Characterization of Class 1 integrons and some antimicrobial resistance genes in Salmonella species isolated from poultry in Egypt

Abstract

Salmonella enterica includes serotypes that were implicated as a food borne pathogens crucially affecting public health and the economic organization. This study was directed to isolate and identify of Salmonella strains from 222 different species and ages of poultry (broiler, chick, ducks, pigeon, quails) from Kafr El Sheikh governorate. The Salmonella isolation rate was (4.5%) as (0.9%) from apparently healthy, (3.6%) from diseased birds. The outer membrane protein F gene was used as promising tool for detection of Genus Salmonella, after that four isolates were identified serologically as two Salmonella enterica serovar Enteritidis and two Salmonella enterica serovar Typhimurium. The resistance pattern of positive Salmonella isolates showed multidrug resistance phenotypes and qnrS for quinolone resistant genes was recorded in one isolate while blaTEM for β-lactam resistant isolates, aacC for aminoglycosides were recorded in all four Salmonella isolates using PCR technique. Also, Class 1 integrons detected with a percentage of (100%) in examined isolates. Sequencing of the class 1 integrons cassettes showed genes encoding resistance specified to streptothricin acetyltransferase (sat) gene, aminoglycoside acetyltransferase (aac3-Id) and aminoglycoside adenyltransferase (aadA7). Class 1 integrons harbored gene encoding domains unfunction protein (duf) in one S. enterica serovar Typhimurium isolate. This study spotlights the significant role of the drug-resistance genes and Class 1 integrons in Salmonella as zoonotically important pathogens of public health importance.