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Cryptococcus neoformans species complexes are recognized as environmental fungi responsible for lethal meningoencephalitis in immunocompromised individuals. Despite the vast knowledge about the epidemiology and genetic diversity of this fungus in different regions of the world, more studies are necessary to comprehend the genomic profiles across South America, including Colombia, considered to be the second country with the highest number of Cryptococcosis. Here, we sequenced and analyzed the genomic architecture of 29 Colombian C. neoformans isolates and evaluated the phylogenetic relationship of these strains with publicly available C. neoformans genomes. The phylogenomic analysis showed that 97% of the isolates belonged to the VNI molecular type and the presence of sub-lineages and sub-clades. We evidenced a karyotype without changes, a low number of genes with copy number variations, and a moderate number of single-nucleotide polymorphisms (SNPs). Additionally, a difference in the number of SNPs between the sub-lineages/sub-clades was observed; some were involved in crucial fungi biological processes. Our study demonstrated the intraspecific divergence of C. neoformans in Colombia. These findings provide evidence that Colombian C. neoformans isolates do not probably require significant structural changes as adaptation mechanisms to the host. To the best of our knowledge, this is the first study to report the whole genome sequence of Colombian C. neoformans isolates. [ABSTRACT FROM AUTHOR]

Background: Cryptococcus neoformans is an opportunistic fungal pathogen that can cause meningitis in immunocompromised individuals. The objective of this work was to study the relationship between the phenotypes and genotypes of isolates of clinical origin from different cities in Colombia. Methods: Genome classification of 29 clinical isolates of C. neoformans var. grubii was performed using multilocus sequence typing (MLST), and genomic sequencing was used to genotype protein-coding genes. Pathogenicity was assessed in a larval model, and melanin production and capsule size were evaluated in vitro and in vivo. Results: Eleven MLST sequence types (STs) were found, the most frequent being ST69 (n = 9), ST2, ST93, and ST377 (each with n = 4). In the 29 isolates, different levels of pigmentation, capsule size and pathogenicity were observed. Isolates classified as highly pathogenic showed a tendency to exhibit larger increases in capsule size. In the analysis of polymorphisms, 48 non-synonymous variants located in the predicted functional domains of 39 genes were found to be associated with capsule size change, melanin, or pathogenicity. Conclusions: No clear patterns were found in the analysis of the phenotype and genotype of Cryptococcus. However, the data suggest that the increase in capsule size is a key variable for the differentiation of pathogenic isolates, regardless of the method used for its induction. [ABSTRACT FROM AUTHOR]

Introduction: In Colombia, Shigella sonnei is one of the most frequently isolated serotypes (53.4%) in human clinical samples associated with diarrheal acute disease. The identification of DNA restriction patterns by pulsed field gel electrophoresis is the basis for the molecular surveillance of S. sonnei ., Objective: To establish the basis for the molecular surveillance of S. sonnei in Colombia using pulsed-field gel electrophoresis., Materials and Methods: We studied 102 of 2,048 S. sonnei isolates referred by the National Laboratory Network between 1997 and March, 2013; the selection was made according to the antimicrobial multiresistance profile, the source of samples, and the relation to outbreaks. The genetic profile was determined by pulsed field gel electrophoresis using the restriction enzymes XbaI and BlnI in accordance with the PulseNet International protocol. The electrophoretic patterns were analyzed with the GelCompare II, version 4.0 software., Results: We obtained 42 electrophoretic patterns with a 70% to 100% similarity. The most frequent pattern was COIN08J16X01.0017 with 17.6%, followed by patterns COIN04J16X01.0004 with 9.8%, and COIN02J16X01.0002 with 5.8%, while the remaining 66.8% was associated with other electrophoretic patterns. The analysis of 10 outbreaks demonstrated their genetic relation with a 100% of similarity; the most frequent pattern in outbreaks was COIN08J16X01.0017 with 17.1%., Conclusion: The genotypic database for Shigella sonnei isolates was established using pulsed field gel electrophoresis including the 42 unique patterns identified in this study.