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PubMed2000

Complete genome sequence of the alkaliphilic bacterium Bacillus halodurans and genomic sequence comparison with Bacillus subtilis.

The 4 202 353 bp genome of the alkaliphilic bacterium Bacillus halodurans C-125 contains 4066 predicted protein coding sequences (CDSs), 2141 (52.7%) of which have functional assignments, 1182 (29%) of which are conserved CDSs with unknown function and 743 (18. 3%) of which have no match to any protein database. Among the total CDSs, 8.8% match sequences of proteins found only in Bacillus subtilis and 66.7% are widely conserved in comparison with the proteins of various organisms, including B.subtilis. The B. halodurans genome contains 112 transposase genes, indicating that transposases have played an important evolutionary role in horizontal gene transfer and also in internal genetic rearrangement in the genome. Strain C-125 lacks some of the necessary genes for competence, such as comS, srfA and rapC, supporting the fact that competence has not been demonstrated experimentally in C-125. There is no paralog of tupA, encoding teichuronopeptide, which contributes to alkaliphily, in the C-125 genome and an ortholog of tupA cannot be found in the B.subtilis genome. Out of 11 sigma factors which belong to the extracytoplasmic function family, 10 are unique to B. halodurans, suggesting that they may have a role in the special mechanism of adaptation to an alkaline environment.

ATP-Binding Cassette Transporters↗
PubMed1993

Characterization of Bacillus brevis with descriptions of Bacillus migulanus sp. nov., Bacillus choshinensis sp. nov., Bacillus parabrevis sp. nov., and Bacillus galactophilus sp. nov.

Thirty-five Bacillus brevis strains obtained from culture collections, including protein-producing isolates, were taxonomically studied by using numerical analysis, DNA base composition, and DNA-DNA hybridization. Six DNA relatedness groups were represented, and these groups correlated well with clusters based on the numerical analysis. The B. brevis strains were separated into B. brevis sensu stricto, four new species, and an unidentified species of the genus Bacillus. Bacillus migulanus sp. nov., Bacillus choshinensis sp. nov., Bacillus parabrevis sp. nov., and Bacillus galactophilus sp. nov. are proposed.

Bacillus↗
PubMed1993

Herbidospora gen. nov., a new genus of the family Streptosporangiaceae Goodfellow et al. 1990.

Eight actinomycete strains originally isolated from soil and plant samples were studied to determine their taxonomic status. All isolates produced branching substrate mycelia, but no distinct aerial hyphae. Relatively short chains of nonmotile spores (10 to 30 spores per chain) were borne on the tips of sporophores arising directly from the agar surface. The chemotaxonomic characteristics of the isolates, with the exception of the menaquinone profile, coincided with those of members of the family Streptosporangiaceae Goodfellow, Stanton, Simpson, and Minnikin 1990. Furthermore, the results of a phylogenetic analysis performed with 5S rRNA support the conclusion that the isolates should be classified in this family. The isolates differed from members of the constituent genera of the Streptosporangiaceae in morphological characteristics and menaquinone composition. Therefore, we propose a new genus for the strains, Herbidospora. The type species and type strain are Herbidospora cretacea sp. nov. and strain K-319 (= JCM 8553), respectively.

Actinomycetales↗
PubMed1998

Staphylococcus succinus sp. nov., isolated from Dominican amber.

Two bacterial isolates, designated AMG-D1T and AMG-D2, were recovered from 25-35-million-year-old Dominican amber. AMG-D1T and AMG-D2 biochemically most closely resemble Staphylococcus xylosus; they differ physiologically from other staphylococci. Fatty acid analysis and comparisons with extensive databases were unable to show relatedness to any specific taxon. Moreover, AMG-D1T and AMG-D2 contain tuberculostearic acid and meso-diaminopimelic acid, characteristic of the G + C-rich coryneform bacteria, as opposed to L-lysine characteristic of staphylococci. AMG-D1T and AMG-D2 have a G + C ratio of 35 mol%. Phylogenetic analysis with the 16S rRNA gene indicated that AMG-D1T and AMG-D2 were most closely related to Staphylococcus equorum, S. xylosus, Staphylococcus saprophyticus and other novobiocin-resistant staphylococci. Stringent DNA-DNA hybridization studies with AMG-D1T revealed similarities of 38% with S. equorum, 23% with S. xylosus and 6% with S. saprophyticus. The results indicate that AMG-D1T and AMG-D2 represent a novel species, which was named Staphylococcus succinus sp. nov. The type strain of the new species is AMG-D1 (ATCC 700337).

Amber↗
PubMed1988

Taxonomic studies on Brochothrix, Erysipelothrix, Listeria and atypical lactobacilli.

One hundred and eighty-seven strains of listeriae, atypical lactobacilli, Brochothrix, Erysipelothrix and related Gram-positive bacteria were tested for 140 characters based on morphology, physiology and biochemistry. Computer analyses of the data resulted in the recovery of 20 phenons. Representative strains were examined for cytochrome content, cell wall, fatty acid and isoprenoid quinone composition and the G + C content of the DNA. The results indicate that the species Listeria monocytogenes, L. innocua and L. ivanovii are phenotypically very similar. L. grayi and L. murrayi are more distinct from these but are so similar to each other that L. murrayi should be regarded as a subspecies of L. grayi. Some of the atypical lactobacilli studied are members of the genus Brochothrix; the others probably represent four distinct species in a new genus.

Base Composition↗
PubMed1986

Effects of Lactobacillus casei on Pseudomonas aeruginosa infection in normal and dexamethasone-treated mice.

A single intraperitoneal injection of Lactobacillus casei YIT 0003 into normal or dexamethasone-treated mice led to nonspecific resistance against intraperitoneal challenge with lethal doses of Pseudomonas aeruginosa PAO 3047. The enhanced resistance was retained for 14 days (P less than 0.05) after injection with living L. casei. In contrast, the statistically significant duration of the enhanced resistance in mice treated intraperitoneally with living L. acidophilus YIT 0075 was only 5 days. The in vivo killing activity of peritoneal exudate cells (PECs) against P. aeruginosa 5 and 7 days after intraperitoneal injection of living L. casei was significantly higher than in the case of PECs elicited by L. acidophilus. In the case of intravenous injection of heat-killed L. casei before intraperitoneal challenge with P. aeruginosa, there were no survivors in the late period after administration of L. casei. A high correlation existed between the patterns of in vivo killing of P. aeruginosa by PECs and survival rate of mice injected intravenously with heat-killed L. casei. The reduced in vivo killing activity of PECs from dexamethasone-treated mice against P. aeruginosa infection was also augmented by the intraperitoneal injection of heat-killed L. casei. These results indicate that L. casei possesses a resistance-enhancing capacity against P. aeruginosa infection in vivo. Differences in the duration of the enhanced resistance caused by L. casei and by L. acidophilus may be due to differences in chemical composition and/or physicochemical properties of the cell walls of the two kinds of bacteria.

Animals↗
PubMed1980

Distribution and characterization of kepone-resistant bacteria in the aquatic environment.

Effects of the chlorinated insecticide Kepone on the ecology of Chesapeake Bay and James River bacteria were studied. Kepone-resistant bacteria present in a given environment were found to reflect the degree of fecal and/or high organic pollution of the sampling sites, based on total numbers and generic composition of the populations of Kepone-resistant bacteria. The presence of Kepone-resistant bacteria was found to be correlated (alpha = 0.01) with total coliforms, fecal coliforms, and total aerobic viable heterotrophic bacteria, but not with Kepone concentration, since Kepone-resistant bacteria were present in locations where Kepone could not be detected by the analytical methods used in this study. Only gram-negative bacteria, predominantly Pseudomonas, Vibrio, and Aeromonas spp., were found to be resistant to >/=10 mug of Kepone per ml. Gram-positive bacteria, i.e., Bacillus and Corynebacterium spp., were generally sensitive to >/=0.1 mug of Kepone per ml. From results of cluster analysis of taxonomic data, we determined that characteristics of Kepone-resistant bacteria included: resistance to pesticides and heavy metals; degradation of oil; positive oxidase and catalase reactions; and nitrate reduction. From results of the ecological and taxonomic analyses, we conclude that Kepone resistance in estuarine bacteria is due to the physicochemical composition of the gram-negative cell wall and not prior exposure to Kepone. Therefore, the presence of Kepone-resistant bacteria cannot serve as an indicator of Kepone contamination in the aquatic environment where gram-negative bacteria are predominant.

Aeromonas↗
PubMed1995

Alterations in structure, chemistry, and biodegradability of grass lignocellulose treated with the white rot fungi Ceriporiopsis subvermispora and Cyathus stercoreus.

The white rot fungi Ceriporiopsis subvermispora FP-90031-sp and Cyathus stercoreus ATCC 36910 were evaluated for their ability to delignify Bermuda grass (Cynodon dactylon) stems and improve biodegradability. Compositional and structural alterations in plant cell walls effected by the fungi were determined by nuclear magnetic resonance spectroscopy, gas chromatography of alkali-treated residues, microspectrophotometry, and electron microscopy. Contaminating bacteria and fungi, which grew from unsterilized Bermuda grass stems, did not alter the improvement in grass biodegradability by either of the fungi from that of gas-sterilized stems. The biodegradation of stems by ruminal microorganisms, after treatment for 6 weeks with C. subvermispora or C. stercoreus, was improved by 29 to 32% and by 63 to 77%, respectively; dry weight losses caused by pretreatment with the fungi were about 20% over that in untreated, control stems. Both fungi preferentially removed aromatics to carbohydrates, and C. subvermispora removed proportionately more guaiacyl units than did C. stercoreus. Substantial amounts of ester-linked p-coumaric and ferulic acids were removed by both fungi, and about 23 and 41% of total aromatics (determined after 4 M NaOH direct treatment) were removed from the plant biomass after incubation with C. subvermispora and C. stercoreus, respectively. UV absorption microspectrophotometry indicated that ester-linked phenolic acids were totally removed from the parenchyma cell walls, and these cells were readily and completely degraded by both fungi. However, aromatic constituents were only partially removed from the more recalcitrant sclerenchyma cell walls, resulting in variation in electron density and random digestion pits after incubation with fiber-degrading bacteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Basidiomycota↗
PubMed1988

Legionella pneumophila serogroup Lansing 3 isolated from a patient with fatal pneumonia, and descriptions of L. pneumophila subsp. pneumophila subsp. nov., L. pneumophila subsp. fraseri subsp. nov., and L. pneumophila subsp. pascullei subsp. nov.

Previous DNA relatedness and enzyme electrophoretic mobility studies indicated heterogeneity among strains of Legionella pneumophila serogroups 1, 4, 5, and Lansing 3 (a new, as yet unnumbered serogroup). In this study 60 L. pneumophila strains were studied by DNA hybridization (hydroxyapatite method) to assess their genomic relatedness. These strains were also studied biochemically and serologically to determine whether they formed one or more phenotypic groups. DNA relatedness studies identified three groups. DNA group 1 contained the type strain Philadelphia 1 and strains from serogroups 1 through 14 of L. pneumophila. The average relatedness of DNA group 1 strains was 88% at 60 degrees C with 1.1% divergence in related sequences and 85% at 75 degrees C. DNA group 2 contained strain Los Angeles 1, the reference strain of serogroup 4, and strains of serogroups 1, 4, 5, and Lansing 3, an unnumbered serogroup. Average relatedness of DNA group 2 strains was 84% at 60 degrees C with 0.7% divergence and 87% at 75 degrees C. Reciprocal relatedness of DNA groups 1 and 2 was approximately 67% at 60 degrees C with 6.0% divergence and 48% at 75 degrees C. DNA group 3 strains were in serogroup 5. They were 98% related at 60 degrees C with 0.5% divergence and 97% related at 75 degrees C. Reciprocal relatedness of DNA group 3 and DNA group 1 was approximately 74% at 60 degrees C with 5.3% divergence and 43% at 75 degrees C, and reciprocal relatedness of DNA groups 3 and 2 was 66% at 60 degrees C with 5.7% divergence and 55% at 75 degrees C. The DNA groups could not be separated biochemically or serologically or by cell wall fatty acid and isoprenoid quinone composition. Three subspecies of L. pneumophila are proposed to accommodate the three DNA groups: L. pneumophila subsp. pneumophila subsp. nov. for DNA group 1, L. pneumophila subsp. fraseri subsp. nov. for DNA group 2, and pneumophila subsp. pascullei subsp. nov. for DNA group 3.

DNA, Bacterial↗
PubMed1995

Bacillus oleronius sp.nov., a member of the hindgut flora of the termite Reticulitermes santonensis (Feytaud).

A new rod-shaped endospore-forming bacterium is described, which was isolated from the hindgut of the termite Reticulitermes santonensis (Feytaud). The isolate stains Gram negative and its DNA has a guanine-plus-cytosine content of 35 mol%. Despite the Gram-staining reaction, both biochemical and physiological features place the isolate in the genus Bacillus and indicate a phenotypic resemblance to the Bacillus firmus-lentus group of species. On the basis of comparative 16S rRNA analysis and some phenotypic features the isolate clearly represents a new species for which the name Bacillus oleronius is proposed. The type strain is Bacillus oleronius Rt 10 (DSM 9356).

Animals↗
PubMed1985

Further characterization including preliminary chemical analysis of antigen MLW1 from Mycobacterium leprae.

MLW1, an antigen preparation from Mycobacterium leprae previously shown to have a high content of M. leprae antigen No. 7 (ML7), was found to contain the typical cell wall constituents arabinose, galactose and mannose. The fatty acid composition of MLW1 was largely comparable to that of undisrupted cells. The capacity of MLW1 to stimulate lymphocytes was further studied. Good correlation was obtained between the in vitro lymphocyte responses to MLW1 and human-derived M. leprae, indicating similar specificity of the two antigen preparations in this test. The stimulatory activity of MLW1 was not significantly influenced by batch to batch variations, was well-preserved during storage and most of it was heat-stable. Attempts to remove the ML7 antigen indicate that this component plays a dominant role in inducing in vitro lymphocyte stimulation.

Antigens, Bacterial↗
PubMedDate not supplied

[Effect of conditions od Trichosporon pullulans culturing on the synthesis of immunomodulating glycoprotein].

An extracellular glycoprotein (GP) exhibiting immunomodulating activity produced by the yeast Trichosporon pullulans grown in a defined ethanol-containing medium differed substantially in its composition from that of the yeast cell walls: therefore, it cannot be considered a structural component of the cell walls. In batch culture, the greatest GP production (40 mg/l) occurred in the exponential phase of the yeast growth. Under continuous cultivation, in both chemostat and pH-auxostat regimes, the specific rate of GP synthesis (qGP) increased with the increasing specific growth rate (mu) and reached 1.55 mg/(g h) at mumax. Under limitation of the yeast growth by zinc qGP was three times lower than under nitrogen or iron limitation. The rate of GP production depended inversely on the oxygen concentration.

Adjuvants, Immunologic↗
PubMed1989

Immunopathology of experimental bronchiectasis.

In human bronchiectasis, the bronchial wall is the seat of abnormal mononuclear cell infiltration, which suggests the presence of a cell-mediated immune reaction. The histopathology of a recently devised animal model of experimental bronchiectasis resembles that of the human disease. We have investigated its immunohistology to validate the similarity to that of human bronchiectasis in order to provide a model for the study of cellular immune aspects of the pathogenesis of bronchiectasis. The immunohistology of the bronchial wall mononuclear cell population in experimental rat bronchiectasis was compared with that in control and normal rats. The control rats did not develop bronchiectasis, and the composition and distribution of mononuclear cells in the bronchial wall were similar to those of normal animals. In the rats developing bronchiectasis, there was infiltration of T lymphocytes, macrophages, and dendritic cells (as defined by monoclonal antibodies) in all compartments of the lung, particularly in the bronchial wall and around vessels. The bronchus-associated lymphoid tissue was disrupted by heavy infiltration of T cells, and follicular aggregates of T lymphocytes were seen deeper in the lung parenchyma. Expression of Ia antigen increased in the bronchial epithelium and in large numbers of mononuclear cells throughout the lung. These findings suggest that a cell-mediated immune response appears during the development of experimental bronchiectasis in this rat model. This cellular immune response is similar to that described in human bronchiectasis and may enable this animal model to be used in defining the role of cellular immunity in the pathogenesis of bronchiectasis.

Animals↗
PubMed2003

Secretory vesicle formation in the secretory cavity of glandular trichomes of Cannabis sativa L. (Cannabaceae).

The disc cell wall facing the secretory cavity in lipophilic glands of Cannabis was studied for origin and distribution of hyaline areas, secretory vesicles, fibrillar matrix and particulate material. Secretions evident as light areas in the disc cell cytoplasm pass through modified regions in the plasma membrane and appear as hyaline areas in the cell wall. Hyaline areas, surrounded with a filamentous outline, accumulate near the wall surface facing the secretory cavity where they fuse to form enlarged hyaline areas. Fibrillar matrix is related to and may originate from the dense outer layer of the plasma membrane. This matrix becomes distributed throughout the wall material and contributes in part to the composition of the surface feature of secretory vesicles. Thickening of the cell wall is associated with secretions from the disc cells that facilitates movement of hyaline areas, fibrillar matrix and other possible secretions through the wall to form secretory vesicles and intervesicular materials in the secretory cavity. The outer wall of disc cells in aggregate forms the basilar wall surface of the secretory cavity which facilitates the organization of secretory vesicles that fill the secretory cavity.

Animals↗
PubMed2005

Evidence for in vitro binding of pectin side chains to cellulose.

Pectins of varying structures were tested for their ability to interact with cellulose in comparison to the well-known adsorption of xyloglucan. Our results reveal that sugar beet (Beta vulgaris) and potato (Solanum tuberosum) pectins, which are rich in neutral sugar side chains, can bind in vitro to cellulose. The extent of binding varies with respect to the nature and structure of the side chains. Additionally, branched arabinans (Br-Arabinans) or debranched arabinans (Deb-Arabinans; isolated from sugar beet) and galactans (isolated from potato) were shown bind to cellulose microfibrils. The adsorption of Br-Arabinan and galactan was lower than that of Deb-Arabinan. The maximum adsorption affinity of Deb-Arabinan to cellulose was comparable to that of xyloglucan. The study of sugar beet and potato alkali-treated cell walls supports the hypothesis of pectin-cellulose interaction. Natural composites enriched in arabinans or galactans and cellulose were recovered. The binding of pectins to cellulose microfibrils may be of considerable significance in the modeling of primary cell walls of plants as well as in the process of cell wall assembly.

Beta vulgaris↗
PubMed1979

Phenotypic stability of the cell wall of Streptococcus mutans Ingbritt grown under various conditions.

Quantitative analyses of cell walls from Streptococcus mutans Ingbritt grown under carbohydrate limitation in the chemostat showed that growth conditions had no statistically significant effect on the composition of polysaccharide, peptidoglycan, or the proportion of polysaccharide in the cell wall. Lysis of cell wall preparations with a muramidase supported this conclusion and further indicated that there was little difference in their overall structure. In contrast, there was a consistent difference between the rates of lysis by this enzyme of organisms grown in 0.2% glucose and 0.5% glucose. Extremes of pH or dilution rate essentially did not influence the immunogenicity of type c antigen in whole organisms irrespective of whether the carbohydrate source was glucose or sucrose. However, differences were found in the immunogenicity of lipoteichoic acid under similar circumstances. The results indicated there was an inherent phenotypic stability in the cell walls of S. mutans Ingbritt despite changes in pH, generation time, and carbohydrate source, and that any changes that did occur were probably due to associated cell-surface components.

Alanine↗
PubMed2005

Probing the cell wall heterogeneity of micro-dissected wheat caryopsis using both active and inactive forms of a GH11 xylanase.

The external envelope of wheat grain (Triticum aestivum L. cv. Isengrain) is a natural composite whose tissular and cellular heterogeneity constitute a significant barrier for enzymatic cell wall disassembly. To better understand the way in which the cell wall network and tissular organization hamper enzyme penetration, we have devised a strategy based on in situ visualization of an active and an inactive form of a xylanase in whole-wheat bran and in three micro-dissected layers (the outer bran, the inner bran and the aleurone layer). The main aims of this study were to (1) evaluate the role of cuticular layers as obstacles to enzyme diffusion, (2) assess the impact of the cell wall network on xylanase penetration, (3) highlight wall heterogeneity. To conduct this study, we created by in vitro mutagenesis a hydrolytically inactive xylanase that displayed full substrate binding ability, as demonstrated by the calculation of dissociation constants (K(d)) using fluorescence titration. To examine enzyme penetration and action, immunocytochemical localization of the xylanases and of feebly substituted arabinoxylans (AXs) was performed following incubation of the bran layers, or whole bran with active and inactive isoforms of the enzyme for different time periods. The data obtained showed that the micro-dissected layers provided an increased accessible surface for the xylanase and that the enzyme-targeted cell walls were penetrated more quickly than those in intact bran. Examination of immunolabelling of xylanase indicated that the cuticle layers constitute a barrier for enzyme penetration in bran. Moreover, our data indicated that the cell wall network by itself physically restricts enzyme penetration. Inactive xylanase penetration was much lower than that of the active form, whose penetration was facilitated by the concomitant depletion of AXs in enzyme-sensitive cell walls.

Amino Acid Sequence↗
PubMed1993

Autologous vein supported with a biodegradable prosthesis for arterial grafting.

To evaluate the potential of a supporting, compliant, biodegradable prosthesis to function as a temporary protective scaffold for autologous vein grafts in the arterial circulation, we implanted vein grafts into the carotid arteries of rabbits, either with (composite grafts) or without (control grafts) such a supporting prosthesis, and evaluated them up to 6 weeks. The control vein grafts showed edema and severe medial disruption with infiltration of polymorphonuclear cells on day 1. Over the study, irregular fibrocyte formation resulted in the formation of a fibrotic vein wall. In contrast, the composite vein grafts showed preservation of smooth muscle cell layers and elastic laminae with a minor inflammatory response. Regular proliferation of fibroblasts, which in some areas were circularly oriented, was observed. We conclude that a supporting, compliant, biodegradable prosthesis can function as a protective scaffold for vein grafts in the arterial circulation, thus reducing damage to the vein graft wall and allowing gradual arterialization.

Animals↗