title: Rapid detection of methicillin-resistant Staphylococcus aureus in pork using a nucleic acid-based lateral flow immunoassay.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) is considered as one of the leading causes of food poisonings worldwide. Due to the high prevalence and extensive challenges in clinical treatment, a rapid and accurate detection method is required to differentiate MRSA from other S. aureus isolated from foods. Since the methicillin resistance of S. aureus is due to the acquisition of the mecA gene from staphylococcal chromosome cassette, the presence of the mecA gene is interpreted as a marker for the identification of MRSA. In this study, a low-cost lateral flow immunoassay (LFI) strip was used to detect the mecA amplicons subsequent to polymerase chain reaction (PCR). The specificity of this PCR-LFI assay was tested between MRSA and methicillin-susceptive S. aureus. Both the test line and control line were shown up on the LFI strip for MRSA, whereas only the control line developed for methicillin-susceptive S. aureus. The detection limit of PCR-LFI assay was 20fg for genomic DNA (100 times more sensitive than gel electrophoresis) and 2×100CFU per 100g of pork products after enrichment at 37°C for 48h. The total detection time of using LFI was 3min, which was faster than the conventional electrophoresis (~45min). With the performance of PCR-LFI, 7 out of 42 S. aureus isolates were identified to be MRSA from imported pork products, which was consistent to the standardized minimum inhibitory concentration assay. This mecA-based PCR-LFI strip can be used for rapid and accurate detection of MRSA isolated from commercial pork products.
authors.affiliation: Key Laboratory of Food Nutrition, Safety Ministry of Education of China, Tianjin University of Science and Technology, Tianjin 300457, China; Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Luyao
authors.initials: L
authors.lastname: Ma
authors.affiliation: Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Lina
authors.initials: L
authors.lastname: Ma
authors.affiliation: Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Marti Z
authors.initials: MZ
authors.lastname: Hua
authors.affiliation: Key Laboratory of Food Nutrition, Safety Ministry of Education of China, Tianjin University of Science and Technology, Tianjin 300457, China. Electronic address: s.wang@tust.edu.cn.
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.affiliation: Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Electronic address: xiaonan.lu@ubc.ca.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Lu
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D059022:Food Safety / Q000379:methods; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008712:Methicillin / Q000494:pharmacology; D016106:Methicillin Resistance / Q000235:genetics*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000235:genetics; D008826:Microbial Sensitivity Tests; D046915:Penicillin-Binding Proteins / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D000069466:Red Meat / Q000382:microbiology*; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000188:drug therapy; D013552:Swine / Q000382:microbiology
chemical_list: D001426:Bacterial Proteins; D046915:Penicillin-Binding Proteins; C487789:mecA protein, Staphylococcus aureus; D008712:Methicillin
keywords: Food safety; Lateral flow immunoassay; MRSA; PCR; mecA