{"title":"Aptamer-nanobody based ELASA for specific detection of Acinetobacter baumannii isolates","authors":"Samaneh Rasoulinejad, Seyed Latif Mousavi Gargari","doi":"10.1016/j.jbiotec.2016.05.024","DOIUrl":null,"url":null,"abstract":"<div><p><em>Acinetobacter baumannii</em> has turned into an important threat in nosocomial outbreak infections and multidrug resistance leading to high mortality rates in the 21<!--> <!-->st century. In recent years its mortality has increased by 15% which in part could be due to lack of a rapid and sensitive diagnostic test. In this work we introduced a new detection test for <em>A. baumannii</em><span> with two highly specific aptamer and nanobody molecules. High binding affinity DNA oligonucleotide aptamers toward </span><em>A. baumannii</em> were selected through 12 rounds of whole cell System Evolution of Ligands by EXponential enrichment process (SELEX). The SELEX procedures was monitored by flow cytometry. The dissociation constant and binding efficiency of the selected aptamer Aci49 was 7.547<!--> <!-->±<!--> <!-->1:353<!--> <!-->pM and 47.50%, respectively. A sandwich enzyme linked aptamer sorbent assay (ELASA) was designed with the biotinylated Aci49 aptamer and our previously developed nanobody against biofilm associated protein (Bap). The assay system was optimized with <em>A. baumannii</em> (ATCC 19606) and 47 clinical isolates of <em>A. baumannii</em> were tested. The threshold of detection in sandwich ELASA process was10<sup>3</sup> CFU/ml. The sensitivity of test toward the clinical isolates was 95.47%. Our results reveal that the sandwich ELASA is sensitive and specific enough for the rapid detection of <em>A. baumannii</em> from clinical isolates.</p></div>","PeriodicalId":15153,"journal":{"name":"Journal of biotechnology","volume":null,"pages":null},"PeriodicalIF":4.1000,"publicationDate":"2016-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jbiotec.2016.05.024","citationCount":"41","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of biotechnology","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0168165616302802","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOTECHNOLOGY & APPLIED MICROBIOLOGY","Score":null,"Total":0}
引用次数: 41
Abstract
Acinetobacter baumannii has turned into an important threat in nosocomial outbreak infections and multidrug resistance leading to high mortality rates in the 21 st century. In recent years its mortality has increased by 15% which in part could be due to lack of a rapid and sensitive diagnostic test. In this work we introduced a new detection test for A. baumannii with two highly specific aptamer and nanobody molecules. High binding affinity DNA oligonucleotide aptamers toward A. baumannii were selected through 12 rounds of whole cell System Evolution of Ligands by EXponential enrichment process (SELEX). The SELEX procedures was monitored by flow cytometry. The dissociation constant and binding efficiency of the selected aptamer Aci49 was 7.547 ± 1:353 pM and 47.50%, respectively. A sandwich enzyme linked aptamer sorbent assay (ELASA) was designed with the biotinylated Aci49 aptamer and our previously developed nanobody against biofilm associated protein (Bap). The assay system was optimized with A. baumannii (ATCC 19606) and 47 clinical isolates of A. baumannii were tested. The threshold of detection in sandwich ELASA process was103 CFU/ml. The sensitivity of test toward the clinical isolates was 95.47%. Our results reveal that the sandwich ELASA is sensitive and specific enough for the rapid detection of A. baumannii from clinical isolates.
期刊介绍:
The Journal of Biotechnology has an open access mirror journal, the Journal of Biotechnology: X, sharing the same aims and scope, editorial team, submission system and rigorous peer review.
The Journal provides a medium for the rapid publication of both full-length articles and short communications on novel and innovative aspects of biotechnology. The Journal will accept papers ranging from genetic or molecular biological positions to those covering biochemical, chemical or bioprocess engineering aspects as well as computer application of new software concepts, provided that in each case the material is directly relevant to biotechnological systems. Papers presenting information of a multidisciplinary nature that would not be suitable for publication in a journal devoted to a single discipline, are particularly welcome.