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L Baumann

Publications and source records attributed to L Baumann.

At least 55 records · Page 3Linked to original sources
PubMed1988

Sequence analysis of the mosquitocidal toxin genes encoding 51.4- and 41.9-kilodalton proteins from Bacillus sphaericus 2362 and 2297.

The nucleotide sequences of a 3,479-base-pair HindIII DNA fragment from Bacillus sphaericus 2362 and a 2,940-base-pair fragment from strain 2297 were determined; only minor differences were detected between them. Each contained two open reading frames coding for proteins of 51.4 and 41.9 kilodaltons. Both proteins were required for toxicity to larvae of the mosquito Culex pipiens.

Amino Acid Sequence↗
PubMed1988

Erythromycin therapy for subclinical intrauterine infections in threatened preterm delivery--a preliminary report.

Evidence suggests that subclinical intrauterine infections which can be indicated by elevated maternal CRP-values may cause preterm labor and that Ureaplasma urealyticum might play a role in the pathogenesis of preterm delivery. Since these organisms are sensitive to erythromycin, 43 patients with threatened preterm labor were at the time of tocolysis treated with erythromycin, or placebo in a randomized study. Treatment with erythromycin resulted in a greater mean delay of delivery for 9 days than among the placebo-treated women. This effect is statistically significant in patients with intact membranes and cervical dilatation: in contrast to the placebo group these women achieved an increased delay of 23 days before delivering. Moreover, successful erythromycin treatment was significantly associated with the isolation of ureaplasmas from vaginal swabs. Our results emphasize that in cases with cervical dilatation, vaginal microorganisms, especially ureaplasmas, are more liely to ascend and might be involved in the initiation of preterm labor. Therefore, additional treatment with erythromycin was beneficial only in these women.

Erythromycin↗
PubMed1987

Cloning of the gene for the larvicidal toxin of Bacillus sphaericus 2362: evidence for a family of related sequences.

During sporulation, Bacillus sphaericus 2362 produces a parasporal crystalline protein which is toxic for the larvae of a number of mosquito species. Using the Escherichia coli cloning vector lambda gt11, in which gene products of the inserts may be fused to beta-galactosidase, we isolated 29 bacteriophages which produced peptides-reacting with antiserum to crystal protein. On the basis of restriction enzyme analyses of the recombinants and Ouchterlony immunodiffusion experiments with induced lysogens as a source of antigens, the recombinants were assigned to three groups, designated A, B, and C. Group A consisted of three clones which appeared to express all or part of the B. sphaericus toxin gene from their own promoters and one clone producing a beta-galactosidase-toxin fusion protein. The host cells of two induced recombinant lysogens of this group were toxic to larvae of Culex pipiens. A cell suspension containing 174 ng (dry weight) of the more toxic recombinant per ml killed 50% of the larvae. Both recombinants formed peptides with molecular sizes of 27, 43, and 63 kilodaltons (kDa). The antigenically related 27- and 43-kDa peptides were distinct from the 63-kDa peptide, which resembled crystals from sporulating cells of B. sphaericus in which antigenically distinct 43- and 63-kDa proteins are derived from a 125-kDa precursor. A 3.5-kilobase HindIII fragment from recombinants having toxic activity against larvae was subcloned into pGEM-3-blue. E. coli cells harboring this fragment were toxic to mosquito larvae and produced peptides of 27, 43, and 63 kDa. The distribution of the A gene among strains of B. sphaericus of different toxicities suggested that it is the sole or principal gene encoding the larvicidal crystal protein. The two recombinants of group B and the 23 of group C were all beta-galactosidase fusion proteins, suggesting that in E. coli these genes were not readily expressed from their own promoters. The distribution of these two genes in different strains of B. sphaericus suggested that they do not have a role in the toxicity of this species to mosquito larvae.

Animals↗
PubMed1987

[Clinical value of determining C-reactive protein in the maternal serum in pregnancies with threatened premature labor].

In this article, because of the importance of subclinical infections for triggering premature labor, we have investigated the maternal serum levels of C-reactive protein (CRP) in 88 pregnancies with comparable gestational ages at the onset of premature birth symptoms. We found certain associations between possible prolongation of gestation by tocolysis and absence or presence of pathologic values of this acute-phase-protein. Positive CRP-values are associated with significantly lowered prolongation of pregnancy by tocolysis and subsequently lowered gestational age at birth. Though there are no correlations to maternal temperature and white blood cell counts, antenatal CTG-results, amniotic fluid properties and parameters of the neonate, we found probable relations to the detection of Ureaplasmas in the vaginal swabs. Once more we point out to possible associations between mycoplasmas and premature birth.

C-Reactive Protein↗
PubMed1986

[Infections with penicillinase-producing Neisseria gonorrhoeae in females. Report on 24 cases].

Between the last few weeks of 1980 and March 1985 the susceptibilities of 881 strains of Neisseria gonorrhoeae to penicillin were tested by a simple screening method (disc diffusion test). 76.6% of the isolates were good susceptible, 17.7% moderately susceptible and 5.7% resistant to 3 units of penicillin G. Penicillinase-producing Neisseria gonorrhoeae (PPNG) could be detected in 24 cases (2.7%), most of them between July 1983 and January 1984 (n = 18). 23 patients have been treated successfully with oxytetracycline. All infections had been acquired in the GDR, however, the sources of infection could be firmly traced in 6 cases only. On the basis of the results some clinical and microbiological aspects of infections with penicillin resistant gonococci are discussed.

Adolescent↗
PubMed1985

Purification of the larvicidal toxin of Bacillus sphaericus and evidence for high-molecular-weight precursors.

Crystals were purified from spore-crystal complexes of Bacillus sphaericus 2362 by disruption in a French pressure cell followed by centrifugation through 48% (wt/vol) NaBr. Crystals from such preparations had a 50% lethal concentration of 6 ng of protein per ml for the larvae of the mosquito Culex pipiens. When subjected to polyacrylamide gel electrophoresis under denaturing conditions, the proteins in B. sphaericus crystals migrated in positions corresponding to 43, 63, 98, 110, and 125 kilodaltons (kDa); solubilization of the crystal at pH 12 with NaOH eliminated all but the bands at 43 and 63 kDa. Since NaOH-solubilized preparations were toxic to mosquito larvae, these proteins were purified to electrophoretic homogeneity and antiserum was obtained to each. Analysis of the two purified proteins indicated that the 43-kDa protein was toxic to mosquito larvae (50% lethal concentration, 35 ng of protein per ml), whereas the 63-kDa protein was not. Further differences between them were their amino acid compositions, their lack of immunological cross-reactivity, their opposite net charges at pH 7.5, and their susceptibility to digestion by larval midgut proteases (the 63-kDa protein was highly susceptible, whereas the 43-kDa protein was not). The sequence of the 40 N-terminal residues of the 43-kDa protein was determined and found to contain a high percentage of hydrophobic amino acids. The sequence of the 63-kDa protein could not be determined, since it had multiple N termini. By electrophoretically separating the crystal proteins and then electroblotting onto nitrocellulose paper and visualizing the bands with antisera to the 43- and 63-kDa proteins in conjunction with an immunoblot assay, it was found that the high-molecular-mass crystal proteins (98 to 125 kDa) contained antigenic determinants of both proteins. These results suggested that the lower-molecular-weight crystal proteins detected in polyacrylamide gels after electrophoresis under denaturing conditions were derivatives of one or more of the higher-molecular-weight crystal proteins. In vivo studies of the products of crystal degradation by larvae of Culex pipiens indicated that the high-molecular-weight proteins and the 63-kDa antigenic determinants were rapidly degraded and that a 40-kDa protein related to the 43-kDa toxin persisted for the duration of the experiment (4 h). Some of the studies performed with B.sphaericus 2362 were extended to strains 1593, 1691, and 2297 of this species with results which indicated a high degree of similarity between the crystal proteins of all these larvicidal strains.

Amino Acid Sequence↗
PubMed1982

[Results and experience with the diagnosis of Neisseria gonorrhoeae].

Between January 1978 and August 1981, 4,708 examinations for detection of Neisseria gonorrhoeae were carried out at the Gynaecological Hospital of Karl-Marx Universität Leipzig. Certain aspects relating to laboratory diagnosis of gonorrhoea are expounded, against the findings obtained from these examinations.--Culturing yield was increased by the factor of 2.6, from 4.8 per cent (1978/1979) to 12.3 per cent (1980/1981) by improvement of culturing media. Substrate quality proved to be essential to effectiveness of culturing.--Most of the above examinations, relating to 45 per cent of all positive cases, had been performed for adnexitis. The cervix was confirmed to be the most useful site from which to take swabs. Eighty-five per cent of gonococcal strains isolated in 1980 and 1981 were sufficiently responsive to penicillin. Beta-lactamase formers were not recorded. Methods and culturing media are described in some detail.

Female↗
PubMed1978

Studies of relationship among terrestrial Pseudomonas, Alcaligenes, and enterobacteria by an immunological comparison of glutamine synthetase.

Antibody to purified glutamine synthetase from Escherichia coli was prepared and used for an immunological comparison of glutamine synthetases from species of Salmonella, Citrobacter, Enterobacter, Serratia, Proteus, Erwinia, Aeromonas, Pseudomonas, Acinetobacter, Xanthomonas, Alcaligenes, and Paracoccus. The results of Ouchterlony double diffusion experiments and quantitative microcomplement fixation studies indicated that the amino acid sequence of this enzyme was highly conserved in different organisms. The order of relationship to E. coli was found to be similar to that derived from immunological investigations of other enzymes. In addition, congruence was observed between ribosomal RNA homology and the results of the microcomplement fixation experiments. The results also suggested that some species of Alcaligenes were more closely related to species of Pseudomonas than to each other. Immunological comparisons of glutamine synthetases appear to be very useful for the elucidation of relationships among distantly related species and genera.

Alcaligenes↗
PubMed1977

Pathways of D-fructose and D-glucose catabolism in marine species of Alcaligenes, Pseudomonas marina, and Alteromonas communis.

Cell-free extracts of D-fructose grown cells of marine species of Alcaligenes as well as Pseudomonas marina contained an activity which catalyzed a P-enolpyruvate-dependent phosphorylation of D-fructose in the 1-position as well as activities of the following enzymes: 1-P-fructokinase, fructose-1,6-P2 aldolase, PPi-dependent 6-P-fructokinase, fructokinase, glucokinase, P-hexose isomerase, glucose-6-P dehydrogenase, 6-P-gluconate dehydrase, and 2-keto-3-deoxy-6-P-gluconate aldolase. The presence of these enzyme activites would allow D-fructose to be degraded by the Embden-Meyerhof pathway and/or the Entner-Doudoroff pathway. In cell-free extracts of D-glucose grown cells, the activity catalyzing a P-enolpyruvate-dependent phosphorylation of D-fructose as well as 1-P-fructokinase activity were reduced or absent while the remaining enzymes were present at levels similar to those found in D-fructose grown cells. Radiolabeling experiments suggested that both D-fructose and D-glucose were utilized primarily via the Entner-Doudoroff pathway. Alteromonas communis, a marine species lacking 1-P-fructokinase and the PPi-dependent 6-P-fructokinase, contained all the enzyme activites necessary for the catabolism of D-fructose and D-glucose by the Entner-Doudoroff pathway; the involvement of this pathway was also consitent with the results of the radiolabeling experiments.

Alcaligenes↗
PubMed1977

Pathways of D-fructose catabolism in species of Pseudomonas.

Cell-free extracts of D-fructose grown cells of Pseudomonas putida, P. fluorescens, P. aeruginosa, P. stutzeri, P. mendocina, P. acidovorans and P. maltophila catalyzed a P-enolpyruvate-dependent phosphorylation of D-fructose and contained 1-P-fructokinase activity suggesting that in these species fructose-1-P and fructose-1,6-P2 were intermediates of D-fructose catabolism. Neither the 1-P-fructokinase nor the activity catalyzing a P-enolpyruvate-dependent phosphorylation of D-fructose was present in significant amounts in succinate-grown cells indicating that both activities were inducible. Cell-free extracts also contained activities of fructose-1,6-P2 aldolase, fructose-1,6-P2 phosphatase, and P-hexose isomerase which could convert fructose-1,6-P2 to intermediates of either the Embden-Meyerhof pathway or Entner-Doudoroff pathway. Radiolabeling experiments with 1-14C-D-fructose suggested that in P. putida, P. aeruginosa, P. stutzeri, and P. acidovorans most of the alanine was made via the Entner-Doudoroff pathway with a minor portion being made via the Embden-Meyerhof pathway. An edd- mutant of O. putida which lacked a functional Entner-Doudoroff pathway but was able to grow on D-fructose appeared to make alanine solely via the Embden-Meyerhof pathway.

Alanine↗
PubMed1976

Study of genetic relationships among marine species of the genera Beneckea and Photobacterium by means of in vitro DNA/DNA hybridization.

Strains representative of species of the marine genera Beneckea and Photobacterium were used as reference standards in in vitro DNA/DNA competition experiments. Within a given species, strains were found to be related by over 80% competition. (Competition was defined as the amount of radioactive DNA displaced by heterologous DNA relative to the amount displaced by homologous DNA.) On the basis of interspecies competition values (expressed as averages), the following groupings could be made: 1. "Photobacterium" fischeri was related to strain ATCC 15382 by a competition of 38% and was distinct from all the other strains tested (competition less than or equal to 11%). 2. The genus Photobacterium consisted of 3 species, P.phosphoreum, P.leiognathi, and a newly designated species, P.angustum (composed of non-luminous strains). The latter species was found to be related to P.leiognathi and P.phosphoreum by 56 and 28% competition, respectively, while P.phosphoreum was related to P.leiognathi by 29%. 3. In the genus Beneckea, 65% competition was detected between B.harveyi and B.campbellii as well as between B.parahaemolytica and B.alginolytica. These pairs of species were related to each other by 51-58% and to B.natriegens by 34-56% competition. A newly designated pathogenic species, B.vulnifica, appeared to have a low but significant relationship to all the above mentioned species of Beneckea. 4. Two biotypes, related by 68% competition, were recognized in the species B.splendida. Similarly, B.pelagia was found to consist of 2 biotypes related by a competition of 67%. The competition values between these species were 38-40%. 5. B.nereida, B.nigrapulchrituda, and "Vibrio" anguillarum had competition values less than or equal to 30% to each other as well as to other species of Beneckea. 6. With Vibrio cholerae as the reference standard, V.albensis was found to be related by a competition of 82%, while V.proteus and V.metschnikovii had competition values of 22 and 12%, respectively. These results suggested that V.albensis should be synonymized with V.cholerae, while the latter two organisms should remain distinct from this species. V.cholerae as well as the other terrestrial organisms tested did not appear to be significantly related to any of the marine strains (competition values less than or equal to 27%). The speciation derived from the results of the DNA/DNA competition experiments was compared to previous speciation based on phenotypic similarities.

DNA, Bacterial↗