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PubMed1974

Localization of spirochetes with the structural characteristics of Treponema hyodysenteriae in the lesions of swine dysentery.

The large intestines of pigs with swine dysentery were examined by phase, light, and electron microscopy at intervals up to 11 days after oral inoculation with mucosal scrapings from infected pigs. Large spirochetes with the structural characteristics of Treponema hyodysenteriae were found only in infected pigs and were first observed in small numbers in the lumen of the large intestine 2 days after inoculation. Numerous large spirochetes were present on the luminal surface and in mucosal crypts as lesions developed. Degenerative changes were first observed in the apical portion of epithelial cells in close contact with large spirochetes. These large spirochetes were found intact in goblet cells and epithelial cells in the early stages of the disease and were numerous within degenerating epithelial cells as lesions became more advanced. Invasion beyond the lamina propria was not detected. These observations demonstrated the relationship between pathogenic large spirochetes and the mucosa of the large intestine in a specific disease, swine dysentery.

Animals↗
PubMed1972

Shape of Treponema pallidum.

Treponema pallidum was found to be not helical, but a flat wave twisted into one to five different planes per cell.

Bacteriological Techniques↗
PubMed1998

Structure and expression of the FlaA periplasmic flagellar protein of Borrelia burgdorferi.

The spirochete which causes Lyme disease, Borrelia burgdorferi, has many features common to other spirochete species. Outermost is a membrane sheath, and within this sheath are the cell cylinder and periplasmic flagella (PFs). The PFs are subterminally attached to the cell cylinder and overlap in the center of the cell. Most descriptions of the B. burgdorferi flagellar filaments indicate that these organelles consist of only one flagellin protein (FlaB). In contrast, the PFs from other spirochete species are comprised of an outer layer of FlaA and a core of FlaB. We recently found that a flaA homolog was expressed in B. burgdorferi and that it mapped in a fla/che operon. These results led us to analyze the PFs and FlaA of B. burgdorferi in detail. Using Triton X-100 to remove the outer membrane and isolate the PFs, we found that the 38.0-kDa FlaA protein purified with the PFs in association with the 41.0-kDa FlaB protein. On the other hand, purifying the PFs by using Sarkosyl resulted in no FlaA in the isolated PFs. Sarkosyl has been used by others to purify B. burgdorferi PFs, and our results explain in part their failure to find FlaA. Unlike other spirochetes, B. burgdorferi FlaA was expressed at a lower level than FlaB. In characterizing FlaA, we found that it was posttranslationally modified by glycosylation, and thus it resembles its counterpart from Serpulina hyodysenteriae. We also tested if FlaA was synthesized in a spontaneously occurring PF mutant of B. burgdorferi (HB19Fla-). Although this mutant still synthesized flaA message in amounts similar to the wild-type amounts, it failed to synthesize FlaA protein. These results suggest that, in agreement with data found for FlaB and other spirochete flagellar proteins, FlaA is likely to be regulated on the translational level. Western blot analysis using Treponema pallidum anti-FlaA serum indicated that FlaA was antigenically well conserved in several spirochete species. Taken together, the results indicate that both FlaA and FlaB comprise the PFs of B. burgdorferi and that they are regulated differently from flagellin proteins of other bacteria.

Borrelia↗
PubMed1961

Influence of osmotic pressure on the morphology of the Reiter treponeme.

Hardy, Paul H., Jr. (Johns Hopkins University, Baltimore, Md.) and E. Ellen Nell. Influence of osmotic pressure on the morphology of the Reiter treponeme. J. Bacteriol. 82: 967-978. 1961.-Spherical bodies similar to those that develop spontaneously in cultures of treponemes, and which have been considered by many investigators to represent one stage in a complex life cycle of these organisms, can be produced rapidly with the Reiter treponeme by merely altering the medium in which the organisms are suspended. Osmotic pressure appears to be the major factor responsible for this effect, as shown by the observation that treponemes suspended in NaCl solutions of 0.15 to 0.10 m retain their spirochetal morphology, whereas organisms suspended in more dilute salt solutions rapidly become spherical. Moreover, the concentration of salt appears to influence both the rate and extent of sphere formation. Further evidence that osmotic pressure is primarily involved is demonstrated by the selectivity of the conditions under which spheres form. Treponemes suspended in various 0.3 osmolal solutions either retain their spiral shape or form spheres, depending upon the nature of the solute. Viability studies of suspensions containing predominantly spherical forms, which have developed spontaneously or have been artificially induced, have failed to produce evidence that the resulting growth of treponemes came from the spheres. It is concluded, therefore, that the naturally occurring spheres probably arise as the result of an osmotic imbalance which develops between the cells and their environment, and that the spheres represent degenerative forms rather than an intermediate stage in a life cycle.

Osmolar Concentration↗
PubMed1963

MORPHOLOGY OF TREPONEMA MICRODENTIUM AS REVEALED BY ELECTRON MICROSCOPY OF ULTRATHIN SECTIONS.

Listgarten, M. A. (Harvard School of Dental Medicine and Forsyth Dental Infirmary, Boston, Mass.), W. J. Loesche, and S. S. Socransky. Morphology of Treponema microdentium as revealed by electron microscopy of ultrathin sections. J. Bacteriol. 85:932-939. 1963.-Broth cultures of a strain of Treponema microdentium were harvested on Millipore filters, fixed in osmic acid, and sectioned for electron microscopy. The sections revealed that the spirochetes had an axial filament, made up of two fibrils approximately 150 A in diameter, which was situated between an external envelope approximately 140 A in thickness and a protoplasmic cylinder. The protoplasmic cylinder had a cross-sectional diameter of 100 to 200 mmu, and was surrounded by a double "membrane" consisting of two 40-A electron-dense structures separated by a 45-A space. Cross-sections of spirochetal "granules" revealed that the limiting membrane was continuous with the outer envelope of the spirochetes, and surrounded the protoplasmic cylinder and axial filament.

Cross-Sectional Studies↗
PubMed1964

ELECTRON MICROSCOPY OF AXIAL FIBRILS, OUTER ENVELOPE, AND CELL DIVISION OF CERTAIN ORAL SPIROCHETES.

Listgarten, M. A. (Harvard School of Dental Medicine and Forsyth Dental Center, Boston, Mass.), and S. S. Socransky. Electron microscopy of axial fibrils, outer envelope, and cell division of certain oral spirochetes. J. Bacteriol. 88:1087-1103. 1964.-The ultrastructure of axial fibrils and outer envelopes of a number of oral spirochetes was studied in thin sections and by negative contrast. The axial fibrils measured 150 to 200 A in diameter. Only one end of each fibril was inserted subterminally into the protoplasmic cylinder by means of a 400 A wide disc. The free ends of fibrils inserted near one end of the cylinder extended toward, and overlapped in close apposition, the free ends of fibrils inserted at the other end. In thin sections, some axial fibrils showed a substructure, suggestive of a dense central core. The outer envelopes of most spirochetes appeared to consist of 80 A wide polygonal structural subunits. However, in one large spirochete, the outer envelope demonstrated a "pin-striped" pattern. Cell division in a pure culture of Treponema microdentium was studied by negative contrast. Results suggested that this organism divides by transverse fission, the outer envelope being last to divide. During the course of division, new axial fibrils appeared to originate on either side of the point of constriction of the protoplasmic cylinder. Flagellalike extensions which were found in rapidly dividing organisms were due to protruding axial fibrils, and appeared to be the result of cell division. Some evidence is presented to support the concept of a homologous origin for axial fibrils and flagella.

Cell Division↗
PubMed1968

Spirochete from the rabbit tick, Haemaphysalis leporispalustris (Packard). I. Isolation and preliminary characterization.

An unidentified spirochete, referred to as the 277F agent, was isolated from Haemaphysalis leporispalustris ticks from two cottontail rabbits by inoculation of the tick suspension into embryonated chicken eggs. Because of its minute width (0.1 mu), the organism was difficult to see when stained by the Giemsa method, but was readily demonstrated by silver impregnation or fluorescent-antibody procedures. In dark-field microscopy, the spirochetes appeared uniformly and rather tightly coiled, and exhibited typical corkscrewlike motility. After yolk-sac inoculation, the agent was highly lethal for chick embryos and was recovered in large quantity from several embryonic tissues and fluids. It could also be maintained in nonfertile eggs and in an enriched liquid medium. This previously undescribed spirochete could pass through Berkefeld N but not Seitz EK filters. It was relatively resistant to heat and to penicillin or sulfadiazine, but was markedly inhibited by streptomycin, broad-spectrum antibiotics, and homologous neutralizing antiserum. Of several species of animals tested for susceptibility to this spirochete, only the snowshoe hare gave evidence of infection.

Animals↗
PubMed2003

Analysis of the ability of spirochete species associated with relapsing fever, avian borreliosis, and epizootic bovine abortion to bind factor H and cleave c3b.

Some Borrelia species associated with Lyme disease bind the complement-regulatory protein factor H (fH), a process that may aid in immune evasion. In this report we demonstrate that some Borrelia species associated with relapsing fever bind fH, but not those associated with avian borreliosis and epizootic bovine abortion. Cell-bound fH was also found to mediate cleavage of exogenously supplied human C3b, demonstrating the biological relevance of fH binding and its possible importance in the pathogenesis of the relapsing-fever spirochetes.

Abortion, Veterinary↗
PubMed2000

Aminoacyl-tRNA synthetases, the genetic code, and the evolutionary process.

The aminoacyl-tRNA synthetases (AARSs) and their relationship to the genetic code are examined from the evolutionary perspective. Despite a loose correlation between codon assignments and AARS evolutionary relationships, the code is far too highly structured to have been ordered merely through the evolutionary wanderings of these enzymes. Nevertheless, the AARSs are very informative about the evolutionary process. Examination of the phylogenetic trees for each of the AARSs reveals the following. (i) Their evolutionary relationships mostly conform to established organismal phylogeny: a strong distinction exists between bacterial- and archaeal-type AARSs. (ii) Although the evolutionary profiles of the individual AARSs might be expected to be similar in general respects, they are not. It is argued that these differences in profiles reflect the stages in the evolutionary process when the taxonomic distributions of the individual AARSs became fixed, not the nature of the individual enzymes. (iii) Horizontal transfer of AARS genes between Bacteria and Archaea is asymmetric: transfer of archaeal AARSs to the Bacteria is more prevalent than the reverse, which is seen only for the "gemini group. " (iv) The most far-ranging transfers of AARS genes have tended to occur in the distant evolutionary past, before or during formation of the primary organismal domains. These findings are also used to refine the theory that at the evolutionary stage represented by the root of the universal phylogenetic tree, cells were far more primitive than their modern counterparts and thus exchanged genetic material in far less restricted ways, in effect evolving in a communal sense.

Amino Acids↗
PubMed1971

Intestinal spirochaetosis.

An abnormal condition of the large intestine is described in which the surface epithelium is infested by short spirochaetes. Diagnosis can be made by light microscopy. A review of 14 cases diagnosed by rectal biopsy and 62 cases involving the appendix shows no consistent symptom complex. The possible significance is discussed.

Adult↗
PubMed2005

Pseudospirochaetosis of the urinary bladder.

This report describes an elderly patient with urinary symptoms who showed surface colonisation of the transitional mucosa of the bladder by an unusual haematoxophilic microorganism superficially resembling the "blue fuzz" seen in colonic biopsies showing intestinal spirochaetosis. Special stains showed that the organisms were Gram and Giemsa positive, weakly argyrophilic, and Ziehl-Nielsen negative. Immunostains were negative for Helicobacter pylori and electron microscopy revealed curious curved bodies, which were difficult to classify. Therefore, this condition was described as pseudospirochaetosis of the urinary bladder. The urinary symptoms regressed on treatment with ciprofloxacin. The clinicopathological relevance of these findings is discussed in the report.

Aged↗
PubMed1981

Isolation of intestinal spirochaetes from homosexuals.

Spirochaetes were isolated from rectal swabs of two homosexuals and the faeces of a third, using simple isolation techniques not previously applied to specimens of this type. The ease of culture of these organisms will enable their distribution and pathogenicity to be studied, particularly in relation to their significance in homosexuals.

Adult↗