DNA homology and adsorption specificity of Pseudomonas aeruginosa virulent bacteriophages

Summary The DNA homology and adsorption specificity of newly isolated virulent bacteriophages of P. aeruginosa have been studied. On the basis of this analysis all phages were divided into four groups: k, m, mnP78-like and mnF82-like bacteriophages. DNA's of k as well as m phages were shown to possess different restriction patterns although they have an extensive homology. Unlike other groups, k phages were characterized by the presence of T4 DNA ligase-repaired, single-chain breaks.Abbreviations kbp kilobase pairs - EM electron microscopy     

Cloning of genes degrading 3-chlorobenzoate from Pseudomonas putida strain 87]

The ability of Pseudomonas putida strain 87 to catabolize 3-chlorobenzoate was shown to be mediated by genes of pBS109 plasmid. The plasmid may be transferred by conjugation into P. aeruginosa PAO2175. It seems possible that the pBS109 plasmid codes for pyrocatechase II specific for halogenated catechol, but not catechol. The genes specifying utilization of 3-chlorobenzoate from pBS109 plasmid were cloned in the 5.5 kb BgIII fragment by using broad-host cloning system. The resulting pBS110 plasmid was transferred into P. putida, which results in utilization of 3-chlorobenzoate by transconjugants.     

Characteristics of plasmid pBS271 controlling epsilon-caprolactam degradation by bacteria in the genus Pseudomonas

Conjugative plasmids control the ability of five Pseudomonas strains isolated from the rectifiers of chemical plants to grow on epsilon-caprolactam as a sole carbon and nitrogen source. All the plasmids have a high molecular mass of their DNA (ca. 300 MDa) and control epsilon-caprolactam degradation at least to succinate. One of the plasmids (pBS271) belongs to the incompatibility group P-2 and suppresses the growth of a broad spectrum of temperate and virulent P. aeruginosa bacteriophages as well as that of some P. putida bacteriophages.     

Dual-channel microfluorometer-photometer based on standard block assemblies and units

The principles of construction and methods of practical realizing of double-wave microfluorometers-photometers for investigation of molecular processes in cells and cell populations are considered.     

Severe Painful Vaso-Occlusive Crises and Mortality in a Contemporary Adult Sickle Cell Anemia Cohort Study

Background

Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.

Methods

Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.

Results

Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.

Conclusions

Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.

Trial Registration

ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/     

Increased production of the protein antigen of Brucella melitensis in Escherichia coli K-12 cells

The production of Brucella melitensis protein antigen with molecular weight of 38 kD in Escherichia coli K-12 cell lysates has been studied by immunoblotting with various antisera. E. coli strains differed by the vector plasmid and the size of B. melitensis 565 DNA fragment with 38 kD protein gene, cloned in this plasmid. The immunoblotting analysis detected increased production of 38 kD protein in the recombinant GSE830 strain in comparison with the B. melitensis strain 565, from which the gene was cloned, and other E. coli strains containing this protein gene. The production of 38 kD protein was determined by the size of the cloned B. melitensis 565 DNA fragment with this protein gene, but not by the conditions of culturing.