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| Rapid Commun Mass Spectrom, 1999, 13(23), 2320 - 6 Direct mass spectrometric analysis of Bacillus spores; Beverly MB et al.; Spores from the Bacillus species, B . cereus, B . anthracis, B . thuringensis, B . lichenformis, B . globigi, and B . subtilis, were examined by direct probe mass spectrometry using electron ionization (EI) and positive and negative chemical ionization (CI) . Molecular ions from free fatty acids and nucleic acids were observed in the 70eV spectra as were fragments from glycerides . Spectra obtained with isobutane positive chemical ionization (CI(+)) were dominated by ions associated with pyranose compounds such as N-acetylglucosamine (NAG) . Unlike the positive ion spectra, the negative ion spectra of the spores were very simple and contained few peaks . The M(-.) ion from dipicolinic acid (DPA) was the base peak in the negative ion spectra of all spore species except those from B . lichenformis . The negative ion of DPA produced such a strong signal that 10(8) colony forming units (CFUs) of B . cereus spores could be detected directly in 0.5 g of ground rice . Principal component analysis (PCA) of the spectra revealed that only CI(+) spectra contained differences that could be used to identify the spectra by species . Differentiation of the CI(+) spectra by PCA was attributed to variances in the peaks associated with the bacterial polymer poly(3-hydroxybutyrate) (PHB) and NAG . Similar differences in PHB and NAG peaks were detected in the CI(+) spectra of a suite of vegetative Bacillus stains grown with various media . Mol Microbiol, 1999 Jun, 32(5), 1043 - 53 PlcR is a pleiotropic regulator of extracellular virulence factor gene expression in Bacillus thuringiensis; Agaisse H et al.; Members of the Bacillus cereus group (B . anthracis, B . cereus, B . mycoides and B . thuringiensis) are well-known pathogens of mammals (B . anthracis and B . cereus) and insects (B . thuringiensis) . The specific diseases they cause depend on their capacity to produce specific virulence factors, such as the lethal toxin of B . anthracis and the Cry toxins of B . thuringiensis . However, these Bacillus spp . also produce a variety of proteins, such as phospholipases C, which are known to act as virulence factors in various pathogenic bacteria . Few genes encoding these virulence factors have been characterized in pathogenic Bacillus spp . and little is known about the regulation of their expression . We had previously reported that in B . thuringiensis expression of the phosphatidylinositol-specific phospholipase C gene is regulated by the transcriptional activator PlcR . Here we report the identification of several extracellular virulence factor genes by the virtue of their PlcR-regulated expression . These PlcR-regulated genes encode degradative enzymes, cell-surface proteins and enterotoxins . The PlcR-regulated genes are widely dispersed on the chromosome and therefore do not constitute a pathogenic island . Analysis of the promoter region of the PlcR-regulated genes revealed the presence of a highly conserved palindromic region (TATGNAN4TNCATA), which is presumably the specific recognition target for PlcR activation . We found that the plcR gene is also present in and probably restricted to all the members of the B . cereus group . However, although the polypeptide encoded by the B . cereus PlcR gene is functionally equivalent to the B . thuringiensis regulator, the polypeptide encoded by the B . anthracis gene is truncated and not active as a transcriptional activator . PlcR is the first example described of a pleiotropic regulator involved in the control of extracellular virulence factor expression in pathogenic Bacillus spp . These results have implications for the taxonomic relationships among members of the B . cereus group, the virulence properties of these bacteria and the safety of B . thuringiensis-based biopesticides. Infect Immun, 1998 May, 66(5), 2163 - 9 Integrated physical and genetic mapping of Bacillus cereus and other gram-positive bacteria based on IS231A transposition vectors; Leonard C et al.; The genome structure of Bacillus cereus is relatively complex, its DNA being modulated between a size-varying chromosome and large plasmids . To study the genetic organization of the B . cereus type strain ATCC 14579, thermosensitive transposition vectors were designed on the basis of IS231A-derived cassettes containing uncommon restriction sites . A highly preferred insertion site for IS231A was detected in the chromosome by Southern blotting and pulsed-field gel electrophoresis (PFGE) analyses of independent insertion mutants . However, once this insertional hot spot was occupied, secondary IS231A insertions occurred randomly, as demonstrated by isolation of independent B . cereus auxotrophs at a frequency of approximately 0.6% . The hot-spot site, as well as several auxotrophic mutations, were mapped by using NotI, SfiI, and AscI PFGE restriction profiles . It was confirmed by sequencing that one of the insertions, generating an Ade- phenotype, had disrupted a gene of the purine synthesis pathway . These results showed that combined PFGE and sequencing analyses of mini-IS231A insertions enable the construction of integrated physical and genetic maps of B . cereus type strain . Moreover, the presence of the ultrarare I-SceI restriction site in the mini-IS231A allowed the isolation, in double-insertion mutants, of contiguous and nonoverlapping large chromosomal fragments, convenient for direct sequencing . The system detailed in this report is therefore a powerful tool for comparative genetic studies among members of the B . cereus group (i.e., B . cereus, B . thuringiensis, B . mycoides, and B . anthracis) and could also be applied to more distantly related gram-positive bacteria. Heart Lung, 1997 May-Jun, 26(3), 249 - 51 Bacillus species pseudomeningitis; Cunha BA et al.; Bacillus species are aerobic gram-positive bacilli that are usually found in nature in the soil and dust . Except for B . anthracis, Bacillus species are organisms of low virulence, and only rarely cause infections in immunocompromised hosts . The recovery of Bacillus species from body fluids in healthy patients would suggest a Bacillus species pseudoinfection . Bacillus species has been associated with both pseudobacteremia and least commonly, pseudomeningitis . The Bacillus organisms usually contaminate liquid culture media, which have been implicated in Bacillus pseudoinfections of the blood and cerebrospinal fluid . We report a case of Bacillus pseudomeningitis in a normal host . To our knowledge, this is the third case of Bacillus pseudomeningitis reported in the literature. Epidemiol Mikrobiol Imunol, 1994 Dec, 43(4), 188 - 91 {150 years since the birth of R . Koch--his life and work}; Pospisil R; In December 1993 150 years have elapsed since the birth of Robert Koch . Koch began his research activities already as a rural physician . Later, from 1880 he worked in the Imperial Health Institute in Berlin, from 1885 he was as professor in charge of the Institute of Hygiene of the Medical Faculty of Berlin University . Greater opportunities for research were offered to him in the Institute for Infectious Diseases in Berlin . R . Koch laid the foundations of scientific microbiology, his activities were, however, also closely linked with epidemiology . His discoveries include evidence of B . anthracis, V . cholerae and in particular M . tuberculosis (1882) . He studied also the etiology of wound infections . He enriched microbiology by new cultivation, staining and microscopic techniques, by using vapour during sterilization as well as investigations of the effect of new disinfectants . A major part of his research was devoted to tropical diseases which he studied during six expeditions . Koch was not only concerned with laboratory research, he implemented also many epidemiological field projects . Many scientists who later became famous worked with him . In 1905 Koch was awarded the Nobel Prize . R . Koch died on May 27, 1910. Microbiology, 1994 May, 140 ( Pt 5), 1015 - 22 Characterization of Bacillus thuringiensis and related bacteria by ribosomal RNA gene restriction fragment length polymorphisms; Priest FG et al.; Ribosomal RNA gene restriction patterns have been determined for 43 strains of Bacillus thuringiensis representing 10 serovars and eight reference strains of B . anthracis, B . cereus and B . mycoides . Strains within a B . thuringiensis serovar produced highly related or identical ribotype patterns: in particular, 12 strains of serovar israelensis, five strains of serovar kurstaki, two strains of serovar galleriae and three strains of serovar aizawa produced ribotype patterns consistent with serotype designations . Moreover, variety tenebrionis (serotype 8a8b), a coleopteran pathogen, could be distinguished from the more common lepidopteran pathogens of this serotype (serovar morrisoni) by ribotyping . The correlation of ribotype patterns with serotype suggests a clonal population structure for B . thuringiensis. Int J Pediatr Otorhinolaryngol, 1992 May, 23(3), 229 - 36 Modulation of humoral and cellular resistance in children with laryngeal papillomatosis; Jakubikova J et al.; As accessory cells in immunity response immunoglobulin and lymphocytes participate in antitumor immunity . Quantitative changes in concentrations and numbers were studied once before therapy, without examining the functional state . In order to gain more information on the humoral response during and after treatment, and in cases of recurrence, bactericidal antibodies against B . anthracis were determined by means of 51Cr-labeled microbes . The results of the present study show that IgG levels were normal and IgA and IgM normal or increased . In only 2 children (0.8%) the levels of serum IgM were lowered . Although a high percentage of increased trend values of bactericidity in cured children was found (75%), the percentage in children with recurrences reaching 50%, the differences are considered statistically insignificant . Following T lymphocyte, figures a significant decrease in juvenile laryngeal papillomatosis (JLP) patients were found. Przegl Epidemiol, 1991, 45(3), 197 - 205 {Decontamination of soil after bacterial warfare experiments on Gruinard Island}; Mierzejewski J et al.; Bombs containing B . anthracis spores were detonated on Gruinard island in 1942 and 1943 as a part of a British research programme set up in response to fears that the Germans were developing biological weapons . In 1986 island was decontaminated by spraying with 5% formaldehyde . As a demonstration of confidence in the success of the decontamination operation a flock of 40 sheep was allowed to graze for several months with no ill effects. Wei Sheng Wu Xue Bao, 1990 Feb, 30(1), 7 - 15 {Study on the discrimination of bacteria by gas chromatographic profiles of cellular monosaccharides}; Zhou F et al.; A procedure for obtaining gas chromatographic (GC) profiles of bacterial cellular monosaccharides was described . Some of the unknown component peaks in these profiles were identified . And, based on the complete linkage cluster analysis with the Euclidean distance coefficient, the interpretation of the resulting cellular monosaccharides of bacteria were performed by mini-computer . By means of this method, the discrimination of 5 species (24 strains) of aerobic endospore-forming bacteria . The results showed that there were defined differences between the profiles of cellular monosaccharides of B . anthracis and B . cereus . This procedure has provided a useful method for the classification and identification of microorganisms, for their physiological and biochemical studies, and for studies on their subcellular components. Tokai J Exp Clin Med, 1988, 13 Suppl, 239 - 52 Bordetella pertussis adenylate cyclase: the gene and the protein; Glaser P et al.; Using the adenylate cyclase-calmodulin interaction as a tool, the B . pertussis cya gene was cloned in a cya defective E . coli strain harbouring a plasmid which expressed high levels of calmodulin . The determination of the nucleotide sequence of the gene showed that adenylate cyclase is synthesized as a large precursor of 1706 amino acids . The calmodulin-stimulated catalytic activity resides in the amino-terminal 400 amino acids whereas the 1300 amino acid carboxy-terminal part of the precursor is endowed with haemolytic activity . The catalytically active 43 kDa form of adenylate cyclase is organized in two domains: the N-terminal domain of 25 kDa harbors the catalytic site, and the 18 kDa C-terminal domain carries the main calmodulin-binding site . Immunological relatedness established between B . pertussis, B . anthracis and rat brain adenylate cyclases suggests a common evolutionary origin of a central domain of these calmodulin-stimulated enzymes . The secretion of the adenylate cyclase-haemolysin bifunctional protein (cyclolysin) requires the expression of three additional genes, contiguous to the cya gene . These four genes appear to form a single operon . The mechanism of secretion of the bifunctional protein should be similar to that described for E . coli alpha-haemolysin. J Bacteriol, 1987 Nov, 169(11), 5271 - 8 Bacillus subtilis (natto) plasmid pLS20 mediates interspecies plasmid transfer; Koehler TM et al.; The 55-kilobase plasmid, pLS20, of Bacillus subtilis (natto) 3335 promotes transfer of the tetracycline resistance plasmid pBC16 from B . subtilis (natto) to the Bacillus species B . anthracis, B . cereus, B . licheniformis, B . megaterium, B . pumilus, B . subtilis, and B . thuringiensis . Frequency of pBC16 transfer ranged from 2.3 x 10(-6) to 2.8 x 10(-3) . Evidence for a plasmid-encoded conjugationlike mechanism of genetic exchange includes (i) pLS20+ strains, but not pLS20- strains, functioned as donors of pBC16; (ii) plasmid transfer was insensitive to the presence of DNase; and (iii) cell-free filtrates of donor cultures did not convert recipient cells to Tcr . Cotransfer of pLS20 and pBC16 in intraspecies matings and in matings with a restriction-deficient B . subtilis strain indicated that pLS20 was self-transmissible . In addition to mobilizing pBC16, pLS20 mediated transfer of the B . subtilis (natto) plasmid pLS19 and the Staphylococcus aureus plasmid pUB110 . The fertility plasmid did not carry a selectable marker . To facilitate direct selection for pLS20 transfer, plasmid derivatives which carried the erythromycin resistance transposon Tn917 were generated . Development of this method of genetic exchange will facilitate the introduction of plasmid DNA into nontransformable species by use of transformable fertile B . subtilis or B . subtilis (natto) strains as intermediates. Boll Soc Ital Biol Sper, 1985 Feb 28, 61(2), 199 - 204 Biological activity of 4-hydroxyisophthalic acid derivatives . III . Variously substituted anilides with antimicrobial activity; Piscopo E et al.; A series of 1,3-bis-anilides of 4-hydroxyisophthalic acid was prepared and investigated for antibacterial and antifungal activities . The prepared compounds (I-XIV), of the general formula (A), where Xn = 2-NO2 (I); 2,4-(NO2)2 (II); 2,4-NO2, Cl (III); 2,4-NO2,CF3 (IV); 3,4-NO2,Cl (V); 2,4-Cl,NO2 (VI); 2,5-Cl,NO2 (VII); 2,4,6-Cl,NO2,Cl (VIII); 2,4-Br, NO2 (IX); 2-CF3 (X); 3-CF3 (XI); 2,5-Cl,CF3 (XII); 2,5-CH3,Cl (XIII); 3,4-Cl,CH3 (XIV), were obtained in satisfactory yield by reacting 4-hydroxyisophthalic acid with the appropriate substituted aniline . (Formula: see text) . The prepared compounds were tested for antimicrobial activity by a disk-diffusion assay (Kirby-Bauer modified) . The organisms used were the following: S . aureus, B . subtilis, B . anthracis, M . paratuberculosis 607, E . coli Bb, S . typhi, S . typhimurium, S . paratyphi B, Pr . vulgaris, K1 . pneumoniae, Ps . aeruginosa, C . albicans, and A . niger . The results of the antimicrobial screening showed that a number of substituted anilides exhibited varying degrees of activity against Gram-positive and Gram-negative bacteria, and fungi, nitro-halogen-derivatives being the most interesting members of the series. Boll Soc Ital Biol Sper, 1984 Dec 30, 60(12), 2273 - 9 Biological activity of 4-hydroxyisophthalic acid derivatives . II . Anilides with antimicrobial activity; Piscopo E et al.; A series of 1,3 -bis-anilides of 4-hydroxyisophthalic acid was prepared and tested for antibacterial and antifungal activity . The prepared compounds (I-XVIII), of general structure (A), (Formula: see text) where Xn = H (I); 2-F (II); 3-F (III); 4-F (IV); 2-Cl (V); 3-Cl (VI); 4-Cl (VII); 2-Br (VIII); 3-Br (IX); 4-Br (X); 2-J (XI); 3-J (XII); 4-J (XIII); 2,5-Cl2 (XIV); 2,4-Br2 (XV); 2,3,4-Cl3 (XVI), 2,4,5-Cl3 (XVII); 2,4,6-Cl3 (XVIII), were investigated for the purpose of determining the effect of halogen-substitution on the aniline rings of (A) . All of these compounds were prepared in satisfactory hield by reaction of 4-hydroxyisophthalic acid with the appropriate aromatic amine at 175 degrees for 3 hours . The 1,3-bis-anilides prepared in this investigation were screened for antimicrobial activity by a disk-diffusion assay (Kirby-Bauer modified) . The organisms used were laboratory cultures of S . aureus, B . subtilis, B . anthracis, M . paratuberculosis 607, E . coli Bb, S . typhi, S . typhimurium, S . paratyphi B, Pr . vulgaris, Kl . pneumoniae, Ps . aeruginosa, C . albicans, and A . niger . The results of this investigation indicated that most of the 1,3-bis-(halogen-anilides) of 4-hydroxyisophthalic acid had little or no antifungal activity "in vitro", while showed significant activity against Gram+ and Gram- bacteria . Some fluoro-derivatives showed inhibitory activity especially toward S . aureus and M . paratuberculosis . Iodo-derivatives showed broad-spectrum "in vitro" antimicrobial activity, and had some antifungal activity. Boll Soc Ital Biol Sper, 1984 Jun 30, 60(6), 1169 - 75 Biological activity of 4-hydroxyisophthalic acid derivatives . Hydrazones with antimicrobial activity; Piscopo E et al.; The following hydrazono derivatives (I-XIX) of type (A) (sequence in text) where Rn = (sequence in text ) (I-XVII); (sequence in text) (XVIII); -CCl3 (XIX); and Xn = H (I); 2-Cl (II); 3-Cl (III); 4-Cl (IV); 2-NO2 (V); 3-NO2 (VI); 4-NO2 (VII); 2-OH (VIII); 3-OH (IX); 4-OH (X); 4-F (XI); 3,4-OCH3,OH (XII); 3,4,5-OCH3,OH,J (XIII); 3,4-OCH3,OCH3 (XIV); 2,4-Cl2 (XV); 3,4-Cl2 (XVI); 2,6-Cl2 (XVII); were prepared and characterized in an attempt to make available for testing a representative selection of hitherto unreported 4-hydroxyisophthalic acid derivatives . The new compounds in question were obtained in satisfactory yield by condensation of 4-hydroxyisophthalic acid hydrazide with the appropriate aldehydes . The prepared compounds were tested for their possible activity against Gram-positive (S . epidermidis, B . subtilis, B . anthracis) and Gram-negative bacteria (P . aeruginosa, B . melitensis, S . typhi O, S . typhi H, S . infantis, S . paratyphi B, E . coli Bb, E . coli 7075), and fungi (C . albicans, A . niger, S . cerevisiae) . The "in vitro" antimicrobial assays were carried out using the paper disk technique (Kirby-Bauer modified) . The influence of certain structural modifications on the antimicrobial activity was evaluated. Boll Soc Ital Biol Sper, 1984 Mar 30, 60(3), 501 - 7 {Biological activity of 4-hydroxy-5-formylbenzoic acid derivatives . II . Esters and Schiff bases with antimicrobial activity}; Piscopo E et al.; A number of hitherto undescribed 4-hydroxy-5-formylbenzoic acid derivatives (A), have been prepared and characterized . (formula; see text) Esters (X = CH3) and Schiff's bases (Z = N-aryl) were prepared by conventional methods and were obtained in satisfactory yield and in a good state of purity . The prepared compounds have been tested for "in vitro" activity against Gram+ bacteria (S.epidermidis, B.subtilis, B.anthracis, M.paratuberculosis), Gram- bacteria (P.aeruginosa, S.typhi murium, E.coli Bb, S.typhi O, S.typhi infantis, S.paratyphi A, S.paratyphi B) and fungi (C.albicans, A.niger, S.cerevisiae) by agar-diffusion method (Kirby-Bauer modified) . The prepared compounds, generally, showed inhibitory activity against Gram+ bacteria . Esters (A: X = CH3) showed antibacteric and antimycotic activity . The greatest activity was observed in the methyl ester (XV) of 4-hydroxy-5-formylbenzoic acid (I). Boll Soc Ital Biol Sper, 1983 Nov 30, 59(11), 1644 - 8 Biological activity of 4-hydroxy-5-formylbenzoic acid derivatives; Piscopo E et al.; A group of thirty 4-hydroxy-5-formylbenzoic acid derivatives of general formula: (formula; see text) where (formula; see text) have been prepared and characterized in an attempt to make available for testing a representative selection of hitherto undescribed hydroxyformylbenzoic acid derivatives . The products, which are listed in Table I, with pertinent data, have been obtained in satisfactory yield and in a good state of purity . The prepared compounds have been tested for "in vitro" activity against three fungi (A . niger, C . albicans, S . cerevisiae), six Gram- bacteria (E . coli Bb, S . typhi, S . infantis, S . paratyphi A, B . melitensis, P . mirabilis) and four Gram+ bacteria (M . paratuberculosis ATCC 607; S . epidermidis, B . subtilis, B . anthracis), by the agar diffusion method (Kirby-Bauer modified) . In general, the results of the tests indicated that most of the compounds: a) didn't exhibit antifungal activity "in vitro"; b) had little activity on Gram- bacteria; showed inhibitory activity toward Gram+ species, in particular toward M . paratuberculosis . Other activities of pharmaceutical interest will be tested; the screening program includes tests for cardiac activity . The results of these studies will be published as soon as they are complete. Boll Soc Ital Biol Sper, 1982 Dec 30, 58(24), 1637 - 42 {Hydrazide derivatives of fluorobenzoic acids and their antimicrobial activity}; Piscopo E et al.; The compounds of formula (A) were prepared by reaction between Rn-substituted benzoyl hydrazides and R-substituted benzoyl chlorides; the compounds of formula (B) were obtained by condensing R-substituted benzoyl chlorides with isonicotinic hydrazide . All the compounds were tested for in vitro activity against five Gram+ bacteria (S . aureus, S . epidermidis, B . subtilis, B . anthracis, M . paratuberculosis ATCC 607), seven Gram-bacteria (S . paratyphi A, S . paratyphi B, E . coli, B . abortus, B . melitensis, P . aeruginosa, P . mirabilis) and three fungi (C . albicans, A . niger, S . cerevisiae), by agar-diffusion method (Kirby-Bauer modified) . The prepared compounds generally showed inhibitory activity against Gram+ bacteria . The greatest activity was observed in the compounds of general formula (B); they were especially inhibitory toward M . paratuberculosis ATCC 607. J Immunol Methods, 1982 Nov 12, 54(3), 361 - 9 Variations on the staining method in quantitative indirect immunofluorescence assays for Bacillus spores, and the use of fluorescein--protein A; Phillips AP et al.; Quantitative indirect immunofluorescence assays for B . anthracis and B . cereus spores fixed on multispot microscope slides have been performed using a microfluorometer to measure the fluorescence of individual bacteria . A study has been made of variations of the indirect assay sequence, in which the washing operation between application of 1st and 2nd antibody types was omitted . In one modification the addition of the indirect antibody was deferred, and in the second the direct and indirect reagents were added simultaneously to the spores at the start of the incubation period . This simultaneous addition method shows promise for wide application in diagnostic serology . Evidence is presented that fluorescein-protein A (F-PA) can be successfully substituted for fluorescein/sheep anti-rabbit antibody (F-SAR) in the indirect spore assay, and that it is far more active than the F-SAR on a weight basis . About twice as many F-PA molecules as F-SAR molecules are bound to the spore at saturation. Biol Bull Acad Sci USSR, 1978 Sep-Oct, 5(5), 641 - 3 Antibacterial effect of some combinations of pesticides of pure cultures of microorganisms; Merenyuk GV et al.; The investigations conducted showed that the antibacterial effect of dinitro-o-cresol, cuprozane, and trichlorfon is due to their chemical structure and to the species of microorganisms on which they act . Dinitro-o-cresol and Cuprozane possess selective toxicity with respect to B . anthracis and Rh . gracilis and cuprozane with respect to Ch . perfringens . The method of evaluating the effect of combinations of chemical compounds consisting of two or more components which have been developed made it possible to detect the antibacterial effect of mixtures consisting of the indicated pesticides . It was established that the combinations studied possess synergic and additive effects, which also depend on the chemical structure of the pesticides and the species of microorganisms. Can J Microbiol, 1978 Aug, 24(8), 986 - 93 Partial characterization of a cubic Bacillus phage; Ackermann HW et al.; Partial characterization of a cubic Bacillus phage . Can . J . Microbiol . 24: 986--993 . Phage Bam35 is an icosahedron of about 63 nm in diameter . It has a double capsid with spikes at the vertices, and a tail which seems to appear upon nucleic acid ejection . The phage contains DNA and, probably, lipids which seem to be located in the inner coat . The phage is Bacillus-specific, UV- and lipase-resistant, and sensitive to heat, chloroform, and ether . The latent period is 50 min and the burst size is 39 . Page Bam35 belongs to a new virus group which includes a phage of B . anthracis and four phages of gram-negative bacteria harboring drug-resistance plasmids. Appl Environ Microbiol, 1978 Jun, 35(6), 1109 - 15 Transduction in Bacillus thuringiensis; Thorne CB; Bacteriophage CP-51, originally reported as a generalized transducing phage for Bacillus cereus and B . anthracis, has been shown to carry out generalized transduction in several strains of B . thuringiensis . A newly isolated phage, CP-54, which has a broader host range than CP-51, also mediates generalized transduction in B . thuringiensis . CP-51 and CP-54 are similar in size and morphology and are related serologically, but they are not identical . CP-54 is more cold labile than CP-51, and, as with CP-51, its stability both at 0 and 15 degrees C is enhanced by the presence of 0.02 M Mg2+ . Some examples of cotransduction of linked markers in B . thuringiensis are presented, demonstrating the feasibility of chromosomal mapping in this organism . The rare occurrence of cross-transduction among strains of B . thuringiensis is probably a reflection of nonhomology rather than restriction, since phage itself did not appear to be restricted when grown on a particular host and assayed with other hosts as indicator. Zentralbl Bakteriol Naturwiss, 1978, 133(3), 250 - 60 Sensitivity to lytic agents and DNA base composition of several aerobic spore-bearing bacilli; Candeli A et al.; The authors studied the possible relationship between a genetic characteristic, like DNA base composition, and certain phenotypic characteristics, i.e., sensitivity to lytic agents, morphology of colonies, and biochemical reactions in 34 strains of spore-bearing bacilli . From the results obtained two groups of bacilli have been identified . The first group includes the species B . subtilis, B . pumilus, B . licheniformis, and B . firmus and one strain of B . megaterium . The mean value of the GC% of the DNA is 44.22 +/- 1.76 . All the strains examined are highly sensitive to lysozyme and resistant to sodium lauryl sulphate (S.L.S.); the surface colonies have a "rhizoid" appearance and the microcolonies on slide microculture are star-shaped . The second group includes the species B . cereus, B . cereus var . mycoides, B . anthracis, and B . thuringiensis . The mean value of the GC% of the DNA is 33.65 +/- 0.59 . All the strains belonging to this group are resistant to both lysozyme and S.L.S., and the surface macro-colonies and the microcolonies have a "medusae head" appearance . The two groups also have certain different biochemical reactions; e.g., anaerobic growth and the egg yolk reaction, with few exception, are negative for the first group and positive for the second; furthermore, the strains in the first group (with rare exceptions) cause fermentation in the three carbohydrates, glucose, arabinose, and xylose, while glucose only is fermented by all strains with one exception in the second group . The position of B . megaterium is not yet clear, although one strain may certainly be included in the first group . Lysis by lipase is extremely variable and does not correlate with any of the other characteristics studied . The other species studied in relation to the characteristics, considered in our research (B . coagulans, B . macerans, B . polymyxa, B . laterosporus, B . alvei, B . circulans, B . stearothermophilus, and B . brevis), are not susceptible to grouping, either in the first, or in the second or even in a separate group. Ann Sclavo, 1975 May-Jun, 17(3), 271 - 4 {Morphological and physiological studies on schizomycetes . Morphogenesis and cytoarchitecture of microbial colony . IV . B.megaterium}; Palmas F et al.; Unlike B . anthracis and B . cereus, the B . megatherium shows a disordered cytoarchitecture . Since the factors conditioning the growth of the colonies are the same, this is due to a different parting mechanism of daughter cells. Ann Sclavo, 1975 Mar-Apr, 17(2), 154 - 62 {Morpho-physiological research on Schizomycetes . Morphogenesis and cytoarchitecture of the microbial colony . I: B . anthracis}; Scarpa B et al.; The cytoarchitecture of B . anthracis can be easily studied in serial sections both at the light and at the electron microscope . The morphogenesis of the colony makes clear the peculiar structure of B . anthracis which seems essentially due to the chemical and physical characteristics of the cell envelopes and to the incomplete division of daughter cells . Other factors such as surface tension, humidity, mechanical obstacles and regressive phenomena, seem to be active, in B . anthracis, only since the third day.
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