Occurrence, Phenotypic and Molecular Characterization of Extended-Spectrum- and AmpC- β-Lactamase Producing Enterobacteriaceae Isolated From Selected Commercial Spinach Supply Chains in South Africa

Abstract

The increasing occurrence of multidrug-resistant (MDR) extended-spectrum β-lactamase-(ESBL) and/or AmpC β-lactamase-producing Enterobacteriaceae in health care systems, the environment and fresh produce is a serious concern globally. Production practices, processing and subsequent consumption of contaminated raw fruit and vegetables represent a possible human transmission route. The purpose of this study was to determine the presence of ESBL/AmpC-producing Enterobacteriaceae in complete spinach supply chains and to characterize the isolated strains phenotypically (antimicrobial resistance profiles) and genotypically (ESBL/AmpC genetic determinants, detection of class 1, 2, and 3 integrons). Water, soil, fresh produce, and contact surface samples (n = 288) from two commercial spinach production systems were screened for ESBL/AmpC-producing Enterobacteriaceae. In total, 14.58% (42/288) of the samples were found to be contaminated after selective enrichment, plating onto chromogenic media and matrix-assisted laser desorption ionization time-of-flight mass spectrometry identity confirmation of presumptive ESBL/AmpC isolates. This included 15.28% (11/72) water and 12.12% (16/132) harvested-and processed spinach, while 25% (15/60) retail spinach samples were found to be contaminated with an increase in isolate abundance and diversity in both scenarios. Dominant species identified included Serratia fonticola (45.86%), Escherichia coli (20.83%), and Klebsiella pneumoniae (18.75%). In total, 48 (81.36%) isolates were phenotypically confirmed as ESBL/AmpC-producing Enterobacteriaceae of which 98% showed a MDR phenotype. Genotypic characterization (PCR of ESBL/AmpC resistance genes and integrons) further revealed the domination of the CTX-M Group 1 ESBL type, followed by TEM and SHV; whilst the CIT-type was the only plasmid-mediated AmpC genetic determinant detected. Integrons were detected in 79.17% (n = 38) of the confirmed

Extended Spectrum Beta-Lactamase-Resistant Determinants among Carbapenem-Resistant Enterobacteriaceae from Beef Cattle in the North West Province, South Africa: A Critical Assessment of Their Possible Public Health Implications

“…The blaSHV , blaTEM and blaCTX-M were the most frequently (20.5–33.1%) detected genes. However, these findings were lower than those of the previous studies, which reported the prevalence of ESBL-producing strains obtained from hospital environment [ 27 , 44 , 45 ]. The variation could be attributed to the source of samples, geographical location and the number of isolates analysed per study.…”

Antimicrobial resistance profiles and genetic basis of resistance among non-fastidious Gram-negative bacteria recovered from ready-to-eat foods in Kibera informal housing in Nairobi, Kenya

“…coli and K. pneumoniae isolates from spinach samples [46]. These β-lactams genes code for antimicrobial resistance enzymes that have been associated with resistances in diverse β-lactam antibiotics such as ampicillin, ceftriaxone, cefotaxime and ceftazidime [14].…”

“…If these integrons are contained in mobile plasmids, these resistance genes can be spread between and across species, consequently worsening AMR’s menace. A study in South Africa has also reported carriage of bla CTX-M , bla TEM , bla SHV , bla OXA and intI 1 in E. coli and K. pneumoniae isolates from spinach samples [ 46 ]. These β-lactams genes code for antimicrobial resistance enzymes that have been associated with resistances in diverse β-lactam antibiotics such as ampicillin, ceftriaxone, cefotaxime and ceftazidime [ 14 ].…”

Advanced molecular characterization of enteropathogenic Escherichia coli isolated from diarrheic camel neonates in Egypt

“…MphA is responsible for production of macrolide 2′-phosphotransferase I that inactivates 14-ring macrolides, such as erythromycin and oleandomycin [12]. Another drug resistance gene, AmpC, encodes AmpC β-lactamase that degrades penicillins [13]. aadB is responsible for the production of 2'-aminoglycoside nucleotidyltransferase enzyme that inactivates aminoglycoside antibiotics [14].…”