PREVALENCE OF TETRACYCLINE RESISTANCE GENES IN ESCHERICHIA COLI ISOLATED FROM FOOD SAMPLES IN AND AROUND MICHAEL AND CECILIA IBRU UNIVERSITY, NIGERIA
Authors: Aihiokhai Mark Ohioghie , Chika Otunyo Lilian , Imoni Cletus Aikhenobhoria 
Published: September 2023

Background: Genes that confer resistance to tetracycline, a common antibiotic used in both human and veterinary medicine, are among the antibiotic resistance genes of most concern. Tetracycline treatment, a crucial weapon in the fight against bacterial infections, can become ineffective because of this resistance.
Aim: Determination of the prevalence of tetracycline resistance genes within Escherichia coli strains found in food samples obtained from local food vendors in and around Michael and Cecilia Ibru University, Agbarha-Otor.
Methods: Food samples were obtained from 6 out of 10 selected food vendors in and around MCIU campus. A total sample size of 100 respondents were administered questionnaires. Out of a total food sample size of 28, about 25grams of food samples were homogenized with 225 ml of buffered peptone water (BPW) in an electric blender (Vitamix 5200 model). Eosin Methylene Blue (EMB) agar was subsequently used as the culture media. About 0.5 ml aliquots of the inoculum were taken to extract DNA by the modified Boiling Lysis Method. Polymerase Chain Reaction (PCR) was performed using a thermocycler for the detection of tetA gene in E. coli isolates using specific primers (tetA-F CGCCTTTCCTTTGGGTTCTCTATATC; tetA-R CAGCCCACCGAGCAC AGG; Size=182 base pairs). Thereafter, gel electrophoresis was done at 200 volts for 15 minutes and studied under UV light Gel Documentation System (Cleaver Scientific, UK). Statistical analysis was conducted using Chi-square tests to identify significant differences (p<0.05) in resistance patterns among the food categories.
Results: Tetracycline resistant gene (tetA) was investigated among 18 of 28 cultured samples which had E. coli growth indicating 64% prevalence. Electrophoresis results indicated the presence of tetA gene in 11 out of the 18 E. coli positive samples as the prevalence of tetA gene was 61%. Lane 2, 4, 5, 6, 7, and 10 showed bands at 182 bp confirming the isolate contained tetA gene. Lane 5 showed additional bands at 780 bp which indicated possible superficial polymorphism of the tetA gene in isolates. The presence of bands at 182 bp confirmed the presence of the gene, and the presence of additional bands at 780 bp in Lane 5 suggested potential genetic variation in the tetA gene.
Conclusion: The study contributes to a broader understanding of antibiotic resistance patterns, gene prevalence, and genetic variations in bacterial isolates, with particular reference to E. coli. It underscores the need for continued surveillance and research into antimicrobial resistance, particularly in environments where E. coli contamination is of concern, such as food vendor settings.

Peer Review History:
Received: 20 June 2023; Revised: 14 July; Accepted: 27 August, Available online: 15 September 2023
Academic Editor: Dr. A.A. Mgbahurike, University of Port Harcourt, Nigeria, amaka_mgbahurike@yahoo.com
Received file: Reviewer's Comments:
Average Peer review marks at initial stage: 6.0/10
Average Peer review marks at publication stage: 7.0/10
Reviewers:
Prof. Hassan A.H. Al-Shamahy, Sana'a University, Yemen, shmahe@yemen.net.ye
Dr. Bilge Ahsen KARA, Ankara Gazi Mustafa Kemal Hospital, Turkey, ahsndkyc@gmail.com