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PubMed1977

Specific agglutination of Escherichia coli O128B12 by the mannose-binding proteins of Pseudomonas aeruginosa.

The mannosephilic haemagglutinins of Pseudomonas aeruginosa were found to agglutinate cells of Escherichia coli O128B12, to be adsorbed onto them and to attach peroxidase to them. These reactions were specifically inhibited by D-mannose. No agglutination by this Pseudomonas haemagglutinin was obtained when several other enteropathogenic types of Escherichia coli and some other Gram-negative bacteria were examined. Concanavalin A, which also reacted with Escherichia coli O128B12 cells, interacted with some of the other bacteria examined, too. Escherichia coli O128B12 was not agglutinated by the Pseudomonas galactosephilic haemagglutinins and those of the plant Phaseolus vulgaris. Its maximal agglutination by the Pseudomonas mannosephilic haemagglutinins was obtained employing cells grown for 4-6 h in conventional media. The growth temperature, aeration and presence of certain amino acids, but not D-mannose, in the culture medium had some effect on the agglutination in tensity; pH 6-8 was optimal for it and only at pH 3.0-3.2 no agglutination was observed. Treatment of the bacteria by proteolytic enzymes, ethanol or formaldehyde did not alter their agglutinability by either the Pseudomonas lectin or by antibodies produced against them in rabbits. Heating of the bacteria to 100 degrees C prevented their agglutination by the Pseudomonas lectin and lowered their ability to adsorb it, but did not significantly affect their reactions with the rabbit antibodies.

Agglutination↗

PubMedDate not supplied

[The esterase activity of a pigmented bacterial group belonging to the Pseudomonas genus].

Bacteria belonging to the Pseudomonas genus and isolated from zonal soils in different geographical zones of the USSR as well as from the rhizosphere of cultivated and wild plants were tested for their esterase activity. The studied collection of cultures included 205 strains of different pigmented Pseudomonas species which, according to the conventional taxonomy, were assigned to the so-called "Pseudomonas fluorescens complex". As was shown in this study, many Pseudomonas species are potential producers of nonspecific esterases. P. maltophilia and P. geniculata synthesizing pyomelanin have the highest activity of esterase. The activity of esterase correlates with the formation of a melanin-like pigment in Pseudomonas cultures. It also correlates with the species to which a culture belongs, which makes it possible to use this property as an additional criterion for the identification of Pseudomonas species.

Esterases↗

PubMed1986

Fimbriae (pili): molecular basis of Pseudomonas aeruginosa adherence.

Pseudomonas aeruginosa produces polar pili which promote the adherence of the organism to host mucosal surfaces and to blood-borne phagocytic cells such as polymorphonuclear leukocytes. Pseudomonas polar pili are flexible filaments of 52 A diameter and 2500 nm average length. They consist of a single type of protein subunit, pilin, of molecular weight 15,000, which is arranged in a helical mode of 5 subunits per turn and a pitch of 41 A. Purified whole pili, and anti-pilus antiserum both inhibited the interaction of Pseudomonas aeruginosa strains with human buccal epithelial cells and PMNs, suggesting that Pseudomonas adherence to these mammalian cells is pilus mediated. No correlation was found between the level of cell surface fibronectin on human buccal endothelial cells and the adherence of Pseudomonas bacteria. Pseudomonas adherence to buccal endothelial cells obtained from patients with cystic fibrosis was somewhat less than that to buccal endothelial cells obtained from healthy individuals. Fibronectin levels on buccal endothelial cells from patients with cystic fibrosis were not significantly different than those found on buccal endothelial cells from healthy individuals. Studies with peptide fragments derived from purified pili showed that only one peptide encompassing 23 amino acid residues at the C-terminus of the pilus protein was able to inhibit in vitro adherence of P. aeruginosa PAK to human buccal cells. This peptide domain was tentatively assigned the receptor-binding function.

Amino Acid Sequence↗

PubMed1986

Cloning of the gene coding for the outer membrane receptor protein for ferric pseudobactin, a siderophore from a plant growth-promoting Pseudomonas strain.

Plant growth-promoting Pseudomonas B10 produces its yellow-green, fluorescent siderophore (microbial iron transport agent) pseudobactin under iron-limiting conditions. A structural gene encoding the 85,000-Da putative outer membrane receptor protein for ferric pseudobactin was identified in a gene bank from Pseudomonas B10 prepared with the broad host-range conjugative cosmid cloning vector pLAFR1. Transposon Tn5 mutagenesis of recombinant plasmid pJLM300 localized the functional gene to a region of approximately 2.4 kilobases consistent with the apparent molecular weight of the receptor protein. Mobilization of pJLM300 into Pseudomonas A124 and A225, whose growth was inhibited by Pseudomonas B10 or pseudobactin, rendered these strains no longer susceptible to iron starvation by pseudobactin because they were now able to transport ferric pseudobactin. Pseudobactin biosynthetic genes flanked this receptor gene on both sides and were on separate operons. Transposon Tn5 insertion mutants of Pseudomonas B10 lacking this receptor protein were generated by a marker exchange technique and were defective in ferric pseudobactin transport. Such mutants could be complemented in trans by pJLM300. The production of pseudobactin, the receptor protein, and four other outer membrane proteins in Pseudomonas B10 was coordinately regulated by the level of intracellular iron.

Bacterial Proteins↗

PubMed1985

Effect of Pseudomonas contamination or antibiotic decontamination of the GI tract on acute radiation lethality after neutron or gamma irradiation.

The influence of antibiotic decontamination of Pseudomonas contamination of the GI tract prior to whole-body neutron or gamma irradiation was studied. It was observed that for fission neutron doses greater than 5.5 Gy, cyclotron-produced neutron doses greater than 6.7 Gy, and 137Cs gamma-ray doses greater than 14.4 Gy, the median survival time of untreated rats was relatively constant at 4.2 to 4.5 days, indicating death was due to intestinal injury. Within the dose range of 3.5 to 5.5 Gy of fission neutrons, 4.9 to 6.7 Gy of cyclotron-produced neutrons, and 9.6 to 14.4 Gy of gamma rays, median survival time of these animals was inversely related to dose and varied from 12 to 4.6 days. This change in survival time with dose reflects a transition in the mechanisms of acute radiation death from pure hematopoietic, to a combination of intestinal and hematopoietic, to pure intestinal death. Decontamination of the GI tract with antibiotics prior to irradiation increased median survival time 1 to 5 days in this transitional dose range. Contamination of the intestinal flora with Pseudomonas aeruginosa prior to irradiation reduced median survival time 1 to 5 days in the same radiation dose range. Pseudomonas-contaminated animals irradiated within this transitional dose range had maximum concentrations of total bacteria and Pseudomonas in their livers at the time of death. However, liver bacteria concentration was usually higher in gamma-irradiated animals, due to a smaller contribution of hematopoietic injury in neutron-irradiated animals. The effects of both decontamination of the GI tract and Pseudomonas contamination of the GI tract were negligible in the range of doses in which median survival time was dose independent, i.e., in the pure "intestinal death" dose range. Finally, despite the marked changes in survival time produced by decontamination or Pseudomonas contamination in the "transitional dose range," these treatments had little effect on ultimate survival after irradiation as measured by the LD50/5 day and the LD50/30 day end points. The implications of these results with respect to treatment of acute radiation injury after whole-body irradiation are discussed.

Animals↗

PubMed1986

Nosocomial outbreak of Pseudomonas aeruginosa folliculitis associated with a physiotherapy pool.

Outbreaks of community-acquired Pseudomonas aeruginosa folliculitis have recently been described in association with health spa whirlpools. In February 1984 we detected an outbreak of Pseudomonas folliculitis among hospital staff and patients using a swimming pool in a newly constructed physiotherapy unit. A rash developed in 5 (45%) of the 11 physiotherapists who had used the pool, as compared with 0 of the 17 who had not (p less than 0 005). Pseudomonas folliculitis also developed in 6 (21%) of 29 outpatients and 4 (33%) of 12 inpatients who had used the facility; Pseudomonas infection of a surgical wound also developed in 1 of the 4 inpatients. The epidemic curve was consistent with a continuing common-source outbreak. P. aeruginosa, serotype O:10, was isolated from three physiotherapists, the patient with an infected surgical wound and the pool. A case-control study of pool users did not identify risk factors for infection, although the physiotherapists had spent longer in the pool than had the patients. After hyperchlorination and structural repairs to the pool, no further cases were identified among pool users. This outbreak is the first reported nosocomial outbreak of Pseudomonas folliculitis. Further investigation is needed to determine the risk of serious Pseudomonas infections in hospitalized patients using physiotherapy pools.

Adult↗

PubMed1983

Role of complement in murine corneal infection caused by Pseudomonas aeruginosa.

The role of complement components C3 and C5 was examined in murine corneal infection induced by Pseudomonas aeruginosa. DBA/2 and Swiss-Webster mice are naturally resistant to experimental P. aeruginosa corneal infection. Mice of these two strains are able to restore a clear cornea within 4-6 weeks following Pseudomonas corneal challenge and are genetically deficient in the fifth component of complement. In contrast, ocular infection of congenic C5-deficient B10.D2o/Sn or normocomplementemic B10.D2n/Sn mice results in an identical pattern of susceptibility in which corneal perforation and phthisis bulbi occur. Taken together, these results indicate that C5 plays little or no role in susceptibility or resistance to Pseudomonas eye infection. In contrast, depletion of C3 in normally resistant DBA/2 mice using cobra venom factor (CoVF) diminishes the ability of these mice to restore a clear cornea following Pseudomonas infection. A single inoculation of CoVF, 24 hours prior to ocular challenge, is as effective in altering the response of DBA/2 mice as is continuous depletion of C3 during the course of infection using multiple inoculations of CoVF. Mice that are unable to clear Pseudomonas ocular infection following CoVF treatment regain this ability when the contralateral eye is infected after recovery of normal levels of C3. Depletion of C3 by CoVF treatment of DBA/2 mice, which had previously restored a clear cornea following Pseudomonas eye infection, again renders these mice susceptible.

Animals↗

PubMedDate not supplied

Pseudomonas respiratory infection in cystic fibrosis: a possible defect in opsonic IgG antibody?

Chronic Pseudomonas aeruginosa infections of the respiratory tract of people with cystic fibrosis (CF) usually are impossible to eradicate and greatly influence their health and longevity. General mechanisms of host defense are not impaired in this disease, except that serum does not support optimal phagocytosis of pseudomonas bacteria by alveolar macrophages and lung ciliary clearance is diminished, perhaps because of the accumulation of tenacious, purulent secretions in bronchiectatic airways and not by a defect in cilia structure or inhibitors of ciliary function. To investigate the defect in phagocytosis, we postulated that opsonic antibody might not be functioning well. Samples of purified IgG antibody against the typical strain of mucoid pseudomonas were prepared on immunoadsorbents, using CF sera and normal sera from volunteers previously immunized with a pseudomonas vaccine. CF IgG opsonin was found to agglutinate and coat well pseudomonas, but not to adhere or attach well to the surface of human alveolar macrophages, hence a defect in the function of the Fc portion of IgG was noted. In extending this analysis to CF lung secretions obtained by bronchoalveolar lavage, IgG antibody was purified exactly as from serum. Although this IgG had good agglutinating activity, much of it was fragmented (5 S size) and found to lack its Fc portion. It was evident that proteolytic enzymes in the purulent lavage secretions could cleave IgG. This activity was localized to a metallo-proteinase elaborated by the mucoid strain of pseudomonas. Thus, CF IgG may have reduced opsonic antibody function because of a molecular change in the Fc portion; this defect is magnified in the infected CF lung where a bacterial protease can actually fragment IgG and further impair its opsonic activity which is already marginal.

Cystic Fibrosis↗

PubMed1982

[Susceptibilities of Pseudomonas species to aminoglycosides and tetracyclines].

Pseudomonas aeruginosa has attracted much attention through its role in hospital outbreaks of disease. However, other members of the genus Pseudomonas, particularly Pseudomonas maltophilia and Pseudomonas cepacia, may be isolated as opportunistic pathogens of man, and can be found in hospital materials. These organisms have been less susceptible to the commonly used antibiotics. This report deals with the in vitro sensitivity of Pseudomonas strains except for P. aeruginosa to aminoglycosides and tetracyclines. The following bacteria were tested: P. maltophilia (50 strains), P. fluorescens (29 strains), P. putida (52 strains), P. cepacia (49 strains), P. putrefaciens (18 strains), P. acidovorans (12 strains). All of the strains for this study were isolated from routine cultures of infected clinical materials which sent to the Clinical Laboratories, Juntendo University Hospital during the 1 year period of 1980. The tests for susceptibility of the strains to the 3 aminoglycosides (gentamicin, tobramycin, amikacin) and 3 tetracyclines (tetracycline, doxycycline, minocycline) were all performed by the serial 2-fold agar plate dilution method on heart infusion agar, standardized by the Japan Society of Chemotherapy, using the microplanter apparatus with an inoculum size of approximately 10(8) CFU/ml. There were similar sensitivity patterns for the aminoglycosides tested; most of the strains of P. maltophilia, P. cepacia and P. acidovorans were resistant to the aminoglycosides, while most of P. fluorescens, P. putida and P. putrefaciens were sensitive. Minocycline and doxycycline were extremely active to the Pseudomonas species studied. Tetracycline was almost ineffective against P. maltophilia and P. cepacia.

Aminoglycosides↗

PubMed1983

Clinical significance of serum antibody responses to exotoxin A and type-specific lipopolysaccharides in patients with Pseudomonas aeruginosa infections.

Serum antibodies to Pseudomonas aeruginosa exotoxin A and immunotype-specific lipopolysaccharides were evaluated as diagnostic and prognostic markers in patients with Pseudomonas disease. Hemagglutination titers to exotoxin A were 1:1,024 or higher and/or showed a fourfold acute-to-convalescent increase in 17 of 25 (68 percent) patients infected with Pseudomonas compared with only one of seven (15 percent) colonized (p = 0.01) and two of 24 (8 percent) culture-negative patients (p less than 0.001). By comparison, hemagglutination titers to the lipopolysaccharide of patients' Pseudomonas isolates were 1:1,024 or higher or showed a fourfold increase in only four of 17 (24 percent) infected patients and in none of six (0 percent) colonized patients (p = 0.96). Serial antibody titers to exotoxin A provided serologic confirmation of invasive disease, distinguished infection from colonization, and, in the case of decreasing titers, indicated successful therapy. It is concluded that serum antibodies to exotoxin A are useful serologic markers for the clinical assessment of Pseudomonas infections in man.

ADP Ribose Transferases↗

PubMed2003

Genetic diversity and spoilage potentials among Pseudomonas spp. isolated from fluid milk products and dairy processing plants.

Degradation of milk components through various enzymatic activities associated with the contamination of dairy products by Pseudomonas spp. can reduce the shelf life of processed milk. Reliable methods for differentiating among Pseudomonas spp. strains are necessary to identify and eliminate specific sources of bacterial contamination from dairy processing systems. To that end, we assessed the genetic diversity and dairy product spoilage potentials among a total of 338 Pseudomonas spp. isolates from raw and pasteurized milk and from environmental samples collected from four dairy processing plants. The majority of isolates were identified as P. fluorescens and P. putida by API 20 NE. A total of 42 different ribotype patterns were identified among a subset of 81 isolates. The presence of many different ribotypes within this collection indicates high genetic diversity among the isolates and suggests multiple origins of contamination within the processing plant and in dairy products. The extracellular enzyme activity patterns among Pseudomonas isolates appeared to be associated with ribotypes. Isolates with the same ribotype frequently had the same extracellular protease, lecithinase, and lipase activities. For example, isolates grouped in ribotype 55-S-6 had the highest extracellular protease activity, while those in ribotypes 50-S-8 and 72-S-3 had the highest extracellular lipase activities. We conclude that ribotyping provides a reliable method for differentiating Pseudomonas strains with dairy food spoilage potential.

Animals↗

PubMed1969

Obtention and assay of rabbit anti-Pseudomonas serum.

Inoculation of rabbits with a nonliving anti-Pseudomonas vaccine induced appreciable levels of agglutinating antibodies against strains of P. aeruginosa included or not included in the vaccine. Serum obtained from vaccinated rabbits was able to confer temporary protection to mice against challenge with homologous or heterologous strains of Pseudomonas. When two or three doses of serum were used, all mice survived the challenge dose for more than 48 hr, but some of the animals died 10 days after challenge. When five doses of serum were used, all mice survived this 10-day period, and even 4 months later they did not show any sign of infection. Serum treatment temporarily inhibited Pseudomonas activity and allowed for the activation of the immunogenic mechanisms of the animals. This was corroborated by the fact that mice treated with three doses of serum and surviving the challenge dose for more than 20 days were immune against a second challenge. Anti-Pseudomonas gamma globulin conferred a lower degree of protection against homologous or heterologous strains of Pseudomonas.

Agglutination Tests↗

PubMed1997

Effects of BCL-2 overexpression on the sensitivity of MCF-7 breast cancer cells to ricin, diphtheria and Pseudomonas toxin and immunotoxins.

Immunotoxins are presently being evaluated as novel agents for cancer therapy. The direct mechanism by which immunotoxins kill cancer cells is inhibition of protein synthesis, but cytotoxicity due to induction of apoptosis has also been observed with these agents. Some cancers that express high levels of BCL-2 are relatively resistant to apoptosis inducing agents. It is therefore important to determine to what degree the toxicity of ricin, diphtheria toxin, Pseudomonas exotoxin and Pseudomonas exotoxin derived immunotoxins towards cancer cells can be attributed to inhibition of protein synthesis, and to what degree to subsequent induction of apoptosis. We compared the sensitivity of MCF-7 breast cancer cells that were stably transfected with a BCL-2 expression plasmid and thus protected against apoptosis and of MCF-7 cells transfected with a control plasmid towards ricin, diphtheria and Pseudomonas toxin, a Pseudomonas toxin-derived immunotoxin (LMB-7) and tumour necrosis factor alpha (TNF). We found that BCL-2 mediated inhibition of apoptosis renders the cells almost completely resistant (1000-fold) to tumour necrosis factor, but the same cells were only 3-10 fold more resistant to cytotoxicity induced by immunotoxin LMB-7 as well as Pseudomonas exotoxin, diphtheria toxin and ricin. We next studied several leukaemia cell lines with variable levels of BCL-2 expression and found them quite sensitive to a Pseudomonas exotoxin containing immunotoxin independent of the level of BCL-2. Our data indicate that although BCL-2 overexpression can have a modest effect on sensitivity to an immunotoxin, cell lines derived from patients are still very sensitive to immunotoxins.

Journal Article↗

PubMed1967

Dehydrogenase activity of pseudomonas species.

Single-strain cultures of Pseudomonas fragi, P. fluorescens, P. putrefaciens, and strains of two marine species, Pseudomonas type I and Pseudomonas type II, were found to be capable of reducing added acetaldehyde, proprionaldehyde, and butyraldehyde to the corresponding alcohols at 21 C. All species studied reduced propionaldehyde at 6 C. P. fragi, Pseudomonas type I, and Pseudomonas type II reduced butanone at 6 and 21 C. P. fragi and Pseudomonas type II reduced acetone at 21 C. Dehydrogenase activity was found in some cultures in which growth was not evident. Under aerobic conditions, a strain of P. fragi reduced added propionaldehyde to n-propanol quantitatively within 36 hr at 21 C.

Journal Article↗

PubMed1977

Fructose metabolism in four Pseudomonas species.

1. ATP-Dependent phosphorylation of fructose could not be detected in extracts of fructose-grown cells of Pseudomonas extorquens strain 16, Pseudomonas 3A2, Pseudomonas acidovorans and Pseudomonas fluorescens. Instead, phosphorylation of fructose to fructose-1-phosphate was found to occur when cell-free extracts were incubated with fructose and phosphoenolpyruvate. Such an activity could not be detected in cell-free extracts of succinate-grown cells. 2. High levels of 1-phosphofructokinase were found in extracts of the above organisms when growth on fructose. 3. Mutants of Pseudomonas extorquens strain 16 lacking 1-phosphofructokinase were unable to grow on fructose. Revertants to growth on fructose had regained the capacity to synthesize this enzyme, indicating its necessary involvement in fructose metabolism. 4. A survey has been carried out of enzymes involved in carbohydrate metabolism in the species listed above.

Cell-Free System↗

PubMedDate not supplied

Antibody determinations by counterimmunoelectrophoresis in the diagnosis and management of Pseudomonas aeruginosa bone and joint infections.

Antibody titers were measured by counterimmunoelectrophoresis in eight patients with Pseudomonas aeruginosa and in eight patients with Staphylococcus aureus bone and joint infections. Titers were obtained at the beginning of therapy in all patients with pseudomonas infections and at various intervals during and after completion of therapy in seven patients. These patients were followed clinically, with 99mTc-MDP bone and 67Ga scans, and with serial erythrocyte sedimentation rates. Six of eight of these patients had detectable pseudomonas antibodies. A fall in antibody titer occurred in all six successfully treated antibody-positive patients. By contrast, none of the control patients with staphylococcal infections had antibodies to pseudomonas heptavalent antigen. The predictive value of a positive test was 100% and of a negative test, 80%. Counterimmunoelectrophoresis is a helpful adjunctive test in supporting the diagnosis and documenting a successful treatment of chronic pseudomonas bone or joint infections.

Adult↗

PubMed1987

[Pseudomonas immunoglobulin prophylaxis in patients with burn injuries].

Pseudomonas aeruginosa belongs to the most frequent pathogens isolated from patients with burns. In a mouse model for artificial burns it was found that prophylactic administration of a hyperimmune globulin with antibody titres against P. aeruginosa (Fisher immunotypes 1, 2, 4 and 6) reduced mortality. Therefore, the prophylactic administration of Pseudomonas immunoglobulin was examined in a prospective randomized study in two groups of 13 patients each. Severely burned patients with at least second degree burns over 30% to 70% of the total body surface area received 250 mg Pseudomonas immunoglobulin/kg body weight by the intravenous route between days 3 and 13. After treatment, plasma IgG levels were significantly raised between days 7 and 16 as compared to the controls, yet the incidence of infections caused by P. aeruginosa was not reduced. However, only two of the six infected patients, developed septicaemia, whereas in the control group, local Pseudomonas infection led to septicaemia in five out of seven patients. The number of septicaemic Staphylococcus aureus infections was also lower in patients on immunoglobulin prophylaxis, with two cases compared to four cases in the control group. Due to the limited number of cases studied, statistically significant results could not be obtained, however, there was a positive trend in favour of Pseudomonas immunoglobulin treatment.

Adolescent↗

PubMedDate not supplied

[Prevention using a Pseudomonas immunoglobulin in burn patients].

Adolescent↗