Identification and antibiotics resistance profile of gram-negative bacteria isolated from sediment Anil river in Maranhão, Brazil

The Manguezal ecosystem suffers impacts from human anthropic actions, which can cause transformations in the microbiota and selection of antibiotic-resistant variants. Thus, this study aimed to isolate and identify gram-negative bacteria to characterize the resistance genes to b-lactam antibiotics from sediment samples from the Anil River – MA (Manguezais area). The bacterial isolate was obtained from sediment samples plated on Macconkey Agar supplemented with antibiotics ceftazidime and meropenem. MALDI-QTOF identified the isolated bacterial species. The bacterial isolates were subjected to the Kirby-Bauer method to evaluate the antibiotic susceptibility profile. The PCR technique detected the genetic determinants. This study identified three and two bacteria; 20 isolates were classified as Ochrobactrum intermedium, 09 Ochrobactrum tritici, 02 Stenotrophomonas maltophilia, and 01 Klebsiella pneumoniae. In antibiotic susceptibility tests, it was observed that 100% (n=32) of the isolates were resistant to cefepime, 96.8% (n=31) to ofloxacin and ceftriaxone, and 90.6% (n=29) to imipenem. The molecular profile showed that 50% (n=16) presented the blaGES gene. In addition, genes belonging to the blaOXA profile were identified in 21 bacteria isolates from the genus Ochrobactrum, with the blaOXA1 gene being the most prevalent among the isolates, identified in 11 bacterial lines. This study confirms that environments such as mangroves, which act as reservoirs of bacteria resistant to multiple antimicrobial drugs for clinical use, become a risk to human health.