Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus

Background/Purpose: Among DNA-based techniques, polymerase chain reaction (PCR) is the most widely accepted molecular tool for the detection of pathogens. However, the technique involves several reagents and multiple pipetting steps that often lead to error-prone results. Additionally, the reagents...

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Main Authors: Sowmya Nagaraj, Shylaja Ramlal, Joseph Kingston, Harsh Vardhan Batra
Format: Article
Language:English
Published: Elsevier 2018-04-01
Series:Journal of Microbiology, Immunology and Infection
Online Access:http://www.sciencedirect.com/science/article/pii/S1684118216300330
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author Sowmya Nagaraj
Shylaja Ramlal
Joseph Kingston
Harsh Vardhan Batra
author_facet Sowmya Nagaraj
Shylaja Ramlal
Joseph Kingston
Harsh Vardhan Batra
author_sort Sowmya Nagaraj
collection DOAJ
description Background/Purpose: Among DNA-based techniques, polymerase chain reaction (PCR) is the most widely accepted molecular tool for the detection of pathogens. However, the technique involves several reagents and multiple pipetting steps that often lead to error-prone results. Additionally, the reagents entail a cold-chain facility to maintain their stability during storage and transportation. The main aim of the present study was to simplify the utility of a pre-optimized multiplex PCR format that was developed to detect toxigenic strains of Staphylococcus aureus by providing stable, pre-mixed, and ready-to-use master mix in a lyophilized formulation. Methods: Master mix containing all reagents except the template was lyophilized in the presence of an excipient lyoprotectant to achieve long-term stability without altering the sensitivity, specificity and PCR performance. Bromophenol blue was also included in the master mix to reduce the risk of external contamination during gel loading. The stability of lyophilized master mix was analyzed at different temperatures. The PCR performance was also examined after exposure of master mix to notable temperature fluctuations during transportation. Results: The shelf-life of lyophilized master mix was estimated to be 1.5 months at ambient temperature and 6 months at 4°C. Stability was unaffected by temperature fluctuations during transportation even in cold-chain-free conditions, thus reducing the cost required for cold storage. Conclusion: The sensitive, cost-effective, ready-to-use, and ambient temperature stable formulation could be implemented as a detection tool in food analysis and diagnostic laboratories and hospitals and for on-field application outside the laboratories, as well as for detection of toxigenic strains of S. aureus. Keywords: Bromophenol blue, Cold-chain-free, Lyoprotectant, Multiplex polymerase chain reaction, Stabilization, Staphylococcus aureus
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spelling doaj.art-f0e52dde9e124000bea83dd7ce5a4fa72022-12-21T20:11:44ZengElsevierJournal of Microbiology, Immunology and Infection1684-11822018-04-01512191198Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureusSowmya Nagaraj0Shylaja Ramlal1Joseph Kingston2Harsh Vardhan Batra3Microbiology Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, IndiaCorresponding author. Microbiology Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, 570011, India.; Microbiology Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, IndiaMicrobiology Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, IndiaMicrobiology Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, IndiaBackground/Purpose: Among DNA-based techniques, polymerase chain reaction (PCR) is the most widely accepted molecular tool for the detection of pathogens. However, the technique involves several reagents and multiple pipetting steps that often lead to error-prone results. Additionally, the reagents entail a cold-chain facility to maintain their stability during storage and transportation. The main aim of the present study was to simplify the utility of a pre-optimized multiplex PCR format that was developed to detect toxigenic strains of Staphylococcus aureus by providing stable, pre-mixed, and ready-to-use master mix in a lyophilized formulation. Methods: Master mix containing all reagents except the template was lyophilized in the presence of an excipient lyoprotectant to achieve long-term stability without altering the sensitivity, specificity and PCR performance. Bromophenol blue was also included in the master mix to reduce the risk of external contamination during gel loading. The stability of lyophilized master mix was analyzed at different temperatures. The PCR performance was also examined after exposure of master mix to notable temperature fluctuations during transportation. Results: The shelf-life of lyophilized master mix was estimated to be 1.5 months at ambient temperature and 6 months at 4°C. Stability was unaffected by temperature fluctuations during transportation even in cold-chain-free conditions, thus reducing the cost required for cold storage. Conclusion: The sensitive, cost-effective, ready-to-use, and ambient temperature stable formulation could be implemented as a detection tool in food analysis and diagnostic laboratories and hospitals and for on-field application outside the laboratories, as well as for detection of toxigenic strains of S. aureus. Keywords: Bromophenol blue, Cold-chain-free, Lyoprotectant, Multiplex polymerase chain reaction, Stabilization, Staphylococcus aureushttp://www.sciencedirect.com/science/article/pii/S1684118216300330
spellingShingle Sowmya Nagaraj
Shylaja Ramlal
Joseph Kingston
Harsh Vardhan Batra
Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus
Journal of Microbiology, Immunology and Infection
title Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus
title_full Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus
title_fullStr Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus
title_full_unstemmed Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus
title_short Thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic Staphylococcus aureus
title_sort thermostabilization of indigenous multiplex polymerase chain reaction reagents for detection of enterotoxigenic staphylococcus aureus
url http://www.sciencedirect.com/science/article/pii/S1684118216300330
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AT josephkingston thermostabilizationofindigenousmultiplexpolymerasechainreactionreagentsfordetectionofenterotoxigenicstaphylococcusaureus
AT harshvardhanbatra thermostabilizationofindigenousmultiplexpolymerasechainreactionreagentsfordetectionofenterotoxigenicstaphylococcusaureus