Genetic Characterization of Trichomonas vaginalis Isolates by Use of Multilocus Sequence Typing

Abstract

dIn this study, we introduce a multilocus sequence typing (MLST) scheme, comprised of seven single-copy housekeeping genes, to genetically characterize Trichomonas vaginalis. Sixty-eight historical and recent isolates of T. vaginalis were sampled from the American Type Culture Collection and female patients at area health care facilities, respectively, to assess the usefulness of this typing method. Forty-three polymorphic nucleotide sites, 51 different alleles, and 60 sequence types were distinguished among the 68 isolates, revealing a diverse T. vaginalis population. Moreover, this discriminatory MLST scheme retains the ability to identify epidemiologically linked isolates such as those collected from sexual partners. Population genetic and phylogenetic analyses determined that T. vaginalis population structure is strongly influenced by recombination and is composed of two separate populations that may be nonclonal. MLST is useful for investigating the epidemiology, genetic diversity, and population structure of T. vaginalis.

Trichomonas vaginalis Metronidazole Resistance Is Associated with Single Nucleotide Polymorphisms in the Nitroreductase Genes ntr4 Tv and ntr6 Tv

“…Other studies have demonstrated that laboratory-generated resistance is associated with reduced thioredoxin reductase activity and free flavins, both of which are proposed to reduce metronidazole as well (7,8), and decreased flavin reductase activity has been observed in resistant clinical isolates (9). Lastly, another study identified 11 nitroreductase genes in the T. vaginalis genome (6), at least one of which was capable of metronidazole reduction (10). We hypothesized that loss of function of one or more of these nitroreductase proteins could mediate metronidazole resistance in some T. vaginalis isolates.…”

“…Prior studies using microsatellite genotyping and multilocus sequence typing (MLST) have shown that T. vaginalis has a two-type population structure, with one population highly similar to an inferred ancestral population (type 1) and a second population that is more divergent and exhibits a higher degree of metronidazole resistance (type 2) (10,14). To determine the population structure of our isolate collection, we utilized the MLST methodology (10). Briefly, we PCR amplified and sequenced seven different loci using template DNA from 100 isolates (50 each metronidazole resistant and susceptible), using the primers listed in Table 1.…”

“…Although we had identified SNPs with strong associations with metronidazole resistance, it is important that they be interpreted in light of the T. vaginalis population structure. Prior studies using microsatellite genotyping and multilocus sequence typing (MLST) have shown that T. vaginalis has a two-type population structure, with one population highly similar to an inferred ancestral population (type 1) and a second population that is more divergent and exhibits a higher degree of metronidazole resistance (type 2) (10,14). To determine the population structure of our isolate collection, we utilized the MLST methodology (10).…”

Unique <i>Trichomonas vaginalis</i> gene sequences identified in multinational regions of Northwest China

“…Several T. vaginalis sequences have been reported to date, and most of the 18S gene sequences have been reported in Chinese and Philippine studies (17)(18)(19). Previous studies indicate a relationship between T. vaginalis genotype and the clinical presentation of trichomoniasis (7,20,21). In this study, a distancebased network was constructed with three large clusters and many branches.…”

Determination of Trichomonas vaginalis Genotypes Using PCR-Restriction Fragment Length Polymorphism (RFLP)

“…Bu çalışmada Aydın'da vajinit ön tanılı olgulardan elde edilen T. vaginalis izolatlarının aktin geni-RFLP paternlerine göre genotiplendirinin belirlenmesi amaçlanmıştır. Moleküler tiplendirme çalışmaları ile belirli topluluklarda T. vaginalis'in genetik çeşitliliği, popülasyon yapısı ve epidemiyolojik bağlan-tıları hakkında bilgi sahibi olunabilmektedir (18,19). Ayrıca, genetik çeşitliliğinin araştırılması parazitin patojenitesini, TVV ilişkisini, ilaç direncini ve tekrarlayan enfeksiyonların kaynağını belirlemeye bü-yük katkı sağlayacağı düşünülmektedir (10,20,21).…”