BACKGROUND: The increase in syphilis rates worldwide necessitates development of a vaccine with global efficacy. We aimed to explore Treponema pallidum subspecies pallidum (TPA) molecular epidemiology essential for vaccine research by analysing clinical data and specimens from early syphilis patients using whole-genome sequencing (WGS) and publicly available WGS data. METHODS: In this multicentre, cross-sectional, molecular epidemiology study, we enrolled patients with primary, secondary, or early latent syphilis from clinics in China, Colombia, Malawi, and the USA between Nov 28, 2019, and May 27, 2022. Participants aged 18 years or older with laboratory confirmation of syphilis by direct detection methods or serological testing, or both, were included. Patients were excluded from enrolment if they were unwilling or unable to give informed consent, did not understand the study purpose or nature of their participation, or received antibiotics active against syphilis in the past 30 days. TPA detection and WGS were conducted on lesion swabs, skin biopsies, skin scrapings, whole blood, or rabbit-passaged isolates. We compared our WGS data to publicly available genomes and analysed TPA populations to identify mutations associated with lineage and geography. FINDINGS: We screened 2802 patients and enrolled 233 participants, of whom 77 (33%) had primary syphilis, 154 (66%) had secondary syphilis, and two (1%) had early latent syphilis. The median age of participants was 28 years (IQR 22-35); 154 (66%) participants were cisgender men, 77 (33%) were cisgender women, and two (1%) were transgender women. Of the cisgender men, 66 (43%) identified as gay, bisexual, or other sexuality. Among all participants, 56 (24%) had HIV co-infection. WGS data from 113 participants showed a predominance of SS14-lineage strains with geographical clustering. Phylogenomic analyses confirmed that Nichols-lineage strains were more genetically diverse than SS14-lineage strains and clustered into more distinct subclades. Differences in single nucleotide variants (SNVs) were evident by TPA lineage and geography. Mapping of highly differentiated SNVs to three-dimensional protein models showed population-specific substitutions, some in outer membrane proteins (OMPs) of interest. INTERPRETATION: Our study substantiates the global diversity of TPA strains. Additional analyses to explore TPA OMP variability within strains is vital for vaccine development and understanding syphilis pathogenesis on a population level. FUNDING: US National Institutes of Health National Institute for Allergy and Infectious Disease, the Bill & Melinda Gates Foundation, Connecticut Children's, and the Czech Republic National Institute of Virology and Bacteriology.
- MeSH
- bakteriální vakcíny imunologie aplikace a dávkování MeSH
- dospělí MeSH
- fylogeneze MeSH
- genetická variace genetika MeSH
- genom bakteriální MeSH
- genomika MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- molekulární epidemiologie * MeSH
- průřezové studie MeSH
- sekvenování celého genomu * MeSH
- syfilis * epidemiologie mikrobiologie MeSH
- Treponema pallidum * genetika imunologie MeSH
- Treponema MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- Geografické názvy
- Spojené státy americké MeSH
The treponemes infecting lagomorphs include Treponema paraluisleporidarum ecovar Cuniculus (TPeC) and ecovar Lepus (TPeL), infecting rabbits and hares, respectively. In this study, we described the first complete genome sequence of TPeL, isolate V3603-13, from an infected mountain hare (Lepus timidus) in Sweden. In addition, we determined 99.0% of the genome sequence of isolate V246-08 (also from an infected mountain hare, Sweden) and 31.7% of the genome sequence of isolate Z27 A77/78 (from a European hare, Lepus europeaus, The Netherlands). The TPeL V3603-13 genome had considerable gene synteny with the TPeC Cuniculi A genome and with the human pathogen T. pallidum, which causes syphilis (ssp. pallidum, TPA), yaws (ssp. pertenue, TPE) and endemic syphilis (ssp. endemicum, TEN). Compared to the TPeC Cuniculi A genome, TPeL V3603-13 contained four insertions and 11 deletions longer than three nucleotides (ranging between 6 and2,932 nts). In addition, there were 25 additional indels, from one to three nucleotides long, altogether spanning 36 nts. The number of single nucleotide variants (SNVs) between TPeC Cuniculi A and TPeL V3603-13 were represented by 309 nucleotide differences. Major proteome coding differences between TPeL and TPeC were found in the tpr gene family, and (predicted) genes coding for outer membrane proteins, suggesting that these components are essential for host adaptation in lagomorph syphilis. The phylogeny revealed that the TPeL sample from the European brown hare was more distantly related to TPeC Cuniculi A than V3603-13 and V246-08.
- MeSH
- fylogeneze * MeSH
- genom bakteriální MeSH
- králíci MeSH
- syfilis * mikrobiologie MeSH
- Treponema * genetika izolace a purifikace MeSH
- zajíci * mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Syphilis is a multistage sexually transmitted disease caused by Treponema pallidum ssp. pallidum. In the Czech Republic, there are around 700-800 new syphilis cases annually, continuously increasing since 2012. This study analyzed a total of 1228 samples from 2004 to 2022. Of the PCR-positive typeable samples (n = 415), 68.7% were fully-typed (FT), and 31.3% were partially-typed. Most of the identified isolates belonged to the SS14-clade and only 6.3% were the Nichols-like cluster. While in the beginning of sample collection isolates have been macrolide-susceptible, recent isolates are completely resistant to macrolides. Among the FT samples, 34 different allelic profiles (APs) were found. Most of the profiles (n = 27) appeared just once in the Czech population, while seven profiles were detected more than twice. The most frequent APs belonged to two separate groups of SS14-like isolates, including group of 1.3.1 (ST 1) and 1.26.1 (ST 25) profiles, and the second group containing 1.1.8 (ST 3), 1.1.1 (ST 2), and 1.1.3 (ST 11) (representing 57.5%, and 25.3% of all detected APs, respectively). Both groups consistently differed in 6 nucleotide positions in five genes (TP0150, TP0324, TP0515, TP0548, and TP0691) coding amino-acid replacements suggesting that one or more of these differences could be involved in the higher success of the first group.
- MeSH
- alely * MeSH
- dospělí MeSH
- genotyp MeSH
- lidé středního věku MeSH
- lidé MeSH
- makrolidy farmakologie MeSH
- multilokusová sekvenční typizace * MeSH
- syfilis * mikrobiologie epidemiologie genetika MeSH
- Treponema pallidum * genetika izolace a purifikace MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
The incidence of syphilis has risen worldwide in the last decade in spite of being an easily treated infection. The causative agent of this sexually transmitted disease is the bacterium Treponema pallidum subspecies pallidum (TPA), very closely related to subsp. pertenue (TPE) and endemicum (TEN), responsible for the human treponematoses yaws and bejel, respectively. Although much focus has been placed on the question of the spatial and temporary origins of TPA, the processes driving the evolution and epidemiological spread of TPA since its divergence from TPE and TEN are not well understood. Here, we investigate the effects of recombination and selection as forces of genetic diversity and differentiation acting during the evolution of T. pallidum subspecies. Using a custom-tailored procedure, named phylogenetic incongruence method, with 75 complete genome sequences, we found strong evidence for recombination among the T. pallidum subspecies, involving 12 genes and 21 events. In most cases, only one recombination event per gene was detected and all but one event corresponded to intersubspecies transfers, from TPE/TEN to TPA. We found a clear signal of natural selection acting on the recombinant genes, which is more intense in their recombinant regions. The phylogenetic location of the recombination events detected and the functional role of the genes with signals of positive selection suggest that these evolutionary processes had a key role in the evolution and recent expansion of the syphilis bacteria and significant implications for the selection of vaccine candidates and the design of a broadly protective syphilis vaccine.
- MeSH
- frambézie * mikrobiologie MeSH
- fylogeneze MeSH
- infekce bakteriemi rodu Treponema * mikrobiologie MeSH
- lidé MeSH
- syfilis * epidemiologie mikrobiologie MeSH
- Treponema pallidum genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
Nestr.
Treponema pallidum subsp. pallidum (TPA) is the causative agent of syphilis. More than 10 million of new syphilis cases are diagnosed annually. Two different typing systems were established for molecular characterization of TPA clinical isolates, however, their typing efficiency and discriminatory power was found to be highly variable. The aim of this project is to develop a new, highly effective molecular typing scheme preferentially targeting sequences encoding proteome differences, since they can be the cause of different clinical manifestation. The discrimination power of the new typing system will be assessed on genetically diverse clinical isolates and strains of different geographical origin. The knowledge of genetic differences of contemporary syphilis strains is essential due to continuing efforts of syphilis vaccine development. The new typing scheme will be applied on clinical samples from Czech Republic to obtain the information about variability and number of particular genotypes in the Czech Republic. Molecular data will be correlated with epidemiological data.
Treponema pallidum subsp. pallidum (TPA) je původcem venerického onemocnění syfilis. Celosvětově je ročně diagnostikováno přes 10 milionů nových případů syfilis. S rozvojem genomiky došlo k vývoji dvou molekulárně-typizačních systémů pro charakterizaci klinických kmenů TPA, avšak jejich účinnost typování a rozlišovací schopnost značně kolísá. Cílem tohoto projektu je vytvořit nový, vysoce spolehlivý a účinný molekulární typovací systém, zaměřený na sekvence kódující proteomické rozdíly mezi TPA kmeny, které mohou být důvodem rozdílné klinické manifestace. Rozlišovací schopnost typovacího systému bude testována na geneticky odlišných klinických izolátech a vzorcích pocházejících z různých míst světa. Znalost genetické podstaty současných klinických kmenů TPA je zásadní i z hlediska pokračujících snah o vývoj vakcíny proti syfilis. Aplikace nového typovacího systému na klinické kmeny z České republiky přinese informace o odlišnosti a zastoupení jednotlivých genotypů TPA na našem území. Molekulární data budou korelována s dostupnými epidemiologickými údaji.
- MeSH
- lidé MeSH
- molekulární typizace metody MeSH
- proteomika MeSH
- syfilis diagnóza genetika mikrobiologie MeSH
- Treponema pallidum genetika izolace a purifikace MeSH
- Check Tag
- lidé MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- bakteriologie
- dermatovenerologie
- genetika, lékařská genetika
- NLK Publikační typ
- závěrečné zprávy o řešení grantu AZV MZ ČR
BACKGROUND: Whole-genome sequencing (WGS) of Treponema pallidum subspecies pallidum (TPA) has been constrained by the lack of in vitro cultivation methods for isolating spirochetes from patient samples. METHODS: We built upon recently developed enrichment methods to sequence TPA directly from primary syphilis chancre swabs collected in Guangzhou, China. RESULTS: By combining parallel, pooled whole-genome amplification with hybrid selection, we generated high-quality genomes from 4 of 8 chancre-swab samples and 2 of 2 rabbit-passaged isolates, all subjected to challenging storage conditions. CONCLUSIONS: This approach enabled the first WGS of Chinese samples without rabbit passage and provided insights into TPA genetic diversity in China.
- MeSH
- králíci MeSH
- lidé MeSH
- sekvenování celého genomu MeSH
- syfilis * diagnóza mikrobiologie MeSH
- Treponema pallidum klasifikace genetika MeSH
- tvrdý vřed * diagnóza mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Čína MeSH
Treponema pallidum subsp. endemicum (TEN) is the causative agent of endemic syphilis (bejel). Until now, only a single TEN strain, Bosnia A, has been completely sequenced. The only other laboratory TEN strain available, Iraq B, was isolated in Iraq in 1951 by researchers from the US Centers for Disease Control and Prevention. In this study, the complete genome of the Iraq B strain was amplified as overlapping PCR products and sequenced using the pooled segment genome sequencing method and Illumina sequencing. Total average genome sequencing coverage reached 3469×, with a total genome size of 1,137,653 bp. Compared to the genome sequence of Bosnia A, a set of 37 single nucleotide differences, 4 indels, 2 differences in the number of tandem repetitions, and 18 differences in the length of homopolymeric regions were found in the Iraq B genome. Moreover, the tprF and tprG genes that were previously found deleted in the genome of the TEN Bosnia A strain (spanning 2.3 kb in length) were present in a subpopulation of TEN Iraq B and Bosnia A microbes, and their sequence was highly similar to those found in T. p. subsp. pertenue strains, which cause the disease yaws. The genome sequence of TEN Iraq B revealed close genetic relatedness between both available bejel-causing laboratory strains (i.e., Iraq B and Bosnia A) and also genetic variability within the bejel treponemes comparable to that found within yaws- or syphilis-causing strains. In addition, genetic relatedness to TPE strains was demonstrated by the sequence of the tprF and tprG genes found in subpopulations of both TEN Iraq B and Bosnia A. The loss of the tprF and tprG genes in most TEN microbes suggest that TEN genomes have been evolving via the loss of genomic regions, a phenomenon previously found among the treponemes causing both syphilis and rabbit syphilis.
- MeSH
- bakteriální geny MeSH
- frambézie mikrobiologie MeSH
- fylogeneze MeSH
- genom bakteriální MeSH
- infekce bakteriemi rodu Treponema mikrobiologie MeSH
- proteiny vnější bakteriální membrány genetika MeSH
- sekvenování celého genomu MeSH
- syfilis mikrobiologie MeSH
- Treponema pallidum genetika MeSH
- Treponema genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Bosna a Hercegovina MeSH
BACKGROUND: Treponema pallidum subspecies pallidum (TPA) and subsp. endemicum (TEN) are the causative agents of syphilis and bejel, respectively. TEN shows similar clinical manifestations and is morphologically and serologically indistinguishable from TPA. Recently, bejel was found outside of its assumed endemic areas. Using molecular typing we aimed to discover bejel and characterize circulating TPA types among syphilis cases with Surinamese, Antillean and Dutch ethnicity in Amsterdam. METHODS: DNA was extracted from 137 ulcer swabs, which tested positive in the in-house diagnostic PCR targeting the polA gene. Samples were collected between 2006 and 2018 from Surinamese, Antillean and Dutch patients attending the Amsterdam STI clinic. Multilocus sequence typing was performed by partial sequence analysis of the tp0136, tp0548 and tp0705 genes. In addition, the 23S rRNA loci were analyzed for A2058G and A2059G macrolide resistance mutations. RESULTS: We found 17 distinct allelic profiles in 103/137 (75%) fully typed samples, which were all TPA and none TEN. Of the strains, 82.5% were SS14-like and 17.5% Nichols-like. The prevalence of Nichols-like strains found in this study is relatively high compared to nearby countries. The most prevalent types were 1.3.1 (42%) and 1.1.1 (19%), in concordance with similar TPA typing studies. The majority of the TPA types found were unique per country. New allelic types (7) and profiles (10) were found. The successfully sequenced 23S rRNA loci from 123/137 (90%) samples showed the presence of 79% A2058G and 2% A2059G mutations. CONCLUSIONS: No TEN was found in the samples from different ethnicities residing in Amsterdam, the Netherlands, so no misdiagnoses occurred. Bejel has thus not (yet) spread as a sexually transmitted disease in the Netherlands. The strain diversity found in this study reflects the local male STI clinic population which is a diverse, mixed group.
- MeSH
- alely MeSH
- bakteriální geny * MeSH
- dospělí MeSH
- etnicita statistika a číselné údaje MeSH
- lidé MeSH
- syfilis epidemiologie etnologie mikrobiologie MeSH
- taxonomické DNA čárové kódování MeSH
- Treponema pallidum klasifikace genetika patogenita MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Nizozemské Antily MeSH
- Nizozemsko MeSH
- Surinam MeSH
BACKGROUND: Pathogenic treponemes related to Treponema pallidum are both human (causing syphilis, yaws, bejel) and animal pathogens (infections of primates, venereal spirochetosis in rabbits). A set of 11 treponemal genome sequences including those of five Treponema pallidum ssp. pallidum (TPA) strains (Nichols, DAL-1, Mexico A, SS14, Chicago), four T. p. ssp. pertenue (TPE) strains (CDC-2, Gauthier, Samoa D, Fribourg-Blanc), one T. p. ssp. endemicum (TEN) strain (Bosnia A) and one strain (Cuniculi A) of Treponema paraluisleporidarum ecovar Cuniculus (TPeC) were tested for the presence of positively selected genes. METHODOLOGY/PRINCIPAL FINDINGS: A total of 1068 orthologous genes annotated in all 11 genomes were tested for the presence of positively selected genes using both site and branch-site models with CODEML (PAML package). Subsequent analyses with sequences obtained from 62 treponemal draft genomes were used for the identification of positively selected amino acid positions. Synthetic biotinylated peptides were designed to cover positively selected protein regions and these peptides were tested for reactivity with the patient's syphilis sera. Altogether, 22 positively selected genes were identified in the TP genomes and TPA sets of positively selected genes differed from TPE genes. While genetic variability among TPA strains was predominantly present in a number of genetic loci, genetic variability within TPE and TEN strains was distributed more equally along the chromosome. Several syphilitic sera were shown to react with some peptides derived from the protein sequences evolving under positive selection. CONCLUSIONS/SIGNIFICANCE: The syphilis-, yaws-, and bejel-causing strains differed relative to sets of positively selected genes. Most of the positively selected chromosomal loci were identified among the TPA treponemes. The local accumulation of genetic variability suggests that the diversification of TPA strains took place predominantly in a limited number of genomic regions compared to the more dispersed genetic diversity differentiating TPE and TEN strains. The identification of positively selected sites in tpr genes and genes encoding outer membrane proteins suggests their role during infection of human and animal hosts. The driving force for adaptive evolution at these loci thus appears to be the host immune response as supported by observed reactivity of syphilitic sera with some peptides derived from protein sequences showing adaptive evolution.
- MeSH
- bakteriální geny * MeSH
- biologická adaptace * MeSH
- dospělí MeSH
- genomika MeSH
- genotyp * MeSH
- lidé MeSH
- mladý dospělý MeSH
- selekce (genetika) MeSH
- syfilis mikrobiologie patologie MeSH
- Treponema pallidum klasifikace genetika izolace a purifikace MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A recently introduced Multilocus Sequence Typing scheme for Treponema pallidum subsp. pallidum was applied to clinical samples collected from 2004 to 2017 from the two largest cities (Prague and Brno) in the Czech Republic. Altogether, a total of 675 samples were tested in this study and 281 of them were found PCR-positive for treponemal DNA and typeable. Most of the typed samples (n = 281) were swabs from primary or secondary syphilis lesions (n = 231), and only a minority were whole blood or tissue samples (n = 50). Swab samples from patients with rapid plasma regain (RPR) values of 1-1024 were more frequently PCR-positive (84.6%) compared to samples from patients with non-reactive RPR test (46.5%; p-value = 0.0001). Out of 281 typeable samples, 136 were fully-typed at all TP0136, TP0548, and TP0705 loci. Among the fully and partially typed samples, 25 different allelic profiles were identified. Altogether, eight novel allelic variants were found among fully (n = 5) and partially (n = 3) typed samples. The distribution of TPA allelic profiles identified in the Czech Republic from 2004 to 2017 revealed a dynamic character with allelic profiles disappearing and emerging over time. While the number of samples with the A2058G mutation was seen to increase (86.7% in 2016/2017), the number of samples harboring the A2059G mutation was found to have decreased over time (3.3% in 2016/2017). In addition, we found several allelic profile associations with macrolide resistance or susceptibility, the gender of patients, as well as patient residence.
- MeSH
- alely MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- DNA bakterií genetika MeSH
- dospělí MeSH
- genotyp MeSH
- lidé MeSH
- mladý dospělý MeSH
- multilokusová sekvenční typizace * MeSH
- RNA ribozomální 23S genetika MeSH
- syfilis genetika mikrobiologie patologie MeSH
- Treponema pallidum genetika patogenita MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH