RESUMO
BACKGROUND: Paipa cheese is a traditional, semi-ripened cheese made from raw cow's milk in Colombia. The aim of this work was to gain insights on the microbiota of Paipa cheese by using a culture-independent approach. METHOD: two batches of Paipa cheese from three formal producers were sampled during ripening for 28 days. Total DNA from the cheese samples was used to obtain 16S rRNA gene sequences by using Illumina technology. RESULTS: Firmicutes was the main phylum found in the cheeses (relative abundances: 59.2-82.0%), followed by Proteobacteria, Actinobacteria and Bacteroidetes. Lactococcus was the main genus, but other lactic acid bacteria (Enterococcus, Leuconostoc and Streptococcus) were also detected. Stapylococcus was also relevant in some cheese samples. The most important Proteobacteria were Enterobacteriaceae, Aeromonadaceae and Moraxellaceae. Enterobacter and Enterobacteriaceae (others) were detected in all cheese samples. Serratia and Citrobacter were detected in some samples. Aeromonas and Acinetobacter were also relevant. Other minor genera detected were Marinomonas, Corynebacterium 1 and Chryseobacterium. The principal coordinates analysis suggested that there were producer-dependent differences in the microbiota of Paipa cheeses. CONCLUSIONS: lactic acid bacteria are the main bacterial group in Paipa cheeses. However, other bacterial groups, including spoilage bacteria, potentially toxin producers, and bacteria potentially pathogenic to humans and/or prone to carry antimicrobial resistance genes are also relevant in the cheeses.
RESUMO
Se efectuó un estudio con el empleo de la metodología de Gupta, en el Departamento de Biología y Geografía de la Universidad de Oriente en Santiago de Cuba, para determinar marcadores moleculares de tipo inserción en secuencias de las proteínas ADN polimerasa I y ADN polimerasa III (subunidad alfa), obtenidas de bases de datos internacionales y posteriormente alineadas con el programa ClustalX2. Las familias Moraxellaceae y Helicobacteraceae han sido ampliamente estudiadas, porque comprenden agentes patógenos causantes de numerosas enfermedades en humanos, pero pocas investigaciones han estado dirigidas a la identificación de las características moleculares que puedan distinguir a sus miembros de otros grupos de bacterias; de manera que los presentes resultados constituyen un aporte al conocimiento de la genética y la bioquímica de estas familias y proveen herramientas moleculares para la clasificación taxonómica y el diagnóstico de especies patógenas
A study with the use of Gupta methodology was carried out in the Biology and Geography Department of Oriente University in Santiago de Cuba, to determine molecular markers of insertion type in sequences of the DNA polimerase I proteins and DNA polimerase III (alpha subunity), obtained from international databases and later on aligned with the ClustalX2 program. The Moraxellaceae and Helicobacteraceae families have been broadly studied, because they comprise pathogen agents that cause numerous diseases in humans, but few investigations have been directed to the identification of the molecular characteristics that can distinguish their members from other groups of bacterias; so these results constitute a contribution to the knowledge of genetics and biochemistry of these families and provide molecular tools for the taxonomic classification and the diagnosis of pathogen species