and tetB), streptomycin (strA), aminoglycoside (aadA), and ß-lactamase (bla TEM and bla SHV) were investigated by PCR. Also, stx1, stx2, eae, bfp, and hlyA encoding virulence factors were determined. Of the isolates, 85.9% were confirmed as E. coli strains. Among the 213 E. coli isolates tested, 94.8% (202/213) showed resistance for at least one antimicrobial, mainly ampicillin (83.0%; 177/213), cephalothin (76.0%; 162/213), and tetracyclines (69.0%; 147/213). In all the other antibiotics tested, the resistance percentage was below 36%. A multidrug-resistant phenotype was found in 72.7% of the tested strains. The presence of the tet gene (tetA or tetB) was detected in 43.1% of the isolates, the strA gene in 17.3%, and aadA1 in 51.6%. The bla TEM and bla SHV genes were found in 10.3 and 0.4% of the isolates, respectively. stx1 was detected in 4.2% of isolates, stx2 in 7.0, and hlyA in 2.8%. The virulence genes, eae and bfp, were not detected in any strain. These results indicate that Tamaulipas food products of bovine origin can be a source of multiresistant E. coli strains for the environment and exposure for consumers.

Recent Advances in the Development of Broad-Spectrum Antiprotozoal Agents.

Infections caused by Trypanosoma brucei, Trypanosoma cruzi, Leishmania spp., Entamoeba histolytica, Giardia lamblia, Plasmodium spp., and Trichomonas vaginalis, are part of a large list of human parasitic diseases. Together, they cause more than 500 million infections per year. These protozoa parasites affect both low- and high-income countries and their pharmacological treatments are limited. Therefore, new and more effective drugs in preclinical development could improve overall therapy for parasitic infections even when their mechanisms of action are unknown. In this review, a number of heterocyclic compounds (diamidine, guanidine, quinoline, benzimidazole, thiazole, diazanaphthalene, and their derivatives) reported as antiprotozoal agents are discussed as options for developing new pharmacological treatments for parasitic diseases.

RDRioMycobacterium tuberculosis strains associated with isoniazid resistance in Northern Mexico.

BACKGROUND: It has been established that the genomic background of Mycobacterium tuberculosis may influence disease progression, in particular for the Beijing family and the Latin American and Mediterranean (LAM)/RDRio strains. The purpose of this study was to evaluate the prevalence of the LAM/RDRio genotype in cases of tuberculosis from Mexico and their drug susceptibility profile. METHODS: Two hundred eighteen M. tuberculosis isolates were screened by 43-spacer spoligotyping. The LAM/RDRio genotype was confirmed by multiplex PCR, and the drug susceptibility testing was carried out in solid Löwenstein-Jensen media. RESULTS: Among the LAM strains identified, 24 (63.1%) were confirmed as M. tuberculosis RDRio. All RDRio strains shared the RD174 deletion, that was associated with isoniazid resistance (p=0.0264). CONCLUSIONS: We documented for the first time the isolation of the LAM/RDRio genotype in pulmonary cases of tuberculosis in Mexico, and we found resistance to the first-line anti-tuberculosis drug isoniazid in these strains.