scholarly journals Origin of modern syphilis and emergence of a contemporary pandemic cluster

2016 ◽  
Author(s):  
Natasha Arora ◽  
Verena J. Schuenemann ◽  
Günter Jäger ◽  
Alexander Peltzer ◽  
Alexander Seitz ◽  
...  

AbstractSyphilis swept across the world in the 16th century as one of most prominent documented pandemics and is re-emerging worldwide despite the availability of effective antibiotics. Little is known about the genetic patterns in current infections or the evolutionary origins of the disease due to the non-cultivable and clonal nature of the causative bacterium Treponema pallidum subsp. pallidum. In this study, we used DNA capture and next generation sequencing to obtain whole genome data from syphilis patient specimens and from treponemes propagated in laboratory settings. Phylogenetic analyses indicate that the syphilis strains examined here share a common ancestor after the 15th century. Moreover, most contemporary strains are azithromycin resistant and members of a globally dominant cluster named here as SS14-Ω. This cluster diversified from a common ancestor in the mid-20th century and has the population genetic and epidemiological features indicative of the emergence of a pandemic strain cluster.

2016 ◽  
Author(s):  
Ajith Harish ◽  
Aare Abroi ◽  
Julian Gough ◽  
Charles Kurland

AbstractThe evolutionary origins of viruses according to marker gene phylogenies, as well as their relationships to the ancestors of host cells remains unclear. In a recent article Nasir and Caetano-Anollés reported that their genome-scale phylogenetic analyses identify an ancient origin of the “viral supergroup” (Nasir et al (2015) A phylogenomic data-driven exploration of viral origins and evolution. Science Advances, 1(8):e1500527). It suggests that viruses and host cells evolved independently from a universal common ancestor. Examination of their data and phylogenetic methods indicates that systematic errors likely affected the results. Reanalysis of the data with additional tests shows that small-genome attraction artifacts distort their phylogenomic analyses. These new results indicate that their suggestion of a distinct ancestry of the viral supergroup is not well supported by the evidence.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhiwei Chen ◽  
Longhua Zhou ◽  
Panpan Jiang ◽  
Ruiju Lu ◽  
Nigel G. Halford ◽  
...  

Abstract Background Sucrose nonfermenting-1 (SNF1)-related protein kinases (SnRKs) play important roles in regulating metabolism and stress responses in plants, providing a conduit for crosstalk between metabolic and stress signalling, in some cases involving the stress hormone, abscisic acid (ABA). The burgeoning and divergence of the plant gene family has led to the evolution of three subfamilies, SnRK1, SnRK2 and SnRK3, of which SnRK2 and SnRK3 are unique to plants. Therefore, the study of SnRKs in crops may lead to the development of strategies for breeding crop varieties that are more resilient under stress conditions. In the present study, we describe the SnRK gene family of barley (Hordeum vulgare), the widespread cultivation of which can be attributed to its good adaptation to different environments. Results The barley HvSnRK gene family was elucidated in its entirety from publicly-available genome data and found to comprise 50 genes. Phylogenetic analyses assigned six of the genes to the HvSnRK1 subfamily, 10 to HvSnRK2 and 34 to HvSnRK3. The search was validated by applying it to Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) genome data, identifying 50 SnRK genes in rice (four OsSnRK1, 11 OsSnRK2 and 35 OsSnRK3) and 39 in Arabidopsis (three AtSnRK1, 10 AtSnRK2 and 26 AtSnRK3). Specific motifs were identified in the encoded barley proteins, and multiple putative regulatory elements were found in the gene promoters, with light-regulated elements (LRE), ABA response elements (ABRE) and methyl jasmonate response elements (MeJa) the most common. RNA-seq analysis showed that many of the HvSnRK genes responded to ABA, some positively, some negatively and some with complex time-dependent responses. Conclusions The barley HvSnRK gene family is large, comprising 50 members, subdivided into HvSnRK1 (6 members), HvSnRK2 (10 members) and HvSnRK3 (34 members), showing differential positive and negative responses to ABA.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Nika Pende ◽  
Adrià Sogues ◽  
Daniela Megrian ◽  
Anna Sartori-Rupp ◽  
Patrick England ◽  
...  

AbstractMost archaea divide by binary fission using an FtsZ-based system similar to that of bacteria, but they lack many of the divisome components described in model bacterial organisms. Notably, among the multiple factors that tether FtsZ to the membrane during bacterial cell constriction, archaea only possess SepF-like homologs. Here, we combine structural, cellular, and evolutionary analyses to demonstrate that SepF is the FtsZ anchor in the human-associated archaeon Methanobrevibacter smithii. 3D super-resolution microscopy and quantitative analysis of immunolabeled cells show that SepF transiently co-localizes with FtsZ at the septum and possibly primes the future division plane. M. smithii SepF binds to membranes and to FtsZ, inducing filament bundling. High-resolution crystal structures of archaeal SepF alone and in complex with the FtsZ C-terminal domain (FtsZCTD) reveal that SepF forms a dimer with a homodimerization interface driving a binding mode that is different from that previously reported in bacteria. Phylogenetic analyses of SepF and FtsZ from bacteria and archaea indicate that the two proteins may date back to the Last Universal Common Ancestor (LUCA), and we speculate that the archaeal mode of SepF/FtsZ interaction might reflect an ancestral feature. Our results provide insights into the mechanisms of archaeal cell division and pave the way for a better understanding of the processes underlying the divide between the two prokaryotic domains.


1989 ◽  
Vol 67 (6) ◽  
pp. 306-310 ◽  
Author(s):  
Morris F. Manolson ◽  
Judith M. Percy ◽  
David K. Apps ◽  
Xiao-Song Xie ◽  
Dennis K. Stone ◽  
...  

The evolution of the endomembrane systems of eukaryotic cells can be examined by exploring the evolutionary origins of the endomembrane H+-ATPases. Recent studies suggest that certain polypeptides are common to all H+ pumps of this type. Tonoplast H+ -ATPase from Beta vulgaris L. was purified and antibodies raised to two of its subunits. Each of these antisera reacted with a polypeptide of the corresponding size in bovine chromaffin granules, bovine clathrincoated vesicles, and yeast vacuolar membranes, suggesting common structural features and a common ancestor for endomembrane H+-ATPases of different organelles and different kingdoms. The antiserum raised against the 57-kDa polypeptide of plant tonoplast H+ -ATPase also reacted with subunit "a" of the H+-ATPase from the obligately anaerobic bacterium Clostridium pasteurianum and to the α subunit of the H+ -ATPase from Escherichia coli. There was no reactivity with chloroplast or mitochondrial ATPases. These results are discussed in relation to recent sequence data which suggest that endomembrane H+-ATPases may be evolutionarily related to the F0F1 ATPases.Key words: H+ -ATPase, evolution, immunology, vacuole, endomembrane.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shingo Nishiki ◽  
Kenichi Lee ◽  
Mizue Kanai ◽  
Shu-ichi Nakayama ◽  
Makoto Ohnishi

AbstractJapan has had a substantial increase in syphilis cases since 2013. However, research on the genomic features of the Treponema pallidum subspecies pallidum (TPA) strains from these cases has been limited. Here, we elucidated the genetic variations and relationships between TPA strains in Japan (detected between 2014 and 2018) and other countries by whole-genome sequencing and phylogenetic analyses, including syphilis epidemiological surveillance data and information on patient sexual orientation. Seventeen of the 20 strains in Japan were SS14- and the remaining 3 were Nichols-lineage. Sixteen of the 17 SS14-lineage strains were classified into previously reported Sub-lineage 1B. Sub-lineage 1B strains in Japan have formed distinct sub-clusters of strains from heterosexuals and strains from men who have sex with men. These strains were closely related to reported TPA strains in China, forming an East-Asian cluster. However, those strains in these countries evolved independently after diverging from their most recent common ancestor and expanded their genetic diversity during the time of syphilis outbreak in each country. The genetic difference between the TPA strains in these countries was characterized by single-nucleotide-polymorphism analyses of their penicillin binding protein genes. Taken together, our results elucidated the detailed phylogenetic features and transmission networks of syphilis.


2019 ◽  
Vol 5 (4) ◽  
pp. eaav3875 ◽  
Author(s):  
J. Luque ◽  
R. M. Feldmann ◽  
O. Vernygora ◽  
C. E. Schweitzer ◽  
C. B. Cameron ◽  
...  

Evolutionary origins of novel forms are often obscure because early and transitional fossils tend to be rare, poorly preserved, or lack proper phylogenetic contexts. We describe a new, exceptionally preserved enigmatic crab from the mid-Cretaceous of Colombia and the United States, whose completeness illuminates the early disparity of the group and the origins of novel forms. Its large and unprotected compound eyes, small fusiform body, and leg-like mouthparts suggest larval trait retention into adulthood via heterochronic development (pedomorphosis), while its large oar-like legs represent the earliest known adaptations in crabs for active swimming. Our phylogenetic analyses, including representatives of all major lineages of fossil and extant crabs, challenge conventional views of their evolution by revealing multiple convergent losses of a typical “crab-like” body plan since the Early Cretaceous. These parallel morphological transformations may be associated with repeated invasions of novel environments, including the pelagic/necto-benthic zone in this pedomorphic chimera crab.


2009 ◽  
Vol 57 (4) ◽  
pp. 167 ◽  
Author(s):  
Gavin Huttley

Did the mammal radiation arise through initial divergence of prototherians from a common ancestor of metatherians and eutherians, the Theria hypothesis, or of eutherians from a common ancestor of metatherians and prototherians, the Marsupionta hypothesis? Molecular phylogenetic analyses of point substitutions applied to this problem have been contradictory – mtDNA-encoded sequences supported Marsupionta, nuclear-encoded sequences and RY (purine–pyrimidine)-recoded mtDNA supported Theria. The consistency property of maximum likelihood guarantees convergence on the true tree only with longer alignments. Results from analyses of genome datasets should therefore be impervious to choice of outgroup. We assessed whether important hypotheses concerning mammal evolution, including Theria/Marsupionta and the branching order of rodents, carnivorans and primates, are resolved by phylogenetic analyses using ~2.3 megabases of protein-coding sequence from genome projects. In each case, only two tree topologies were being compared and thus inconsistency in resolved topologies can only derive from flawed models of sequence divergence. The results from all substitution models strongly supported Theria. For the eutherian lineages, all models were sensitive to the outgroup. We argue that phylogenetic inference from point substitutions will remain unreliable until substitution models that better match biological mechanisms of sequence divergence have been developed.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yonghua Wu

Abstract Background Many living birds exhibit some nocturnal activity, but the genetic basis and evolutionary origins of their nocturnality remain unknown. Results Here, we used a molecular phyloecological approach to analyze the adaptive evolution of 33 phototransduction genes in diverse bird lineages. Our results suggest that functional enhancement of two night-vision genes, namely, GRK1 and SLC24A1, underlies the nocturnal adaption of living birds. Further analyses showed that the diel activity patterns of birds have remained relatively unchanged since their common ancestor, suggesting that the widespread nocturnal activity of many living birds may largely stem from their common ancestor rather than independent evolution. Despite this evolutionary conservation of diel activity patterns in birds, photoresponse recovery genes were found to be frequently subjected to positive selection in diverse bird lineages, suggesting that birds generally have evolved an increased capacity for motion detection. Moreover, we detected positive selection on both dim-light vision genes and bright-light vision genes in the class Aves, suggesting divergent evolution of the vision of birds from that of reptiles and that different bird lineages have evolved certain visual adaptions to their specific light conditions. Conclusions This study suggests that the widespread nocturnality of extant birds has a deep evolutionary origin tracing back to their common ancestor.


1998 ◽  
Vol 88 (8) ◽  
pp. 782-787 ◽  
Author(s):  
Drake C. Stenger ◽  
Jeffrey S. Hall ◽  
Il-Ryong Choi ◽  
Roy French

The complete nucleotide sequence of wheat streak mosaic virus (WSMV) has been determined based on complementary DNA clones derived from the 9,384-nucleotide (nt) RNA of the virus. The genome of WSMV has a 130-nt 5′ leader and 149-nt 3′-untranslated region and is polyadenylated at the 3′ end. WSMV RNA encodes a single polyprotein of 3,035 amino acid residues and has a deduced genome organization typical for a member of the family Potyviridae (5′-P1/HC-Pro/P3/6K1/CI/6K2/VPg-NIa/NIb/CP-3′). Because WSMV shares with ryegrass mosaic virus (RGMV) the biological property of transmission by eriophyid mites, WSMV has been assigned to the genus Rymovirus, of which RGMV is the type species. Phylogenetic analyses were conducted with complete polyprotein or NIb protein sequences of 11 members of the family Potyviridae, including viruses of monocots or dicots and viruses transmitted by aphids, whiteflies, and mites. WSMV and the monocot-infecting, mite-transmitted brome streak mosaic virus (BrSMV) are sister taxa and share a most recent common ancestor with the whitefly-transmitted sweet potato mild mottle virus, the type species of the proposed genus “Ipomovirus.” In contrast, RGMV shares a most recent common ancestor with aphid-transmitted species of the genus Potyvirus. These results indicate that WSMV and BrSMV should be classified within a new genus of the family Potyviridae and should not be considered species of the genus Rymovirus.


Sign in / Sign up

Export Citation Format

Share Document