| Congresso Brasileiro de Microbiologia 2023 | Resumo: 870-1 | ||||
Resumo:Staphylococcus nepalensis is a coagulase-negative Staphylococcus (CoNS) that was initially identified as a part of the normal microbiota of goats. However, it is now known to be found in different locations and hosts, including in some cases of opportunistic infections in humans. Similar to other CoNS, S. nepalensis may be a reservoir of antimicrobial resistance (AMR) to more pathogenic species, such as S. aureus. Therefore, understanding evolutionary processes, such as recombination and horizontal gene transfer (HGT), is fundamental to the surveillance and control of infections caused by Staphylococcus species. To better characterize S. nepalensis plasmids, we evaluated different protocols for DNA plasmid extraction. We investigated whether the choice of the DNA extraction method, specifically a genomic DNA extraction protocol (Method 1) or a plasmid-directed DNA extraction protocol (Method 2), affected plasmid sequence reconstruction. Both DNA samples were sequenced on the Illumina MiSeq platform (BPI). Pre-processed reads were subjected to de novo assembly using SPAdes, and plasmid contigs were separated by PlasmidSPades. The plasmid scaffolds obtained from both samples were compared to all plasmids available in GenBank. For plasmid analysis, we utilized Progressive Mauve for multiple alignments and ResFinder to search for acquired antimicrobial resistance genes. The results of PlasmidSpades using the sequencing data from Method 1 revealed that 40% of the predicted plasmid contigs were false positives, whereas none were observed for the Method 2. Among three possible plasmids recovered from Method 2, the smallest one (4524 bp) encoded resistance to streptomycin and displayed 99.92% identity and 100% query coverage to S. aureus strain USA300-SUR11 plasmid pUSA06-1-SUR11 and Macrococcus caseolyticus strain JCSC5402 plasmid, and 95.63% identity and 74% query coverage to Mammaliicoccus lentus strain 7074 plasmid pML7074-1. Another plasmid (14815 pb) exhibited 98.45% identity and 60% query coverage to S. aureus strain PCFH-226 plasmid pP541 and 99.11% identity and 56% query coverage to S. equorum strain PU1 plasmid plas1. With the third plasmid, we found a S. cohnii strain FDAARGOS_744 plasmid unnamed4 with 93.76% identity and 48% query coverage and a Staphylococcus sp. strain AntiMn-1 plasmid with 85.12% identity and 62% query coverage. ResFinder detected in both samples genes encoding resistance to aminoglycoside (str), beta lactam (blaZ), chloramphenicol (cat), and tetracycline (tetK). Our findings indicate that the use of a plasmid extraction method for sequencing facilitates plasmid assembly and suggest that plasmids can move not only between Staphylococcus species but also among closely related genera such as Macrococcus and Mammaliicoccus. Palavras-chave: ANTIMICROBIAL RESISTANCE, PLASMID , SEQUENCING , S. nepalensis Agência de fomento:CAPES, CNPq, FAPERJ | |||||