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PubMed1991

Gene localization, size, and physical map of the chromosome of Streptococcus pneumoniae.

A physical map of the Streptococcus (Diplococcus) pneumoniae chromosome, which is circular and 2,270 kbp in circumference, has been constructed. The restriction enzymes ApaI, SmaI, and SacII were used to digest intact chromosomes, and the fragments were resolved by field inversion gel electrophoresis (FIGE). The digests produced 22, 20, and 29 fragments, respectively. The order of the fragments was deduced from Southern blot hybridization of isolated labeled fragments to separated fragments of the various restriction digests. Genetic markers were correlated with the physical map by transformation of recipient cells with FIGE-isolated DNA fragments derived from genetically marked S. pneumoniae strains. In addition, markers were mapped by the hybridization of cloned genes to FIGE-separated restriction fragments. Six rRNA gene (rrn) clusters were mapped by hybridization to rrn-containing fragments of Haemophilus influenzae.

Base Sequence↗
PubMed2003

Role of the Enterococcus faecalis GelE protease in determination of cellular chain length, supernatant pheromone levels, and degradation of fibrin and misfolded surface proteins.

Gelatinase (GelE), a secreted Zn-metalloprotease of Enterococcus faecalis, has been implicated as a virulence factor by both epidemiological data and animal model studies. Expression of gelE is induced at a high cell density by the fsr quorum-sensing system. In the present study, GelE was shown to be responsible for the instability of a number of Asc10 (aggregation substance) mutant proteins, implying that GelE functions to clear the bacterial cell surface of misfolded proteins. Disruption of GelE production led to increased cell chain length of E. faecalis, from a typical diplococcus morphology to chains of 5 to 10 cells. This function of GelE was also exhibited when the protein was expressed in Streptococcus pyogenes. GelE-expressing E. faecalis strains were more autolytic, suggesting that GelE affects chain length through activation of an autolysin. GelE was also essential for degradation of polymerized fibrin. GelE expression reduced the titer of cCF10, the peptide pheromone that induces conjugation of pCF10, and pCF10 had increased conjugation into non-GelE-expressing strains. These new functions attributed to GelE suggest that it acts to increase the dissemination of E. faecalis in high-density environments.

Bacterial Proteins↗
PubMed1966

Genetic differentiation by nucleic acid homology. IV. Relationships among Lancefield groups and serotypes of streptococci.

Weissman, Sherman M. (National Cancer Institute, Bethesda, Md.), Paul R. Reich, Norman L. Somerson, and Roger M. Cole. Genetic differentiation by nucleic acid homology. IV. Relationships among Lancefield groups and serotypes of streptococci. J. Bacteriol. 92:1372-1377. 1966.-A deoxyribonucleic acid-ribonucleic acid homology technique was used to measure the genetic relatedness among Lancefield groups and serotypes of streptococci. Organisms in different Lancefield groups were related, but were differentiated from each other. Serotypes within group A could be distinguished. Two isolates serologically classified in group A type 1 were indistinguishable. Streptococcus faecalis was only remotely related to streptococci of Lancefield groups A and H, whereas Diplococcus pneumoniae was more closely related to these organisms. The serological data were in good agreement with the results obtained with the homology method.

DNA, Bacterial↗
PubMed1966

Differential effects of deoxyribonucleotides on respiration of virulent pneumococci.

Firshein, William (Wesleyan University, Middletown, Conn.), Robert J. Erickson, and Bernadette A. Gargan. Differential effects of deoxyribonucleotides on respiration of virulent pneumococci. J. Bacteriol. 92:1645-1654. 1966.-Four naturally occurring deoxyribonucleotides affect respiration in three virulent pneumococcal types (Diplococcus pneumoniae) differentially. Deoxyadenylic acid (dAMP) stimulates respiration in type I and slightly stimulates respiration in type III, but has no effect in type II. Deoxyguanylic acid (dGMP) stimulates respiration in type I, inhibits respiration in type II, and has no effect in type III. Thymidylic acid (dTMP) inhibits respiration of type I, but is stimulatory in types II and III. Deoxycytidylic acid (dCMP) inhibits respiration of all three pneumococcal types. Of a large number of related compounds, including many of the naturally occurring deoxynucleosides, nucleosides, nucleotides, purines, and pyrimidines, thymidine is slightly effective in types II and III, and deoxycytidine is slightly inhibitory in all three types. None of the remaining compounds affects respiration significantly. With a few exceptions, there is a correlation between the extent of uptake of each deoxynucleotide in the three types and their ability to stimulate (or inhibit) respiration. The greater the uptake, the greater the enhancement of respiration. The less uptake, the greater the inhibition of respiration. In cell-free extracts of type I, dAMP also stimulates the oxidative decarboxylation of pyruvic acid. During this reaction, dAMP is phosphorylated to deoxyadenosine diphosphate (dADP) and to deoxyadenosine triphosphate (dATP).

Carbon Isotopes↗
PubMed1968

Leukocyte lactate dehydrogenase changes as an indicator of infection prior to overt symptoms.

Lactic acid dehydrogenase (LDH) concentration of rabbit serum and leukocytes was followed during the course of an acute infection with Diplococcus pneumoniae. Control values were obtained prior to infection, and again 4, 24, and 48 hr later. LDH isozymes were characterized by acrylamide gel electrophoresis and quantitated by densitometry. An increase in serum LDH was observed as early as 4 hr after infection. These levels returned to normal in 24 hr and rose again 48 hr after infection. The LDH level of leukocytes, from 10 of 12 infected rabbits, rose rapidly during the 24-hr period after exposure. The levels were two to three times the original preinoculation level for that animal. In six of these rabbits, this LDH elevation occurred 4 hr after inoculation and preceded the onset of fever. Change in the type of leukocyte did not account for the increase in cellular LDH. All infected rabbits showed approximately the same increase in polymorphonuclear leukocytes, but not all developed comparable increases in LDH. The isozyme patterns obtained, when defined amounts of enzyme were applied to the gel for electrophoresis, were characterized for the most part by a three-enzyme pattern. Increasing amounts of enzyme occasionally revealed a fourth, more cathodal, enzyme. The more cathodic enzymes appear to be the most responsive when sudden shifts in enzyme concentration occur within the cell.

Animals↗
PubMed1968

Fractionated strands of bacterial deoxyribonucleic acid. 3. Transformation efficiencies and rates of phenotypic expression.

Preferential binding of guanine-rich ribopolymers to one of the complementary strands of denatured deoxyribonucleic acid (DNA) of Diplococcus pneumoniae permitted the fractionation of the complements in CsCl density gradients. Phenotypic expression of the newly acquired genes for four drug resistances was more rapid in cells transformed by the heavy fractions than in those transformed either by light fractions or by unfractionated DNA. The efficiencies of transformation with the two complements were nearly equal for the four markers tested. Both efficiency and expression results were the same whether we assayed the residual activity or the activity obtained by annealing the fractions with excess recipient DNA.

DNA, Bacterial↗
PubMed1984

Characterization of Neisseria cinerea, a nonpathogenic species isolated on Martin-Lewis medium selective for pathogenic Neisseria spp.

An asaccharolytic, gram-negative, oxidase-positive diplococcus was isolated on Martin-Lewis medium from the cervix of a patient attending an arthritis clinic at Seattle Public Health Hospital, Seattle, Wash. This strain, NRL 32165, did not produce detectable acid from glucose, maltose, sucrose, fructose, mannitol, or lactose in either cystine Trypticase agar (BBL Microbiology Systems, Cockeysville, Md.) or modified oxidation-fermentation medium and was identified presumptively as a glucose-negative Neisseria gonorrhoeae strain, but was identified later as Neisseria cinerea on the basis of its biochemical reactions. Nitrate was not reduced, nitrite (0.001%, wt/vol) was reduced, and polysaccharide was not produced from sucrose. Proline, arginine, and cystine-cysteine were required for growth on defined medium. Strain NRL 32165 did not react with antigonococcal protein I monoclonal antibodies and did not produce immunoglobulin A protease. In DNA:DNA homology studies with N. gonorrhoeae NRL 8038 (F62) and N. cinerea type strain NRL 30003, strain NRL 32165 showed 95% homology relative to N. cinerea and 44% homology relative to N. gonorrhoeae. Thus, the identity of strain NRL 32165 was confirmed as N. cinerea (von Lingelsheim 1906) Murray 1939. Of all Neisseria spp., N. cinerea is most likely to be misidentified as a glucose-negative N. gonorrhoeae strain.

Agglutination Tests↗
PubMed2000

Carried meningococci in the Czech Republic: a diverse recombining population.

Population and evolutionary analyses of pathogenic bacteria are frequently hindered by sampling strategies that concentrate on isolates from patients with invasive disease. This is especially so for the gram-negative diplococcus Neisseria meningitidis, a cause of septicemia and meningitis worldwide. Meningococcal isolate collections almost exclusively comprise organisms originating from patients with invasive meningococcal disease, although this bacterium is a commensal inhabitant of the human nasopharynx and very rarely causes pathological effects. In the present study, molecular biology-based techniques were used to establish the genetic relationships of 156 meningococci isolated from healthy young adults in the Czech Republic during 1993. None of the individuals sampled had known links to patients with invasive disease. Multilocus sequence typing (MLST) showed that the bacterial population was highly diverse, comprising 71 different sequence types (STs) which were assigned to 34 distinct complexes or lineages. Three previously identified hyperinvasive lineages were present: 26 isolates (17%) belonged to the ST-41 complex (lineage 3); 4 (2.6%) belonged to the ST-11 (electrophoretic type [ET-37]) complex, and 1 (0.6%) belonged to the ST-32 (ET-5) complex. The data were consistent with the view that most nucleotide sequence diversity resulted from the reassortment of alleles by horizontal genetic exchange.

Adolescent↗
PubMed2001

Phenotypic and genotypic approaches to characterization of isolates of Neisseria meningitidis from patients and their close family contacts.

Characterization of isolates of Neisseria meningitidis obtained from patients with meningococcal disease or from pharyngeal swabs of asymptomatic carriers can be achieved by several approaches which provide different levels of discrimination. A total of 45 gram negative, oxidase-positive diplococcus strains isolated from 15 individuals with meningococcal disease and 30 of their family contacts were examined by three approaches: serological typing, multilocus enzyme electrophoresis (MLEE), and multilocus sequence typing (MLST). For 10 of the 15 patient and contact groups, all of the isolates were confirmed as meningococci, and the bacteria obtained from the patients and contacts, including their mother or principal caregiver in the case of children, were indistinguishable by all three methods. In the remaining five groups the isolates from the patients were distinct from those recovered from the contacts, and in three examples, in two separate groups, the contacts were shown by MLST to be carrying strains of Neisseria lactamica. The data obtained from the three techniques were consistent, although complete serological typing was possible for only a minority of isolates. Both MLEE and MLST established the genetic relationships of the isolates and identified members of known hypervirulent lineages, but MLST was faster than MLEE and had the additional advantages that it could be performed on noninfective material distributed by mail and that the results from different laboratories could be compared via the internet (http://mlst.zoo.ox.ac.uk).

Adolescent↗
PubMed1977

Glycosidase susceptibility: a probe for the distribution of glycoprotein oligosaccharides in Sindbis virus.

Intact Sindbis virus and Triton-solubilized viral glycoprotein were treated with alpha-mannosidase and with a preparation of mixed glycosidases from Diplococcus pneumoniae to probe the accesibility of carbohydrate units on the viral surface. The products of glycosidase attack on Triton-solubilized virus showed that mose carbohydrate units of the glycoproteins are good substrates for these enzymes. The relative resistance of most of the viral oligosaccharides in intact virus particles showed that much of the carbohydrate is not accessible to glycosidases, probably because it is not exposed at the viral surface. The only completely accessible carbohydrate units on Sindbis glycoproteins were the type A oligosaccharides of E2. This differential accessibility of Sindbis oligosaccharides is discussed in relation to the organization of the viral surface.

Fucose↗
PubMed1977

Properties of "diplophage": a lipid-containing bacteriophage.

We describe the purification and properties of Dp-1, a bacteriophage isolated from Diplococcus pneumoniae. The phage was sensitive to the organic solvents deoxycholate and Sarkosyl, and its infectivity was reduced by treatment with phospholipase C. Electron microscopy indicated the presence of a double-layered coat around the phage particles. Purified phage preparations contained lipid amounting to about 8.5% of the dry weight of the phage, and thin-layer chromatography resolved the lipids into four components. The phage had a buoyant density in CsCl of 1.47 g/cm3, and a sedimentation constant in 0.1 M NaCl of 313S. Analysis in acrylamide gel electrophoresis indicated the presence of three major proteins. Dp-1 DNA shows a density of 1.681 g/cm3. Neutralizing antisera against the phage have a low potency (K less than 120/min).

Adsorption↗
PubMed1978

Removal of carbohydrate from influenza A virus and its hemagglutinin and the effect on biological activities.

Treatment of influenza virus and its purified hemagglutining with glycosidases from Diplococcus pneumoniae, which included beta-galactosidase, beta-N-acetylglucosminidase, and endoglycosidase D, released amino and neutral sugars from the virus and these as well as large oligosaccharides from the purified hemagglutinin. The released glucosamine-containing oligosaccharides were of one discrete size. Large oligosaccharides not removed by the glycosidases were found on the virus as well as the hemagglutinin. Some oligosaccharides on the virus were inaccessible to the enzymes, since they could be removed only from the purified hemagglutinin. Approximately 50% of the hemagglutinin carbohydrates could be removed without effect on hemagglutinating activity. Similarly, removal of 20 to 25% of the carbohydrates from intact virus particles did not alter infectivity.

Carbohydrates↗
PubMed1975

Immunophyletic relationships between actinomycetales and eubacteriales determined by examinations of their cytoplasmic antigens.

Cytoplasms obtained from a total of 205 different strains of Actinomycetales, Eubacteriales, Lower Fungi, and Protozoa were examined against selected anti-cytoplasm antisera using the immunodiffusion and counterimmunoelectrophoresis procedures. Immunological relationships between the different genera have been revealed and, in respect to Eubacteriales, the possible immunophyletic determinants have been discerned. Cytoplasms of Enterobacter, Clostridium, Staphylococcus, and Diplococcus were found to retain the significant linkage determinants between large groups of Eubacteriales and Actinomycetales. Evolutionary implications of the findings are discussed.

Actinomycetales↗
PubMed1975

Fine structure and distribution of extracellular polymer surrounding selected aerobic bacteria.

The structure and distribution of extracellular polymer surrounding Bacillus circulans, Diplococcus (Streptococcus) pneumoniae, Streptococcus salivarius, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Herella vaginacola (Acinetobacter calcoaceticus), and Agrobacterium tumefaciens were studied by electron microscopy. A modified ruthenium red staining procedure was used to examine the fine structure of capsule and slime. Freeze-etching and critical-point drying were used to examine the quantity of unaltered exocellular material. Comparative data demonstrate that fibrillar extracellular polymer surrounding B. circulans, D. pneumoniae, and K. pneumoniae is capsule (cell wall attached) which is characteristic of the producing organism. Capsular polymer generally appeared fibrillar, although globular polymer consisted of capsular subunits bound to S. salivarius and H. vaginacola. Exocellular slime was present about S. aureus, P. aeruginosa, and A. tumefaciens.

Acinetobacter↗
PubMed1975

Alterations in hepatic chromatin template availability during infection.

Hepatic chromatin was isolated from rats at various times after inoculation with either live or heat-killed bacteria. The chromatin was assayed under conditions that allow determination of the DNA template available to support in vitro transcription. Both a fulminant Diplococcus pneumoniae and a milder Salmonella typhimurium infection produced time-related increases in hepatic chromatin template availability when compared to chromatin isolated from rats inoculated with heat-killed bacteria. Both timing and magnitude of increased template availability correlated with the severity of the infection. The earliest change observed was a 50 percent rise in availability noted 4 h after inoculation with D. pneumoniae. This preceded the onset of fever, as well as other known heaptic consequences of systemic infection. After 24 h of infection the maximum rise of 90 percent occurred. Similar changes developed during S. typhimurium infection, but were slower in onset and smaller in magnitude. Adrenalectomy prior to infection enhanced the severity of the disease but markedly blunted the increase in template availability. The data are consistent with the hypothesis that systemic infection regulates the hepatic metabolic response to infection through transcriptional control and that a permissive or stimulatory action of glucocorticoids is involved in the increases in template availability effected.

Adrenalectomy↗
PubMed1976

Altered hepatic glycogen metabolism and glucoregulatory hormones during sepsis.

Levels of glucose, insulin, and glucagon in portal vein plasma and of liver glycogen and cyclic AMP and activities of glycogen synthase and phosphorylase in liver were assayed in control (CONT) rats and rats infected (INF) with Diplococcus pneumoniae. In INF rats compared with CONT rats, insulin and glucagon levels were higher (8,12,24 h). Activity of synthase I was lower (8, 12, 24 h) and of phosphorylase higher (12 and 24 h) in INF rats. Cyclic AMP levels were higher in INF rats at 12 and 24 h. Total synthase activity was lower in INF rats at 24 h. Glucose given intravenously increased glycogen less in INF than in CONT rats and activated synthase and inactivated phosphorylase in all animals except at 24 h in INF rats. However, in situ perfusion of the livers at 24 h with glucose in buffer decreased phosphorylase activities in all animals and increased synthase I activities in CONT but not INF rats.

Animals↗
PubMed1977

Antimicrobial activity of tibezonium (TBZ).

The activity in vitro of tibezonium (Rec 15-0691), a new 1,5-benzodiazepine derivative, has been investigated. The drug was found active especially against Streptococcus, Diplococcus and Corynebacterium strains which are agents of oropharyngeal diseases. The activity of tibezonium was pH dependent against Staphylococcus aureus SG 511 and Streptococcus pyogenes 821 (at pH 8.0-8.5 It was more active) and the presence of horse serum provoked a small decrease of the antimicrobial properties. No interference on the activity of the tibezonium has been found in presence of smokers and non-smokers saliva.

Anti-Bacterial Agents↗
PubMed1967

Bacterial interference induced in embryonated eggs by staphylococci.

Studies of experimental infections in embryonated eggs demonstrated that prior allantoic infection with avirulent staphylococci afforded significant protection against subsequent challenge with virulent strains. All strains of coagulase-positive and coagulase-negative staphylococci tested that were relatively avirulent for embryonated eggs were capable of producing interference. The interference induced afforded protection not only against challenge with virulent staphylococci, but also against Diplococcus pneumoniae, Salmonella typhimurium, Escherichia coli, Proteus mirabilis, and one strain of influenza virus (A(2)J 305). Prior allantoic infection with avirulent staphylococci also protected against intravenous as well as allantoic infection with challenge strains.Interference required infection with viable bacteria. The onset of interference appeared within a few minutes after injection of the interfering strain, but was not maximal until 24 hours had elapsed between injection of the interfering and challenge strains. The protection afforded by the production of interference could not be overcome by increased inoculum size of the challenge strain and extended even to challenge with 10(9) bacteria. Studies of in vitro and in vivo growth of challenge strains in allantoic fluid demonstrated that some interfering strains inhibited growth of the challenge strains. Other strains produced interference without producing prolonged inhibition of the growth of challenge strains. Similarly, interference could not be attributed to attenuated virulence of the challenge organisms. All interfering strains studied produced enhanced bactericidal activity of whole blood from the affected embryos, but whether this affected leukocyte activity, opsonization, or other host defense mechanisms has yet to be determined.

Animals↗