Antibiotic resistance profile and occurrence of AmpC between Pseudomonas aeruginosa isolated from a domestic full-scale WWTP in southeast Brazil

Abstract

Wastewater treatment plants (WWTPs) represent an important reservoir of antibiotic resistance determinants. Although many studies have been conducted to evaluate resistance profiles in Enterobacteriaceae isolates from this setting, the dynamics of this phenomenon are poorly known to the bacterium Pseudomonas aeruginosa. Here we aimed to evaluate the resistance profiles and the production of AmpC β-lactamase in P. aeruginosa isolates from a domestic full-scale WWTP. Samples of the raw sewage and effluent were collected and the bacterium P. aeruginosa was isolated on cetrimide agar. Susceptibility to β-lactams, fluoroquinolones and aminoglycosides was evaluated by the disc diffusion method, and the presence of AmpC β-lactamase was investigated phenotypically and by molecular method. We recovered 27 isolates of P. aeruginosa. Of these, 81.5% were susceptible to all antimicrobials tested. However, a considerable rate of resistance to carbapenems (11%) was found among the isolates. Twenty-two isolates were positive in the phenotypic test for inducible AmpC β-lactamase but the bla gene was only identified in four isolates, suggesting the presence of other independent resistance mechanisms besides this β-lactamase. In summary, we have shown that P. aeruginosa isolates from a domestic WWTP represents a potential reservoir of bla genes and other resistance determinants, including those that result in low susceptibility to carbapenems and aminoglycosides.

β-lactamases (bla TEM, bla SHV, bla CTXM-1, bla VEB, bla OXA-1) and class C β-lactamases gene frequency in Pseudomonas aeruginosa isolated from various clinical specimens in Khartoum State, Sudan: a cross sectional study

“…In P. aeruginosa over expressed AmpC β-lactamase mediate the resistance to broad spectrum cephalosporins 3 . AmpC β-lactamase in P. aeruginosa has also been reported in different countries around the world [20][21][22][23][24][25][26][27] .…”

Anthropogenic Activities and the Problem of Antibiotic Resistance in Latin America: A Water Issue

“…Resistance to several antibiotics (ESBL, 3rd generation cepholosporins, tetracyclines, quinolones and carbapenems) were reported by Picão et al, 2013 [60]. Wastewaters were studied intensely in South America [50,55,57,72]. Irrigation water has also been linked to the dissemination of AMR [82,84].…”

Aspergillus niger Culture Filtrate (ACF) Mediated Biocontrol of Enteric Pathogens in Wastewater

“…Sample incubated with sterile water served as control. The selective media used for the study were HiCrome Klebsiella Selective Agar (HiMedia, Mumbai, India) for isolation of Klebsiella, SS agar-Salmonella Shigella agar for enumeration of Salmonella and Shigella, EMB agar-Eosin Methylene blue agar for E. coli [44], TCBS -Thiosulfate citrate bile salts sucrose agar for Vibrio [45], MSA-Mannitol Salt agar for Staphylococcus [46] and Cetrimide agar for Pseudomonas [47]. The effects of neutralised (N) ACF, heat-inactivated (H), and neutralised heat-inactivated (N+H) ACF on wastewater were also investigated to understand the antimicrobial nature of ACF.…”