Assignment of Alteromonas elyakovii KMM 162T and five strains isolated from spot-wounded fronds of Laminaria japonica to Pseudoalteromonas elyakovii comb. nov. and the extended description of the species. (1/47)

A marine bacterium, Alteromonas elyakovii KMM 162T, which was described recently, and five strains isolated from spot-wounded fronds of Laminaria japonica have been subjected to phylogenetic analysis, and geno- and phenotypic characterization. The phenotypic features of Pseudoalteromonas elyakovii strains were closely related to that of Pseudoalteromonas espejiana IAM 12640T, but utilization of three carbon compounds (D-mannose, L-tyrosine and trehalose) distinguished both species. The G+C content of Pseudoalteromonas elyakovii was between 38.5 and 38.9 mol%. Pseudoalteromonas elyakovii KMM 162T and the five Laminaria isolates constitute a single species different from any other Alteromonas and Pseudoalteromonas species as revealed by DNA-DNA hybridization data, especially Pseudoalteromonas distincta KMM 638T (52.4%), Pseudoalteromonas citrea KMM 216 (49.5%), Pseudoalteromonas carrageenovora NCIMB 302T (46.9%) and Pseudoalteromonas espejiana IAM 12640T (29.9%). All the data indicated that Alteromonas elyakovii KMM 162T should be reclassified as Pseudoalteromonas elyakovii and five strains isolated from Laminaria japonica have to be included in the species. Pseudoalteromonas elyakovii comb. nov. (type strain, KMM 162T = ATCC 700519T) is proposed and a set of phenotypic features which differentiate the Pseudoalteromonas species is described.  (+info)

Preparation of the cervix for surgical termination of pregnancy in the first trimester. (2/47)

Worldwide, surgical vacuum aspiration is the method of choice of terminating first trimester unwanted pregnancy. Cervical priming prior to surgical evacuation reduces the risks of cervical injury by making the cervix softer and easier to dilate. Over the years, a number of effective methods of cervical priming have became available: osmotic dilators; antiprogesterone and prostaglandins. Of these, prostaglandins remain the most widely used method of cervical preparation. However many of the natural and synthetic analogues of prostaglandins are either expensive or associated with troublesome side-effects. More recently, misoprostol, a synthetic 15-deoxy-16 hydroxy 16-methyl analogue of naturally occurring prostaglandin E, used in the management of peptic ulcers, has established a lead for cervical priming in terms of availability, ease of administration, cost and effectiveness. In fact it appears that both oral and vaginal misoprostol given at dosages of 400 microg are effective for cervical priming when administered 3 h prior to surgical vacuum aspiration. Now that the use of misoprostol for cervical priming has been validated, its widespread use in gynaecological practice is expected.  (+info)

Oligoguluronates elicit an oxidative burst in the brown algal kelp Laminaria digitata. (3/47)

Oligomeric degradation products of alginate elicited a respiratory and oxidative burst in the sporophytes of the kelp Laminaria digitata. The generation of activated oxygen species (AOS), O(2)(-), and H(2)O(2) was detected at the single cell level, using nitroblue tetrazolium precipitation and a redox-sensitive fluorescent probe, respectively. The oxidative burst involved diphenyleneiodonium-sensitive AOS-generating machinery and its amplitude depended on the type of tissue. After a first elicitation plants were desensitized for about 3 h. The activity of alginate oligosaccharides was dose dependent, saturating around 40 microM. It was also structure-dependent, with homopolymeric blocks of alpha-1,4-L-guluronic acid, i.e. the functional analogs of oligogalacturonic blocks in pectins, being the most active signals. The perception of oligoguluronate signals resulted in a strong efflux of potassium. Pharmacological dissection of the early events preceding the emission of AOS indicated that the transduction chain of oligoguluronate signals in L. digitata is likely to feature protein kinases, phospholipase A(2), as well as K(+), Ca(2+), and anion channels.  (+info)

Reaction of acylated homoserine lactone bacterial signaling molecules with oxidized halogen antimicrobials. (4/47)

Oxidized halogen antimicrobials, such as hypochlorous and hypobromous acids, have been used extensively for microbial control in industrial systems. Recent discoveries have shown that acylated homoserine lactone cell-to-cell signaling molecules are important for biofilm formation in Pseudomonas aeruginosa, suggesting that biofouling can be controlled by interfering with bacterial cell-to-cell communication. This study was conducted to investigate the potential for oxidized halogens to react with acylated homoserine lactone-based signaling molecules. Acylated homoserine lactones containing a 3-oxo group were found to rapidly react with oxidized halogens, while acylated homoserine lactones lacking the 3-oxo functionality did not react. The Chromobacterium violaceum CV026 bioassay was used to determine the effects of such reactions on acylated homoserine lactone activity. The results demonstrated that 3-oxo acyl homoserine lactone activity was rapidly lost upon exposure to oxidized halogens; however, acylated homoserine lactones lacking the 3-oxo group retained activity. Experiments with the marine alga Laminaria digitata demonstrated that natural haloperoxidase systems are capable of mediating the deactivation of acylated homoserine lactones. This may illustrate a natural defense mechanism to prevent biofouling on the surface of this marine alga. The Chromobacterium violaceum activity assay illustrates that reactions between 3-oxo acylated homoserine lactone molecules and oxidized halogens do occur despite the presence of biofilm components at much greater concentrations. This work suggests that oxidized halogens may control biofilm not only via a cidal mechanism, but also by possibly interfering with 3-oxo acylated homoserine lactone-based cell signaling.  (+info)

Isolation and enzymatic characterization of lamjapin, the first ribosome-inactivating protein from cryptogamic algal plant (Laminaria japonica A). (5/47)

Lamjapin, a novel type Iota ribosome-inactivating protein, has been isolated from kelp (Laminaria japonica A), a marine alga. This protein has been extensively purified through multiple chromatography columns. With a molecular mass of approximately 36 kDa, lamjapin is slightly larger than the other known single-chain ribosome-inactivating proteins from the higher plants. Lamjapin can inhibit protein synthesis in rabbit reticulocyte lysate with an IC50 of 0.69 nm. It can depurinate at multiple sites of RNA in rat ribosome and produce the diagnostic R-fragment and three additional larger fragments after the aniline reaction. Lamjapin can deadenylate specifically at the site A20 of the synthetic oligoribonucleotide (35-mer) substrate that mimics the sarcin/ricin domain (SRD) of rat ribosomal 28S RNA. However, it cannot hydrolyze the N-C glycosidic bond of guanosine, cytidine or uridine at the corresponding site of the A20 of three mutant SRD RNAs. Lamjapin exhibits the same base and position requirement as the ribosome-inactivating proteins from higher plants. We conclude that lamjapin is an RNA N-glycosidase that belongs to the ribosome-inactivating protein family. This study reports for the first time that ribosome-inactivating protein exists in the lower cryptogamic algal plant.  (+info)

The brown algal kelp Laminaria digitata features distinct bromoperoxidase and iodoperoxidase activities. (6/47)

Different haloperoxidases, one specific for the oxidation of iodide and another that can oxidize both iodide and bromide, were separated from the sporophytes of the brown alga Laminaria digitata and purified to electrophoretic homogeneity. The iodoperoxidase activity was approximately seven times more efficient than the bromoperoxidase fraction in the oxidation of iodide. The two enzymes were markedly different in their molecular masses, trypsin digestion profiles, and immunological characteristics. Also, in contrast to the iodoperoxidase, bromoperoxidases were present in the form of multimeric aggregates of near-identical proteins. Two full-length haloperoxidase cDNAs were isolated from L. digitata, using haloperoxidase partial cDNAs that had been identified previously in an Expressed Sequence Tag analysis of the life cycle of this species (1). Sequence comparisons, mass spectrometry, and immunological analyses of the purified bromoperoxidase, as well as the activity of the protein expressed in Escherichia coli, all indicate that these almost identical cDNAs encode bromoperoxidases. Haloperoxidases form a large multigenic family in L. digitata, and the potential functions of haloperoxidases in this kelp are discussed.  (+info)

Characterization of mannuronan C-5-epimerase genes from the brown alga Laminaria digitata. (7/47)

Alginate is an industrially important polysaccharide obtained commercially by harvesting brown algae. The final step in alginate biosynthesis, the epimerization of beta-1,4-d-mannuronic acid to alpha-1,4-l-guluronic acid, a structural change that controls the physicochemical properties of the alginate, is catalyzed by the enzyme mannuronan C-5-epimerase. Six different cDNAs with homology to bacterial mannuronan C-5-epimerases were isolated from the brown alga Laminaria digitata (Phaeophyceae). Hydrophobic cluster analysis indicated that the proteins encoded by the L. digitata sequences have important structural similarities to the bacterial mannuronan C-5-epimerases, including conservation of the catalytic site. The expression of the C-5-epimerase genes was examined by northern-blot analysis and reverse transcriptase-polymerase chain reaction in L. digitata throughout a year. Expression was also monitored in protoplast cultures by northern and western blot, reverse transcriptase-polymerase chain reaction, and activity measurements. From both the structural comparisons and the expression pattern, it appears that the cDNAs isolated from L. digitata encode functional mannuronan C-5-epimerases. The phylogenetic relationships of the bacterial and brown algal enzymes and the inferences on the origin of alginate biosynthetic machinery are discussed.  (+info)

Two cases of anaphylaxis after laminaria insertion. (8/47)

Anaphylaxis following laminaria insertion rarely occurs but may be a life-threatening condition. Laminaria tents, prepared from natural sea kelp, are commonly used prior to elective termination of pregnancy to achieve cervical dilatation. We report herein two cases of anaphylaxis caused by IgE-mediated hypersensitivity to laminaria. Two women, each of whom had undergone at least one previous abortion where a laminaria had been utilized, developed anaphylactic reaction following laminaria insertion. The reaction included urticaria, nausea, breathing difficulty, and hypotension. The patients subsequently underwent skin testing and measurement of serum specific IgE level to laminaria extract, and were shown to elicit positive responses to laminaria. The implication and impact of laminaria allergy on gynecologic procedures are significant and this allergy should be included in the list of differential diagnoses for hypersensitive reaction in gynecologic procedures.  (+info)

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