Description of extraintestinal pathogenic Escherichia coli based on phylogenetic grouping, virulence factors, and antimicrobial susceptibility.

Background and Objectives: Extraintestinal pathogenic Escherichia coli (ExPEC) is a recently recognized and highly diverse pathotype of E. coli. Its significance as a pathogen has increased due to the emergence of hypervirulent and multidrug-resistant (MDR) strains. The aim of this study was to characterize ExPEC isolates from humans based on their phylogenetic group, virulence factor profile, and antimicrobial susceptibility. Materials and Methods: The isolates were collected from patients with extraintestinal infections caused by E. coli, including urinary tract infections, bacteremia, and surgical site infections. The E. coli phylogenetic groups were determined using multiplex PCR. Additionally, the isolates were evaluated for their biofilm-forming abilities, susceptibility to antimicrobial agents, and presence of virulence genes. Results: In this study, the isolates were classified into four phylogenetic groups: A (48.3%), B2 (25.8%), D (19.35%), and B1 (6.45%). All isolates exhibited at least one of the ten analyzed virulence factors. However, there was no direct evidence linking a specific phylogenetic group to a particular virulence factor. Nevertheless, the presence of the fimH, fyuA, ompT, traT, and kpsMTII virulence genes was correlated with the production of strong biofilms, multidrug resistance (MDR), and the production of alpha hemolysin. Conclusion: This study provides a description of the phylogenetic groups in ExPEC and their potential association with virulence factor profiles and antimicrobial susceptibility.

Identification of the nasopharyngeal carriage of Neisseria meningitidis by 16S rRNA Gene sequencing in asymptomatic adolescents and young adults in Cartagena, Colombia (2019-2020).

The bacterium Neisseria meningitidis, a strictly human pathogen, can cause meningitis, meningococcemia, sepsis, and death; repeatedly it scause outbreaks around the world. The frequency of asymptomatic carriage is often high in adolescents and young adults, increasing the invasive meningococcal disease risk and likelihood of transmission. However, detailed analyses of meningococcal carriage in this population in Colombia, particularly in coastal areas, are lacking. In this study, the prevalence and characteristics of Neisseria meningitidis carriage were evaluated in asymptomatic adolescents and young adults (11-25 years old) in Cartagena, Colombia. Oropharynx samples were collected from participants between August and December 2019. The phenotypic identification of bacteria was performed by conventional methods and biochemical testing. Molecular identification to the species level was performed by 16S rRNA gene sequencing. In total, 12 of 648 samples were positive for Neisseria meningitidis by 16S rRNA sequencing, indicating a prevalence of 1.9%. Isolates were classified into four invasive serogroups (A, B, C, and W) by a comparative sequence analysis of the ribosomal gene. Despite the occurrence of meningococcal disease in Cartagena city in the last several years, the frequency of oropharyngeal carriage in adolescents and young adults was low. Serogroup A had not been previously reported in nasopharyngeal samples in Colombia. This is the first report of Neisseria meningitidis on the Colombian Caribbean coast based on 16S rRNA sequencing and is expected to guide the development of vaccination and follow-up strategies.

Identification of the nasopharyngeal carriage of Neisseria meningitidis by 16S rRNA Gene sequencing in asymptomatic adolescents and young adults in Cartagena, Colombia (2019-2020)

Abstract The bacterium Neisseria meningitidis, a strictly human pathogen, can cause meningitis, meningococcemia, sepsis, and death; repeatedly it scause outbreaks around the world. The frequency of asymptomatic carriage is often high in adolescents and young adults, increasing the invasive meningococcal disease risk and likelihood of transmission. However, detailed analyses of meningococcal carriage in this population in Colombia, particularly in coastal areas, are lacking. In this study, the prevalence and characteristics of Neisseria meningitidis carriage were evaluated in asymptomatic adolescents and young adults (11-25 years old) in Cartagena, Colombia. Oropharynx samples were collected from participants between August and December 2019. The phenotypic identification of bacteria was performed by conventional methods and biochemical testing. Molecular identification to the species level was performed by 16S rRNA gene sequencing. In total, 12 of 648 samples were positive for Neisseria meningitidis by 16S rRNA sequencing, indicating a prevalence of 1.9%. Isolates were classified into four invasive serogroups (A, B, C, and W) by a comparative sequence analysis of the ribosomal gene. Despite the occurrence of meningococcal disease in Cartagena city in the last several years, the frequency of oropharyngeal carriage in adolescents and young adults was low. Serogroup A had not been previously reported in nasopharyngeal samples in Colombia. This is the first report of Neisseria meningitidis on the Colombian Caribbean coast based on 16S rRNA sequencing and is expected to guide the development of vaccination and follow-up strategies.

D-Mannoside FimH Inhibitors as Non-Antibiotic Alternatives for Uropathogenic Escherichia coli.

FimH is a type I fimbria of uropathogenic Escherichia coli (UPEC), recognized for its ability to adhere and infect epithelial urinary tissue. Due to its role in the virulence of UPEC, several therapeutic strategies have focused on the study of FimH, including vaccines, mannosides, and molecules that inhibit their assembly. This work has focused on the ability of a set of monosubstituted and disubstituted phenyl mannosides to inhibit FimH. To determine the 3D structure of FimH for our in silico studies, we obtained fifteen sequences by PCR amplification of the fimH gene from 102 UPEC isolates. The fimH sequences in BLAST had a high homology (97-100%) to our UPEC fimH sequences. A search for the three-dimensional crystallographic structure of FimH proteins in the PDB server showed that proteins 4X5P and 4XO9 were found in 10 of the 15 isolates, presenting a 67% influx among our UPEC isolates. We focused on these two proteins to study the stability, free energy, and the interactions with different mannoside ligands. We found that the interactions with the residues of aspartic acid (ASP 54) and glutamine (GLN 133) were significant to the binding stability. The ligands assessed demonstrated high binding affinity and stability with the lectin domain of FimH proteins during the molecular dynamic simulations, based on MM-PBSA analysis. Therefore, our results suggest the potential utility of phenyl mannoside derivatives as FimH inhibitors to mitigate urinary tract infections produced by UPEC; thus, decreasing colonization, disease burden, and the costs of medical care.

Franconibacter sp., 1MS: A New Strain in Decolorization and Degradation of Azo Dyes Ponceau S Red and Methyl Orange.

The aim of the present study is focused on the decolorization and degradation of azo dyes Ponceau S Red and Methyl Orange by a bacterial strain isolated from the gold mining district of San Martin de Loba, South of Bolivar (Colombia) sediment samples and identified as Franconibacter sp. 1MS (GenBank: MT568543) based on phenotypic and genotypic methods. A higher percentage of decolorization at 100 mg/L concentration, 37 °C, and pH 7 was recorded at 120 h of incubation period for both dyes. The UV-vis, Fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry analysis of the original dyes and their degraded metabolites confirmed that the decolorization was due to degradation. The proposed metabolic pathways for biodegradation of both dyes have been elucidated, which showed the formation of five intermediate metabolites, namely, N,N-dimethylbenzyl-1,4-diamine, sulfonamide, 1,4-diaminobenzene, 2,5-diaminobenzenesulfonic acid, and 1-amino-2-naphthol, which are not only highly toxic but also be able to be converted through metabolic activation into mutagenic, carcinogenic, and/or teratogenic species. The phytotoxicity studies of the original dye and degraded metabolites were tested on Phaseolus vulgaris and divulged that the degraded metabolites have toxic effects. An effective phytostimulation was observed in Ponceau S Red, which could be attributed to its capacity for enrichment of the culture medium with essential nutrients, a favorable environment for the growth of the plant.

Phylogenetic Classification, Biofilm-Forming Capacity, Virulence Factors, and Antimicrobial Resistance in Uropathogenic Escherichia coli (UPEC).

Uropathogenic Escherichia coli (UPEC) is the main cause of urinary tract infections; in recent years, its importance as a pathogen has increased due to the emergence of hypervirulent and multiresistant strains. In this study, 190 urinary isolates of E. coli were assigned into the seven phylogenetic groups A (11.1%), B1 (4.7%), B2 (46.8%), C (5.8%) D (25.3%) F (2.6%), and Clade I (2.1%), and various virulence genes were examined with polymerase chain reaction methods. All isolates had at least one virulence factor of the 9 analyzed fyuA (81.1%), fimH (96.8%), iutA (74.7%), ompT (66.8%), kpsMTII (66.8%), traT (58.9%), PAI (43.6%), PapAH (26.3%), and usp (3.2%). The results showed a direct relationship between the virulence factors and phylogenetic group A and B2. Further, virulence genetic profiles fimH, fyuA, ompT, traT, and kpsMTII correlated with the production of strong biofilm, multidrug resistance, and the production of moderate hemolysin. These results suggest that these strains may become reservoirs of genes that encode virulence factors, which could be transferred horizontally enhancing their genomic background and high possibility of acquiring new genetic information for possible dissemination. This study provides the first description of phylogroups in UPEC in the Colombian Caribbean and the association with virulence factor profile, antimicrobial susceptibility, and their possible role in the epidemiology in Colombia.