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Pseudomonas aeruginosa owns a variability of virulence factors. These factors can increase bacterial pathogenicity and infection severity. Despite the importance of knowledge about them, these factors are not more characterized at level of strains derived from local food products. This study aimed to characterize the virulence potential of P. aeruginosa isolated from various animal products. Several structural and virulence genes of P. aeruginosa including lasB, exoS, algD, plcH, pilB, exoU, and nan1 were detected by polymerase chain reaction (PCR) on 204 strains of P. aeruginosa. They were isolated from bovine meat (122), fresh fish (49), and smoked fish (33). The 16S rRNA gene was detected on 91.1% of the presumptive strains as Pseudomonas. The rpoB gene showed that 99.5% of the strains were P. aeruginosa. The lasB gene (89.2%) was the most frequently detected (p < 0.05). In decreasing importance order, exoS (86.8%), algD (72.1%), plcH (72.1%), pilB (40.2%), and exoU (2.5%) were detected. The lasB gene was detected in all strains of P. aeruginosa serogroups O11 and O16. The prevalence of algD, exoS, and exoU genes in these strains varied from 51.2% to 87.4%. The simultaneous determination of serogroups and virulence factors is of interest for the efficacy of surveillance of infections associated with P. aeruginosa.

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This study investigated the diversity and dynamics of yeasts involved in alcoholic fermentation of a traditional sorghum beer from Côte d'Ivoire, tchapalo. A total of 240 yeast strains were isolated from fermenting sorghum wort inoculated with dry yeast from two geographic regions of Côte d'Ivoire (Abidjan and Bondoukou). Initial molecular identification to the species level was carried out using RFLP of PCR-amplified internal transcribed spacers of rDNA (ITS1-5.8S-ITS2). Ten different profiles were obtained from the restriction of PCR products with the three endonucleases HaeIII, CfoI and HinfI. Sequence analysis of the D1/D2 domain of the 26S rDNA and the ACT1 gene allowed us to assign these groups to six different species: Saccharomyces cerevisiae-like, Candida tropicalis, Pichia kudriavzevii, Pichia kluyveri, Kodamaea ohmeri and Meyerozyma caribbica. The most frequent species associated with tchapalo fermentation was S. cerevisiae-like (87.36%), followed by C. tropicalis (5.45%) and M. caribbica (2.71%). S. cerevisiae-like strains were diploid heterozygotes and exhibited three to four nucleotides divergence from the type strain in the D1/D2 domain and several indels in the more discriminant sequence of the intron of the ACT1 gene. During the process, the yeast species isolated and their frequencies varied according to the geographic origin of the dry yeast. The occurrence of some species was sporadic and only two non-Saccharomyces species were found in the final product.

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