Rapid, specific and sensitive electrochemical detection of foodborne bacteria

• Published in: Biosensors & bioelectronics Vol. 24; no. 9; pp. 2766 - 2771
• Main Authors: Pöhlmann, Christopher, Wang, Yiran, Humenik, Martin, Heidenreich, Bernd, Gareis, Manfred, Sprinzl, Mathias
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.05.2009; Elsevier
• Subjects: Alicyclobacillus acidocaldarius; Bacillus - enzymology; Bacillus - genetics; Bacterial Proteins - chemical synthesis; Bacterial Proteins - metabolism; Base Sequence; Biological and medical sciences; Biosensing Techniques - economics; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensors; Biotechnology; Electrochemical biosensor; Electrochemical Techniques - economics; Electrochemical Techniques - instrumentation; Electrochemical Techniques - methods; Escherichia coli; Esterase; Esterases - chemical synthesis; Esterases - metabolism; Foodborne bacteria; Fundamental and applied biological sciences. Psychology; Gram-Negative Bacteria - enzymology; Gram-Negative Bacteria - genetics; Gram-Positive Bacteria - enzymology; Gram-Positive Bacteria - genetics; Meat - analysis; Meat - microbiology; Methods. Procedures. Technologies; Molecular Sequence Data; Nucleic Acid Hybridization - methods; Oligodeoxyribonucleotides - chemical synthesis; Oligodeoxyribonucleotides - genetics; RNA, Bacterial - analysis; RNA, Bacterial - genetics; RNA, Bacterial - isolation & purification; RNA, Ribosomal, 16S - analysis; RNA, Ribosomal, 16S - genetics; RNA, Ribosomal, 16S - isolation & purification; Sensitivity and Specificity; Time Factors; Various methods and equipments; Esterase; Electrochemical biosensor; Foodborne bacteria; Enzyme; Biosensor; Electrochemistry; Hydrolases; Bacteria; Esterases; Detection
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2009.01.042

Electrochemical biochips are an emerging tool for point-of-care diagnostic systems in medicine, food and environmental monitoring. In the current study, a thermostable reporter enzyme, esterase 2 (EST2) from Alicyclobacillus acidocaldarius, is used for specific and sensitive detection of bacteria by one-step rRNA/DNA hybridization between a bacterium-specific capture oligodeoxynucleotide (ODN), bacterial 16S rRNA and an uniform EST2–ODN reporter conjugate. The detection limit corresponds to approximately 500 colony forming units (cfu) Escherichia coli. Beside high sensitivity, the application of electrochemical biochips allows discrimination of two Gram-negative and two Gram-positive bacteria demonstrating the specificity and the potential for parallel detection of microorganisms. The feasibility of identification of foodborne bacteria was studied with meat juice contaminated with E. coli. This detection system has the capability to be applied for monitoring of bacterial food contamination.