A System to Simultaneously Detect Tick-borne Pathogens Based on the Variability of the 16S Ribosomal Genes
Overview
Tropical Medicine
Affiliations
Background: DNA microarrays can be used to quickly and sensitively identify several different pathogens in one step. Our previously developed DNA microarray, based on the detection of variable regions in the 16S rDNA gene (rrs), which are specific for each selected bacterial genus, allowed the concurrent detection of Borrelia spp., Anaplasma spp., Francisella spp., Rickettsia spp. and Coxiella spp.
Methods: In this study, we developed a comprehensive detection system consisting of a second generation DNA microarray and quantitative PCRs. New oligonucleotide capture probes specific for Borrelia burgdorferi s.l. genospecies and Candidatus Neoehrlichia mikurensis were included. This new DNA microarray system required substantial changes in solution composition, hybridization conditions and post-hybridization washes.
Results: This second generation chip displayed high specificity and sensitivity. The specificity of the capture probes was tested by hybridizing the DNA microarrays with Cy5-labeled, PCR-generated amplicons encoding the rrs genes of both target and non-target bacteria. The detection limit was determined to be 10(3) genome copies, which corresponds to 1-2 pg of DNA. A given sample was evaluated as positive if its mean fluorescence was at least 10% of the mean fluorescence of a positive control. Those samples with fluorescence close to the threshold were further analyzed using quantitative PCRs, developed to identify Francisella spp., Rickettsia spp. and Coxiella spp. Like the DNA microarray, the qPCRs were based on the genus specific variable regions of the rrs gene. No unspecific cross-reactions were detected. The detection limit for Francisella spp. was determined to be only 1 genome copy, for Coxiella spp. 10 copies, and for Rickettsia spp., 100 copies.
Conclusions: Our detection system offers a rapid method for the comprehensive identification of tick-borne bacteria, which is applicable to clinical samples. It can also be used to identify both pathogenic and endosymbiontic bacteria in ticks for eco-epidemiological studies, tick laboratory colony testing, and many other applications.
Impact of two sp. on the response of diverse genotypes under salt stress.
Ilahi H, Zampieri E, Sbrana C, Brescia F, Giovannini L, Mahmoudi R Physiol Mol Biol Plants. 2024; 30(2):249-267.
PMID: 38623163 PMC: 11016052. DOI: 10.1007/s12298-024-01419-8.
Zampieri E, Franchi E, Giovannini L, Brescia F, Sillo F, Fusini D Front Plant Sci. 2023; 14:1297090.
PMID: 38078116 PMC: 10706133. DOI: 10.3389/fpls.2023.1297090.
Tick-Borne Pathogens Screening Using a Multiplex Real-Time Polymerase Chain Reaction-Based Method.
Cardenas-Cadena S, Castaneda-Lopez M, Mollinedo-Montano F, Vazquez-Reyes S, Lara-Arias J, Marino-Martinez I Acta Parasitol. 2023; 68(3):705-710.
PMID: 37531009 PMC: 10462521. DOI: 10.1007/s11686-023-00702-0.
and Strains from Olive Rhizosphere Characterized and Evaluated for Plant Growth Promoting Traits.
Schillaci M, Raio A, Sillo F, Zampieri E, Mahmood S, Anjum M Plants (Basel). 2022; 11(17).
PMID: 36079627 PMC: 9460707. DOI: 10.3390/plants11172245.
Palkova L, Tomova A, Repiska G, Babinska K, Bokor B, Mikula I Sci Rep. 2021; 11(1):6781.
PMID: 33762692 PMC: 7991656. DOI: 10.1038/s41598-021-86378-w.