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At least 19 recordsLinked to original sources
PubMed1992

Isolation of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) from Ixodes scapularis and Dermacentor albipictus ticks (Acari: Ixodidae) in Oklahoma.

Borrelia burgdorferi was isolated from Ixodes scapularis Say and Dermacentor albipictus Packard that were removed as partially fed adults from white-tailed deer, Odocoileus virginianus Zimmermann, in Oklahoma. Isolation in media was accomplished only after homogenates of pooled field-collected ticks were inoculated into laboratory-reared Peromyscus leucopus and reisolated from the urinary bladder into BSK II media. Both isolates were confirmed by western blot analysis and reactivity with monoclonal antibody H5332. These are the first reported isolates of B. burgdorferi from Oklahoma from these two tick species and are the first isolates from ticks from the south-central United States that were infective for laboratory-reared P. leucopus.

Animals↗
PubMed1992

Attempted transmission of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) (JDI strain) by Ixodes scapularis (Acari: Ixodidae), Dermacentor variabilis, and Amblyomma americanum.

Laboratory-reared Ixodes scapularis Say, Amblyomma americanum (L.), and Dermacentor variabilis (Say) were fed on New Zealand white rabbits experimentally infected with Borrelia burgdorferi (JDI strain). At repletion, spirochetes could be detected by dark-field microscopy only in I. scapularis. Acquisition rates were 18 and 21%. When previously exposed nymphs of each species were fed on susceptible rabbits, I. scapularis was the only tick of the three species that transmitted B. burgdorferi. When a single rabbit was experimentally infected with B. burgdorferi and infested at 7-d intervals with I. scapularis, A. americanum, D. variabilis, and a second time with I. scapularis, B. burgdorferi was detected again only in cultures from the two groups of I. scapularis. When molted nymphs from each tick species were allowed to feed on susceptible rabbits, spirochetes again were isolated only at necropsy from the rabbits on which the two groups of I. scapularis fed.

Animals↗
PubMed1974

Lipids of the Spirochaetales: comparison of the lipids of several members of the genera Spirochaeta, Treponema, and Leptospira.

The lipid compositions of 17 spirochetes belonging to the genera Spirochaeta and Treponema were investigated and compared with data previously derived from 11 strains of Leptospira. The lipid compositions and lipid metabolism of any of these genera is sufficiently different to be characteristic of that genus and to differentiate it from the other two genera. Members of the genus Leptospira are characterized by their ability to beta-oxidize long chain fatty acids as their major carbon and energy source. With few exceptions, they are incapable of synthesizing fatty acids de novo. The major phospholipid found was phosphatidyl ethanolamine. No glycolipid or phosphatidyl choline was found in these organisms. Members of the genus Treponema studied were incapable of beta-oxidation as well as de novo synthesis of fatty acids. Phosphatidyl choline is the major phospholipid of this genus. The glycolipid, monogalactosyl diglyceride, is a major component of the Treponema. Members of the Spirochaeta did synthesize fatty acids de novo. Although these spirochetes contain a monoglycosyl diglyceride, the hexose content of the glycolipid varied from species to species. Neither phosphatidyl ethanolamine nor phosphatidyl choline was found in the Spirochaeta.

Chromatography, Gas↗
PubMed1992

Cell wall-less, free-living spirochetes in Antarctica.

The phylogeny of an Antarctic, cell wall-less, bacterial strain was determined by sequencing PCR amplified 16S rDNA, and comparison of the sequence with other bacterial 16S rRNA sequences available in databanks. Although the strain was phenotypically very similar to members of the genus Anaeroplasma, phylogenetic analyses showed it was a member of the order Spirochaetales. Until now, the order was one of the few bacterial orders in which phylogeny was reflected in a uniform morphology of its members. The viability of wall-less cells in cultures of spirochetes and spirochetal infective material warrants reinvestigation.

Antarctic Regions↗
PubMed1989

[Classification of spirochetes infecting man].

The systematics od spirochetes must from now own fulfil the genomic criteria recently laid down. Formerly, these parasites were classified on the basis of various phenotypic features, among which the pathogenicity and epidemiological criteria played the predominant role. At present, the order of Spirochaetales is divided into two families: Spirochaetaceae and Leptospiraceae. Two of the four genera of Spirochaetaceae, Treponema and Borrelia, include species that are pathogenic to man. Among Leptospiraceae, only one genus, Leptospira, has pathogenic species. The phenotypic characteristics of the various taxons are detailed, the role of each actor (causative agent, vector, reservoir) in the main pathological complexes and the progress of genotypic studies are briefly described.

Humans↗
PubMed1991

Borrelia burgdorferi: another cause of foodborne illness?

Borrelia burgdorferi was identified as the etiological agent of Lyme disease in 1982. This Gram-negative spirochete is classified in the order Spirochaetales and the family Spirochaetaceae. The pathogen is fastidious, microaerophilic, mesophilic and metabolises glucose through the Embden-Meyerhof pathway. A generation time of 11 to 12 h at 37 degrees C in Barbour-Stoenner-Kelly medium has been reported. Lyme disease, named after Lyme in Connecticut, is distributed globally. It is the most commonly reported vector-borne disease in the United States, where the incidence is highest in the eastern and midwestern states. Since establishment of national surveillance in 1982, there has been a nine-fold increase in the number of cases reported to the U.S. Centers for Disease Control. The deer tick of the genus Ixodes is the primary vector of Lyme borreliosis. The tick may become infected with B. burgdorferi, by feeding on an infected host, at any point in its 2-year life cycle which involves larval, nymphal and adult stages. The infection rate in deer ticks may be as high as 40% in endemic areas. The primary vertebrate reservoirs for Ixodes are the white-footed mouse (Peromyscus leucopus) and the white-tailed deer (Odocopileus virginianus). Dairy cattle and other food animals can be infected with B. burgdorferi and hence some raw foods of animal origin might be contaminated with the pathogen. Recent findings indicate that the pathogen may be transmitted orally to laboratory animals, without an arthropod vector. Thus, the possibility exists that Lyme disease can be a food infection. In humans, the symptoms of Lyme disease, which manifest themselves days to years after the onset of infection, may involve the skin, cardiac, nervous and/or muscular systems, and so misdiagnosis can occur.

Animals↗
PubMed1990

Cloning of genes required for amino acid biosynthesis from Leptospira interrogans serovar icterohaemorrhagiae.

Leptospira interrogans belongs to a large family of important pathogens, which is part of the order Spirochaetales, a distinct group of eubacteria. In order to obtain a better understanding of the genetic organization of this species, we have constructed a DNA library of the serovar icterohaemorrhagiae, using the Escherichia coli vector pUC13. We have isolated Leptospira DNA fragments containing the genetic information required to complement strains of E. coli with defects in proline and leucine biosynthesis. While a 3.9 kb fragment which complemented proA also complemented proB, a 15 kb fragment complementing leuB could not complement other leu mutations. The L. interrogans origin of the cloned DNA fragments was confirmed by DNA-DNA hybridization. The hydridization was specific to the pathogenic species and was not seen with the saprophytic species L. biflexa.

Amino Acids↗
PubMed1988

Nucleotide sequence analysis of a gene cloned from Leptospira biflexa serovar patoc which complements an argE defect in Escherichia coli.

The genus Leptospira, as a member of the order Spirochaetales, forms one of the most ancient evolutionary branches of the eubacteria. These spirochetes are morphologically and physiologically different from most eubacteria, and little is known about Leptospira genetics. In this communication, we report the first nucleotide sequence of a Leptospira gene. A gene which complements an argE mutation in Escherichia coli was isolated from a plasmid-based genomic library composed of Leptospira biflexa serovar patoc DNA. The functional region for the complementing activity was localized by transposon mutagenesis and restriction enzyme mapping and by subcloning. Nucleotide sequence analysis indicated a single open reading frame within the region containing argE complementing activity. The size of the predicted protein, 31,071 daltons, was in excellent agreement with data obtained from coupled transcription-translation reactions primed with cloned L. biflexa DNA. One surprising result was that the predicted amino acid sequence of this protein closely resembles portions of the beta' subunits of RNA polymerases from bacteria and chloroplasts.

Amino Acid Sequence↗
PubMed1989

Unusual in vitro formation of cyst-like structures associated with human intestinal spirochaetosis.

Spirochaetes were isolated from rectal biopsies of three patients and successfully cultured. Enzymatic reactions and electron microscopy revealed spirochaetes resembling Brachyspira aalborgi. Examination of ultrathin sections of centrifugates of cultured spirochaetes yielded unusual cyst-like structures with an outer double membrane containing spirochaetes in different developmental stages. The protoplasmic cylinders seemed to originate from a large electron-dense focus in the cyst-like structures. The axial fibrils occurred as loosely distributed solitary structures in the cyst-like structures. Cysts were not found in the biopsy tissue. The encystment of the spirochaetes could be related to their protection, multiplication, spread and transmission.

Colitis↗
PubMed1985

Intestinal spirochetosis of the vermiform appendix.

A series of 681 surgically removed appendices were examined for spirochetes. Five hundred seventy-four appendices were removed because of suspected acute appendicitis; the rest were removed per occasionem. One hundred six of the former were histologically normal, whereas 421 showed acute appendicitis. The remaining 47 specimens showed a variety of other pathological conditions, for example, tumors and diverticula. Spirochetes were found in 13 (12.3%) of the appendices removed from patients clinically suspected to suffer from acute appendicitis, but whose appendices were otherwise histologically normal (pseudoappendicitis). Only 3 patients (0.7%) with histologically confirmed acute appendicitis (p less than 0.05) did show spirochetes in their appendices. Of the 107 patients who had their appendices removed per occasionem, 2 patients (1.9%) had spirochetosis (p less than 0.05). The ultrastructure of the spirochetes obtained from appendices with spirochetosis was studied by means of negative staining and ultrathin sectioning. The morphology of these spirochetes was very similar to that of Brachyspira aalborgi, a spirochete recently isolated from rectal biopsy specimens obtained from patients with colorectal spirochetosis.

Appendectomy↗