RESUMO
Spirochetal bacteria were successfully isolated from mosquitoes (Culex pipiens, Aedes cinereus) in the Czech Republic between 1999 and 2002. Preliminary 16S rRNA phylogenetic sequence analysis showed that these strains differed significantly from other spirochetal genera within the family Spirochaetaceae and suggested a novel bacterial genus in this family. To obtain more comprehensive genomic information of these isolates, we used Illumina MiSeq and Oxford Nanopore technologies to sequence four genomes of these spirochetes (BR151, BR149, BR193, BR208). The overall size of the genomes varied between 1.68 and 1.78 Mb; the GC content ranged from 38.5 to 45.8%. Draft genomes were compared to 36 publicly available genomes encompassing eight genera from the class Spirochaetes. A phylogeny generated from orthologous genes across all taxa and the percentage of conserved proteins (POCP) confirmed the genus status of these novel spirochetes. The genus Entomospira gen. nov. is proposed with BR151 selected as type species of the genus. For this isolate and the closest related isolate, BR149, we propose the species name Entomospira culicis sp. nov. The two other isolates BR208 and BR193 are named Entomospira nematocera sp. nov. (BR208) and Entomospira entomophilus sp. nov. (BR193). Finally, we discuss their interesting phylogenetic positioning.
Assuntos
Spirochaetales/classificação , Spirochaetales/genética , Spirochaetales/isolamento & purificação , Animais , Artrópodes/genética , Técnicas de Tipagem Bacteriana/métodos , Composição de Bases/genética , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Spirochaeta/genéticaRESUMO
Borrelia burgdorferi sensu lato (Bbsl) spirochetes include the agents of Lyme borreliosis in temperate regions of the Northern Hemisphere, and merge their transmission cycles mainly with ticks of the Ixodes ricinus complex. Twenty genospecies compose Bbsl currently, and with the exception of Borrelia chilensis, and Borrelia garinii, all have been described only for North America, Europe, North Africa, and Asia. Here, we collected specimens of Ixodes paranaensis, a tick associated with swifts in a Brazilian natural park from the state of Minas Gerais, and performed a molecular characterization of 11 borrelial genes. Based on comparisons of inter and intraspecific genetic divergences, and Bayesian phylogenetic trees inferred for 16S rRNA, flaB, p66, and concatenated clpA, clpX, pepX, pyrG, recG, nifS rlpB, and uvrA genes, we demonstrate the occurrence of a new genospecies of Bbsl. "Candidatus Borrelia ibitipoquensis" Ip37 is closely related to Borrelia sp. Am501, and Borrelia valaisiana, a spirochete transmitted by ticks of the I. ricinus complex in Eurasia that uses birds as reservoirs. In a similar ecological scenario involving ticks and avian hosts, the migratory swift Streptoprocne biscutata is the sole-documented bird associated with I. paranaensis, and, although not assessed in this study, could correspond to the vertebrate reservoir of this newly described genospecies in Brazil. Pathogenic roles of "Ca. B. ibitipoquensis" are still unknown. However, its possible vector I. paranaensis is not an anthropophilic tick, so human infections would be unlikely to occur. Our finding enhances the knowledge on Bbsl in South America, highlights the occurrence of ecologically and genetically related genospecies with vastly separated geographical distributions, and calls for the attention to explore a barely known diversity of spirochetes of this group in the region.
Assuntos
Borrelia/isolamento & purificação , Ixodes/microbiologia , Animais , Borrelia/classificação , Borrelia/genética , Brasil , Cavernas , Feminino , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Spirochaetales/classificaçãoRESUMO
There is substantial evidence supporting the role of certain oral bacteria species in the onset and progression of periodontitis. Nevertheless, results of independent-culture diagnostic methods introduced about a decade ago have pointed to the existence of new periodontal pathogens. However, the data of these studies have not been evaluated together, which may generate some misunderstanding on the actual role of these microorganisms in the etiology of periodontitis. The aim of this systematic review was to determine the current weight of evidence for newly identified periodontal pathogens based on the results of "association" studies. This review was conducted and reported in accordance with the PRISMA statement. The MEDLINE, EMBASE, and Cochrane databases were searched up to September 2013 for studies (1) comparing microbial data of subgingival plaque samples collected from subjects with periodontitis and periodontal health and (2) evaluating at least 1 microorganism other than the already-known periodontal pathogens. From 1,450 papers identified, 41 studies were eligible. The data were extracted and registered in predefined piloted forms. The results suggested that there is moderate evidence in the literature to support the association of 17 species or phylotypes from the phyla Bacteroidetes, Candidatus Saccharibacteria, Firmicutes, Proteobacteria, Spirochaetes, and Synergistetes. The phylum Candidatus Saccharibacteria and the Archaea domain also seem to have an association with disease. These data point out the importance of previously unidentified species in the etiology of periodontitis and might guide future investigations on the actual role of these suspected new pathogens in the onset and progression of this infection.
Assuntos
Bactérias/classificação , Periodontite/microbiologia , Archaea/classificação , Bactérias/isolamento & purificação , Bacteroidetes/classificação , Placa Dentária/microbiologia , Bactérias Anaeróbias Gram-Negativas/classificação , Bactérias Gram-Negativas/classificação , Humanos , Periodonto/microbiologia , Filogenia , Proteobactérias/classificação , Spirochaetales/classificaçãoRESUMO
Although molecular studies have revealed potential oral pathogens among the phyla Spirochaetes and Deferribacteres, their occurrence in endodontic infections has not been consistently investigated. In this study, we devised a nested PCR-DGGE approach to survey samples from infected root canals for the presence of members of these two phyla, and to examine their diversity. The primers used also amplified DNA from Atopobium species. Eight of 10 cases showed bands representative of the target bacterial groups. DGGE profiles revealed a mean number of 6.5 intense and faint bands. No single band occurred in all profiles. Sequences from intense bands excised from the gel showed similarities to species/phylotypes of all target groups--Flexistipes species (Deferribacteres phylum), uncharacterized spirochetes, and Atopobium species. Analysis of these data indicates that uncultivated Spirochaetes and Deferribacteres phylotypes are frequent members of the endodontic microbiota and may be potential pathogens involved with the etiology of periradicular diseases.
Assuntos
Doenças da Polpa Dentária/microbiologia , Bactérias Gram-Negativas/classificação , Spirochaetales/classificação , Actinobacteria/classificação , Actinobacteria/genética , Adulto , Idoso , Bactérias/classificação , Bactérias/genética , Primers do DNA , DNA Bacteriano/análise , Eletroforese em Gel de Poliacrilamida , Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Pessoa de Meia-Idade , Doenças Periapicais/microbiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Spirochaetales/genética , Infecções por Spirochaetales/microbiologiaRESUMO
Olavius crassitunicatus is a small symbiont-bearing worm that occurs at high abundance in oxygen-deficient sediments in the East Pacific Ocean. Using comparative 16S rRNA sequence analysis and fluorescence in situ hybridization, we examined the diversity and phylogeny of bacterial symbionts in two geographically distant O. crassitunicatus populations (separated by 385 km) on the Peru margin (water depth, approximately 300 m). Five distinct bacterial phylotypes co-occurred in all specimens from both sites: two members of the gamma-Proteobacteria (Gamma 1 and 2 symbionts), two members of the delta-Proteobacteria (Delta 1 and 2 symbionts), and one spirochete. A sixth phylotype belonging to the delta-Proteobacteria (Delta 3 symbiont) was found in only one of the two host populations. Three of the O. crassitunicatus bacterial phylotypes are closely related to symbionts of other gutless oligochaete species; the Gamma 1 phylotype is closely related to sulfide-oxidizing symbionts of Olavius algarvensis, Olavius loisae, and Inanidrilus leukodermatus, the Delta 1 phylotype is closely related to sulfate-reducing symbionts of O. algarvensis, and the spirochete is closely related to spirochetal symbionts of O. loisae. In contrast, the Gamma 2 phylotype and the Delta 2 and 3 phylotypes belong to novel lineages that are not related to other bacterial symbionts. Such a phylogenetically diverse yet highly specific and stable association in which multiple bacterial phylotypes coexist within a single host has not been described previously for marine invertebrates.
Assuntos
Oligoquetos/metabolismo , Oligoquetos/microbiologia , Proteobactérias/isolamento & purificação , Spirochaetales/isolamento & purificação , Animais , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/genética , Deltaproteobacteria/classificação , Deltaproteobacteria/genética , Deltaproteobacteria/isolamento & purificação , Deltaproteobacteria/metabolismo , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/metabolismo , Biblioteca Gênica , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Oxirredução , Oceano Pacífico , Peru , Filogenia , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/metabolismo , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Spirochaetales/classificação , Spirochaetales/genética , Spirochaetales/metabolismo , Sulfatos/metabolismo , Sulfetos/metabolismo , SimbioseRESUMO
La información en cada uno de los 21 capítulos de este texto ha sido revisada con todo cuidado. Desde la publicación de la cuarta edición se han producido numerosos adelantos en la clasificación y nomenclatura taxonómica de los microorganismos de importancia clínica, y por eso han sido evaluados, revisados y actualizados centenares de nuevos métodos para el aislamiento e identificación de un conjunto de microorganismos siempre creciente. es muy importante destacar que en este texto se ha mantenido un enfoque centralizado en las propiedades bioquímicas y fisiológicas únicas de cada familia, género y especie de microorganismos clínicamente relevantes(AU)
Assuntos
Humanos , Masculino , Feminino , Bactérias/classificação , Microbiologia/história , Spirochaetales/classificação , MicrobiologiaRESUMO
Inocula from organic-rich black muds immediately underlying intertidal laminated microbial mats dominated by Microcoleus chthonoplastes yielded large, variable diameter spirochetes. These unusual spirochetes, previously reported only from the Alfacs Peninsula at the delta of the Ebro river in northeast Spain, contain striking arrays of cytoplasmic granules packed into their protoplasmic cylinders. On several occasions, both in summer and winter, the huge spirochetes were recognized in samples from mats growing in the Sippewissett salt marsh at Woods Hole Massachusetts. They were also seen in similar samples from microbial mats at North Pond, Laguna Figueroa, Baja California Norte, Mexico. The identity of these spirochetes was confirmed by electron microscopy: number and disposition of flagella, composite structure, measurements of their distinctive cytoplasmic granules. The granules, larger, more conspicuous and present in addition to ribosomes, are hypothesized to contain ATPases. As culture conditions worsen, these spirochetes retract into membrane-bounded round bodies in which they form refractile inclusions. From morphology and behavior we conclude the North American spirochetes from both Atlantic and Pacific intertidal microbial mats are indistinguishable from those at the delta of the Ebro river. We conclude a cosmopolitan distribution for Spirosymplokos deltaeiberi.
Assuntos
Microbiologia do Solo , Spirochaetales/isolamento & purificação , Massachusetts , México , Microscopia Eletrônica , Estações do Ano , Spirochaetales/classificação , Spirochaetales/ultraestruturaRESUMO
The essential GroEL proteins represent a subset of molecular chaperones ubiquitously distributed among species of the eubacterial lineage, as well as in eukaryote organelles. We employed these highly conserved proteins to infer eubacterial phylogenies. GroEL from the species analyzed clustered in distinct groups in evolutionary trees drawn by either the distance or the parsimony method, which were in general agreement with those found by 16S rRNA comparisons (i.e., proteobacteria, chlamydiae, bacteroids, spirochetes, firmicutes [gram-positive bacteria], and cyanobacteria-chloroplasts). Moreover, the analysis indicated specific relationships between some of the aforementioned groups which appeared not to be clearly defined or controversial in rRNA-based phylogenetic studies. For instance, a monophyletic origin for the low-G+C and high-G+C subgroups among the firmicutes, as well as their specific relationship to the cyanobacteria-chloroplasts, was inferred. The general observations suggest that GroEL proteins provide valuable evolutionary tools for defining evolutionary relationships among the eubacterial lineage of life.
Assuntos
Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/genética , Evolução Biológica , Proteínas de Choque Térmico/genética , Bactérias/química , Composição de Bases , Chaperonina 60 , Chlamydia/classificação , Chlamydia/genética , Cianobactérias/classificação , Cianobactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Helicobacter pylori/classificação , Helicobacter pylori/genética , Filogenia , Porphyromonas gingivalis/classificação , Porphyromonas gingivalis/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Spirochaetales/classificação , Spirochaetales/genéticaRESUMO
Large (up to 100 micrometers long), loosely coiled, free-living spirochetes with variable diameters (from 0.4 to 3 micrometers in the same cell) were seen at least 40 times between August 1990 and January 1993. These spirochetes were observed in mud water and enrichment media from highly specific habitats in intertidal evaporite flats at three disjunct localities, one in Spain and two in Mexico. All three are sites of commercial saltworks. Associated with Microcoleus chthonoplastes the large spirochetes from Spain display phototaxis and a composite organization. Shorter and smaller-diameter spirochetes are seen inside both healthy and spent periplasm of larger ones. Small spirochetes attached to large ones have been observed live. From two to twelve spirochete protoplasmic cylinders were seen inside a single common outer membrane. A distinctive granulated cytoplasm in which the granules are of similar diameter (20-32 nanometers) to that of the flagella (26 nanometers) was present. Granule diameters were measured in thin section and in negatively-stained whole-mount preparations. Based on their ultrastructure, large size, variable diameter, number of flagella (3 to 6), and phototactic behavior these unique spirochetes are formally named Spirosymplokos deltaeiberi. Under anoxic (or low oxygen) conditions they formed blooms in mixed culture in media selective for spirochetes. Cellobiose was the major carbon source in 80% seawater, the antibiotic rifampicin was added, mat from the original field site was present and tubes were incubated in the light at from 18-31 degrees C. Within 1-2 weeks populations of the large spirochete developed at 25 degrees C but they could not be transferred to fresh medium.
Assuntos
Sedimentos Geológicos/microbiologia , Spirochaetales/classificação , Microbiologia Ambiental , México , Microscopia Eletrônica , Água do Mar , Espanha , Spirochaetales/fisiologia , Spirochaetales/ultraestrutura , Microbiologia da ÁguaRESUMO
Spirochetes were found in the lower anoxiphototrophic layer of a stratified microbial mat (North Pond, Laguna Figueroa, Baja California, Mexico). Ultra-structural analysis of thin sections of field samples revealed spirochetes approximately 0.25 micrometer in diameter with 10 or more periplasmic flagella, leading to the interpretation that these spirochetes bear 10 flagellar insertions on each end. Morphometric study showed these free-living spirochetes greatly resemble certain symbiotic ones, i.e., Borrelia and certain termite spirochetes, the transverse sections of which are presented here. The ultrastructure of this spirochete also resembles Hollandina and Diplocalyx (spirochetes symbiotic in arthropods) more than it does Spirochaeta, the well known genus of mud-dwelling spirochetes. The new spirochete was detected in mat material collected both in 1985 and in 1987. Unique morphology (i.e., conspicuous outer coat of inner membrane, large number of periplasmic flagella) and ecology prompt us to name a new free-living spirochete.