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High-throughput Detection of Respiratory Pathogens in Animal Specimens by Nanoscale PCR
Published on: November 28, 2016
A colorimetric amplification-based method for identification of Moraxella catarrhalis, a human respiratory tract
Kiana Gholizad Monavari1, Hamidreza Mollasalehi1
1Department of Microbiology and Microbial Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, 1983969411, Iran.
Abstract:
Moraxella catarrhalis is a significant pathogen associated with both upper and lower respiratory tract infections. This study aims to identify M. catarrhalis using the ompCD gene, which encodes a major outer membrane protein. Spectrophotometry was used to evaluate the accuracy of the colorimetric method by measuring the A450/A570. The colorimetric measurements and PCR method specificity were assessed utilizing twenty bacterial samples. The results of M. catarrhalis detection confirmed the presence of a specific band at 273 base pairs and a light red color, with an A450/A570 ratio of 1.5. However, 100% specificity was observed in negative samples with an A450/A570 ratio of 1.15 or less, lacking an amplicon band and showing a deep red color. Furthermore, the selectivity of the techniques was confirmed. The methods revealed a detection limit of 0.05 ng/μL. The colorimetric PCR approach is a suitable point-of-care test for rapidly and accurately identifying M. catarrhalis.
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