A new guaianolide as apoptosis inhibitor from Chrysanthemum boreale

The 8-O-acetyl-3,10-dihydroxy-4(15),11(13)-guaiadien-12,6-olide, named borenolide, was isolated from Chrysanthemum boreale M. Borenolide inhibits the etoposide-induced apoptosis in U937 cell with an IC(50) value of 6.2 microg/ml. Structural assignment was based on NMR-spectroscopic methods and X-ray crystallographic analysis.

Planomicrobium koreense gen. nov., sp. nov., a bacterium isolated from the Korean traditional fermented seafood jeotgal, and transfer of Planococcus okeanokoites (Nakagawa et al. 1996) and Planococcus mcmeekinii (Junge et al. 1998) to the genus Planomicrobium

A bacterial strain, JG07T, isolated from the Korean traditional fermented seafood jeotgal, was subjected to a polyphasic taxonomic study. Cells of strain JG07T are cocci or short rods in the early growth phase but change to rods as the cultures age. The peptidoglycan type is A4alpha, based on L-Lys-D-Glu. The menaquinone profile is characterized by the predominance of MK-8 followed by MK-7 and MK-6. The cellular fatty acid profile contains major amounts of saturated, unsaturated and branched fatty acids. The cellular phospholipids are phosphatidylethanolamine, phosphatidylglycerol and bisphosphatidylglycerol. The G+C content of the DNA is 47 mol%. Phylogenetic analysis showed that strain JG07T forms a cluster with Planococcus okeanokoites and Planococcus mcmeekinii, and the relationship between this cluster and two other Planococcus species described previously is supported by bootstrap analysis at a confidence level of 100%. The 16S-23S internally transcribed spacer (ITS) sequence similarity and DNA-DNA relatedness values between strain JG07T and the type strains of other Planococcus species are in the range 74.6-83.2% and 10.4-20.5%, respectively. On the basis of the phenotypic and phylogenetic data and the genomic distinctiveness, strain JG07T is considered to represent a new genus and a new species, for which the name Planomicrobium koreense gen. nov., sp. nov. is proposed. It is also proposed that Planococcus okeanokoites and Planococcus mcmeekinii be transferred to the new genus Planomicrobium as Planomicrobium okeanokoites and Planomicrobium mcmeekinii, respectively.

Bacillus jeotgali sp. nov., isolated from jeotgal, Korean traditional fermented seafood

Two Gram-variable, rod-shaped, endospore-forming bacterial strains, which are motile with peritrichous flagella, were isolated from a Korean traditional fermented seafood, jeotgal. The two isolates (strains YKJ-1OT and YKJ-11) were proven to be members of the same species on the basis of the results of phenotypic and phylogenetic analyses and DNA relatedness. Strains YKJ-10T and YKJ-11 were characterized by having cell wall peptidoglycan based on meso-diaminopimelic acid, MK-7 as the predominant menaquinone, and iso-C15:0 as the major fatty acid. The G+C content of the DNA was 41 mol%. Strains YKJ-10T and YKJ-11 showed only a 1 bp sequence difference in the 16S rDNA sequences. The two strains formed distinct phylogenetic lineages within the radiation of the cluster comprising Bacillus species. Levels of 16S rDNA similarity between strains YKJ-10T and YKJ-11 and Bacillus species were less than 96.6%. Levels of DNA-DNA relatedness were found to be low enough to distinguish strains YKJ-10T and YKJ-11 from some phylogenetically related Bacillus species. On the basis of phenotypic properties, phylogeny and genomic distinctiveness, strains YKJ-10T and YKJ-11 represent a new species of the genus Bacillus, for which a new name, Bacillusjeotgali sp. nov., is proposed. The type strain of the new species is strain YKJ-10T (= KCCM 41040T = JCM 10885T).

Halomonas marisflavae sp. nov., a halophilic bacterium isolated from the Yellow Sea in Korea

A halophilic Gram-negative bacterial strain, SW32T, which was isolated from a sample from the Yellow Sea of Korea, was subjected to a polyphasic taxonomic study. This organism grew optimally in the presence of 0.5-12% NaCl. On the basis of phenotypic and phylogenetic data, strain SW32T appeared to be a member of the genus Halomonas. Strain SW32T formed a distinct evolutionary lineage within the phylogenetic clade comprising Halomonas species and the genera Zymobacter and Carnimonas. The 16S rDNA sequence of strain SW32T contains 19 signature characteristics of the genus Halomonas and the family Halomonadaceae. Strain SW32T possessed a single polar flagellum, ubiquinone-9 as the predominant respiratory lipoquinone and C18:1, C16:0 and C16:1 omega7c and/or iso-C15:0 20H as the major fatty acids. The DNA G+C content was 59 mol%. Levels of 16S rDNA similarity between strain SW32T and the type strains of all validly described Halomonas species were 92.0-93.8%. Strain SW32T exhibited 16S rDNA similarity values of 92.7% to Zymobacter palmae IAM 14233T and 91.6% to Carnimonas nigrificans CECT 4437T. These data indicate that strain SW32T was related enough to members of the genus Halomonas to be placed as a new species within that genus. Therefore the name Halomonas marisflavae sp. nov. is proposed for strain SW32T. The type strain of the new species is strain SW32T (= KCCM 80003T = JCM 10873T).

Sporosarcina aquimarina sp. nov., a bacterium isolated from seawater in Korea, and transfer of Bacillus globisporus (Larkin and Stokes 1967), Bacillus psychrophilus (Nakamura 1984) and Bacillus pasteurii (Chester 1898) to the genus Sporosarcina as Sporosarcina globispora comb. nov., Sporosarcina psychrophila comb. nov. and Sporosarcina pasteurii comb. nov., and emended description of th

A light-orange-coloured, facultatively anaerobic, rod-shaped bacterium (strain SW28T), which was isolated from seawater in Korea, was taxonomically studied by a polyphasic approach. This organism formed round terminal endospores in swollen sporangia. The peptidoglycan type is A4alpha, based on L-Lys-L-Ala-D-Asp. The predominant menaquinone is MK-7 and the major fatty acid is ante-C15:0. The G+C content of the DNA is 40 mol%. Phylogenetic analysis based on 16S rDNA sequences showed that strain SW28T falls within the radiation of a cluster comprising the rRNA group 2 bacilli and non-Bacillus-type organisms. Strain SW28T showed the highest degree of relatedness to the type strain of Sporosarcina ureae, sharing 96.8% 16S rDNA similarity. Levels of DNA-DNA relatedness between strain SW28T and S. ureae DSM 2281T and the type strains of some Bacillus species forming a coherent phylogenetic cluster are less than 12.5%. On the basis of phenotypic and chemotaxonomic characteristics, 16S rDNA sequence analysis and DNA-DNA relatedness data, it is proposed that strain SW28T should be placed in the genus Sporosarcina as a new species, Sporosarcina aquimarina sp. nov. The type strain is SW28T (= KCCM 41039T = JCM 10887T). From the results of the taxonomic re-evaluation, it is also proposed that Bacillus globisporus, Bacillus psychrophilus and Bacillus pasteurii be transferred to the genus Sporosarcina as Sporosarcina globispora, Sporosarcina psychrophila and Sporosarcina pasteurii, respectively.

Pharmacotherapeutic options in inflammatory bowel disease: an update

Chronic inflammatory bowel disease (IBD) refers to two diseases: Crohn's disease (CD) and ulcerative colitis (UC). The etiology of IBD remains unknown. The understanding of the pathogenesis has expanded greatly over the last decade. The combination of genetic risk factors, abnormalities in the immune system, vascular and neural factors, and random environmental factors may all play an important role. Most treatments currently in use have multiple action. The choice of appropriate medical treatment is determined by the status (inductive or maintenance therapy) and severity of the disease and the potential for toxicity. Despite the variety of medical therapies available for the treatment of IBD, none is ideal. Ongoing research into the well-established drugs, as well as novel agents with more precise targets, may contribute to an optimal therapy of IBD in the near future. In this paper the current (5-aminosalicylates, glucocorticosteroids, thioguanine derivatives, methotrexate, cyclosporin and infliximab) as well as some of the new (mycophenolate mofetil and thalidomide) therapeutic options are reviewed.

Rhodococcus pyridinivorans sp. nov., a pyridine-degrading bacterium

The taxonomic position of a bacterial strain (PDB9T) that is capable of degrading pyridine was clarified by a polyphasic taxonomic approach using phenotypic, chemotaxonomic and genetic methods. The cells, which are rods and branched filaments during the early growth phase, fragment into short rods or cocci, thereby completing the growth cycle. Strain PDB9T was found to have a cell wall of chemotype IV, MK-8(H2) as the predominant menaquinone, mycolic acids with 36-46 carbon atoms and C16:0' C18:1 cis9, 10-methyl-C18:0 (TBSA) as the major fatty acids. The G+C content of the DNA was 66 mol%. The phylogenetic tree showed that strain PDB9T falls within an evolutionary radiation comprising Rhodococcus species and is most closely related to the type strain of Rhodococcus rhodochrous, sharing 99% 16S rDNA similarity. The differences in some phenotypic characteristics and the genetic distinctiveness distinguish strain PDB9T from the Rhodococcus species described previously. Therefore, strain PDB9T should be placed in the genus Rhodococcus as a new species, for which the new name Rhodococcus pyridinivorans sp. nov. is proposed. The type strain of the new species is strain PDB9T (= KCTC 0647BPT = KCCM 80005T).

Janibacter terrae sp. nov., a bacterium isolated from soil around a wastewater treatment plant

A bacterial strain, CS12T, which was isolated from soil around a wastewater treatment plant, was subjected to a polyphasic taxonomic study using phenotypic characterizations and genetic methods. The cell wall of strain CS12T contains meso-diaminopimelic acid as the diamino acid but no arabinose and galactose. The predominant menaquinone is MK-8(H4). Mycolic acids are absent. Strain CS12T has a cellular fatty acid profile containing saturated, unsaturated, branched and 10-methyl fatty acids. The major fatty acids are iso-C16:0, C18:1 omega9c and anteiso-C17:0, The G+C content is 69 mol%. A phylogenetic tree based on 16S rDNA sequences showed that strain CS12T forms an evolutionary lineage within the radiation enclosing the members of the family Intrasporangiaceae and, in particular, a coherent cluster with Janibacter limosus DSM 11140T. The level of 16S rDNA similarity between strain CS12T and J. limosus DSM 11140T is 98.7%. The phenotypic characteristics and DNA-DNA relatedness data indicate that strain CS12T should be distinguished from J. limosus DSM 11140T. Therefore, on the basis of the data presented, a new species of the genus Janibacter, Janibacter terrae, is proposed. The type strain of the new species is strain CS12T (= KCCM 80001T = JCM 10705T).

Lactobacillus kimchii sp. nov., a new species from kimchi

A bacteriocin-producing lactic acid bacterium, which was isolated from the Korean fermented-vegetable food kimchi, was subjected to a polyphasic taxonomic study using phenotypic characterization and phylogenetic and genetic methods. This organism (MT-1077T) has phenotypic properties that are consistent with the description characterizing the genus Lactobacillus. Phylogenetic analysis based on 16S rDNA sequences showed clearly that strain MT-1077T is a member of the genus Lactobacillus. The closest phylogenetic relatives are Lactobacillus alimentarius KCTC 3593T and Lactobacillus farciminis LMG 9200T, with levels of 16S rDNA similarity of 98.4 and 98.2%, respectively. Levels of 16S rDNA similarity between strain MT-1077T and other Lactobacillus species were less than 93.0%. Differences in some phenotypic characteristics and DNA-DNA relatedness data indicated that strain MT-1077T should be distinguished from L. alimentarius KCTC 3593T and L. farciminis LMG 9200T. On the basis of the data presented, it is proposed that strain MT-1077T should be placed in the genus Lactobacillus as a new species, Lactobacillus kimchii sp. nov. The type strain of the new species is strain MT-1077T (= KCTC 8903PT = JCM 10707T).

MR566A and MR566B, new melanin synthesis inhibitors produced by Trichoderma harzianum. II. Physico-chemical properties and structural elucidation

New melanin synthesis inhibitors (MR566A and B) and six related known isocyanocyclopentenes were isolated from the fermentation broth of Trichoderma harzianum, and their structures were elucidated by spectroscopic methods. The structures of novel isocyanides, MR566A (1) and B (2), were elucidated as 1-(3-chloro-1,2-dihydroxy-4-isocyano-4-cyclopenten-1-yl)etha nol, 1-(1,2,3-trihydroxy-3-isocyano-4-cyclopenten-1-yl)ethanol, respectively. The structure of novel oxazole, MR93B (9), was elucidated as 4-[(1Z)-3-hydroxy-2-hydroxymethyl-1-propen-1-yl]oxazole.

MR566A and MR566B, new melanin synthesis inhibitors produced by Trichoderma harzianum. I. Taxonomy, fermentation, isolation and biological activities

New melanin synthesis inhibitors (MR566A and B) and six related known isocyanocyclopentenes were isolated from the fermentation broth of Trichoderma harzianum. The IC50 values of MR566A and B against mushroom tyrosinase were 1.72 and 47 microM, respectively. They inhibited melanin biosynthesis in B16 melanoma cells with MIC values of 0.1 and 2.2 microM, respectively. Also isolated from the same culture extract of T. harzianum was a new oxazole (MR93B), which showed no inhibitory activity against mushroom tyrosinase at a concentration of 1,000 microg/ml.

The Drosophila tumor suppressor gene, dlg, is involved in structural plasticity at a glutamatergic synapse

BACKGROUND

Synaptic contacts between neurons and their targets are dynamic entities that can change depending on developmental and functional states of the pre- and postsynaptic cell. However, the molecular factors involved in this plasticity have remained largely unknown. We have demonstrated previously that the Drosophila tumor suppressor gene, discs-large (dlg), is expressed at neuromuscular synapses, and is required for normal synapse structure. A family of dlg homologues is also expressed at mammalian synapses, where they interact with the N-methyl-D-aspartate receptor and ion channels. Here, we provide the first demonstration of the involvement of dlg in structural synaptic plasticity during postsynaptic target growth.

RESULTS

We used a temperature-sensitive dlg allele to demonstrate that there are two stages, late embryogenesis and larval stages, at which dlg is necessary for normal formation of synapses. These stages are coincident with dynamic DLG expression at presynaptic sites in the late embryo, and at postsynaptic regions in the larva. Ultrastructural and confocal analyses reveal that Drosophila neuromuscular junctions undergo a dramatic expansion of the postsynaptic apparatus, which is paralleled by target muscle growth. We show that this process of postsynaptic expansion is partially blocked in dlg mutants.

CONCLUSIONS

Our results demonstrate that dlg is required during synapse maturation. We show that dlg is involved in the determination of postsynaptic size during target muscle growth. Because motoneuron targets in the larva are continuously growing, synaptic contacts are structurally plastic, undergoing continuous expansion. We conclude that dlg plays an important role in this form of structural synaptic plasticity.

Bestatin analogue from Streptomyces neyagawaensis SL-387

A bestatin analogue, (2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-valine (AHPA-Val), from the culture filtrate of Streptomyces neyagawaensis SL-387 was obtained in a chemically defined medium containing DL-3-amino-3-phenylpropionic acid. AHPA-Val was 6 times (IC50 = 1.2 micrograms/ml) as strong as bestatin (IC50 = 7.0 micrograms/ml) against porcine kidney microsomal aminopeptidase N, and 4 times (5.6 micrograms/ml) as strong as bestatin (IC50 = 20.7 micrograms/ml) against aminopeptidase N of human metastatic fibrosarcoma HT1080. To the best of our knowledge, this is the first report on the microbial production of AHPA-Val.

Suprageneric classification of peptidoglycan group B actinomycetes by nucleotide sequencing of 5S ribosomal RNA

5S ribosomal RNA sequences were determined for thirteen actinomycetes mainly representatives with the rare group B type peptidoglycan. The primary and secondary structure of the resultant sequences were of the type characteristic of Gram-positive bacteria with DNA rich in guanine plus cytosine. The sequencing and associated chemotaxonomic data provide compelling grounds for classifying actinomycetes with a group B type peptidoglycan in a single family. The family Microbacteriaceae fam. nov. is proposed to accommodate actinomycetes classified in the genera Agromyces, Aureobacterium, Clavibacter, Curtobacterium and Microbacterium.

Domain structure and multiplicity of raw-starch-digesting amylase from Bacillus circulans: extensive proteolysis with proteinase K, endopeptidase Glu-C and thermolysin

Raw-starch-digesting amylase (RSDA) is a key extracellular enzyme of mesophilic Bacillus circulans F-2 which uses raw starch granules as a carbon source. Previous work has demonstrated that there are two domains of the enzyme during digestion with subtilisin, and that RSDA activity is selectively inactivated by limited proteolysis with subtilisin, which cleaves the enzyme between these hydrolytic and adsorption domains (Kim, C.-H., Kwon, S.-T., Taniguchi, H. and Lee, D.-S. (1992) Biochim. Biophys. Acta 1122, 243-250). In this work we show that a similar phenomenon is observed during limited proteinase K, thermolysin and endopeptidase Glu-C proteolysis of the enzyme. Fragments resulting from proteolysis were characterized by immunoblotting with anti-RSDA. The proteolytic patterns resulting from proteinase K and subtilisin were the same, producing 63 and 30-kDa fragments. Similar patterns were obtained with endopeptidase Glu-C or thermolysin. All proteolytic digests contained a common, major 63-kDa fragment. Inactivation of RSDA activity results from splitting off the C-terminal domain. Hence, it seems probable that the proteinase-sensitive locus is in a hinge region susceptible to cleavage. Extracellular enzymes immunoreactive towards anti-RSDA were detected through whole bacterial cultivation. 93, 75, 63, 55, 38 and 31-kDa proteins were immunologically identical to RSDA. Of these, the 75-kDa and 63-kDa proteins correspond to the major products of proteolysis with Glu-C and thermolysin. These results suggest that enzyme heterogeneity of the raw-starch hydrolysis system might arise from the endogenous proteolytic activity of the bacterium.

Gene organization and primary structure of a ribosomal RNA gene cluster from Streptomyces griseus subsp. griseus

The Streptomyces griseus subsp. griseus KCTC 9080 genome contains six rRNA-encoding gene (rDNA) clusters. One rDNA cluster (rrnE), contained in an 8.7-kb BamHI fragment, was cloned and sequenced. The rDNA were arranged in the order 16S-23S-5S, and separated by small intergenic spacers. No tRNA-encoding sequences were found in the spacer regions. The lengths of the mature 16S, 23S and 5S rRNAs were 1528, 3120 and 120 nucleotides (nt), respectively. The G + C content of the gene cluster was lower than that of the chromosomal DNA. In general, the primary and secondary structures of the three rRNAs showed good agreement with those from other Streptomyces species. However, in comparison with Escherichia coli, two noticeable changes (mismatches and deletions) and two large insertions were identified in the 16S and 23S rRNAs, respectively. On the other hand, regions showing considerable heterogeneity, even within the genus Streptomyces, were found in both rRNAs. Putative primers and processing signals showing high sequence similarity to those from other Streptomyces species were located in the region upstream from the 5' end of the mature 16S rRNA. A potential hairpin loop structure reminiscent of a Rho-independent terminator was located just downstream from the 5S rRNA. A considerable degree of sequence conservation and variation within rDNA gene clusters was revealed in this study, both at the infra- and suprageneric levels.

Suprageneric classification of thermoactinomyces vulgaris by nucleotide sequencing of 5S ribosomal RNA

The 5S rRNA nucleotide sequence of Thermoactinomyces vulgaris was determined and compared with published sequences of representative Gram-positive bacteria. The primary and secondary structure of the sequence is of the type characteristic of Gram-positive bacteria that have DNA with a low proportion of guanine plus cytosine. It was evident from the phylogenetic trees that T. vulgaris has little in common with actinomycetes but is related to the genus Bacillus, showing a moderately high relationship with B. stearothermophilus. The taxonomic implications of these relationships are discussed and an emended description of the family Bacillaceae is given.

Classification of acidophilic, neutrotolerant and neutrophilic streptomycetes by nucleotide sequencing of 5S ribosomal RNA

Complete 5S ribosomal RNA sequences were obtained for four acidophilic actinomycetes, seven neutrophilic streptomycetes and a strain of Streptoverticillium baldaccii. All of the organisms contained RNAs belonging to the 120 nucleotide type. An evolutionary tree was generated after combining the test data with results from similar studies on representative Gram-positive bacteria. The acidophilic, neutrotolerant and neutrophilic actinomycetes were recovered in a distinct cluster that was equated with the genus Streptomyces. The sequence data support the view that the genera Chainia, Elytrosporangium, Kitasatoa and Microellobosporia should be considered as synonyms of the genus Streptomyces. The recovery of the Streptoverticillium baldaccii strain on the fringe of the Streptomyces cluster is also consistent with current trends in the taxonomy of these organisms. Further work is needed to determine the taxonomic status of the two streptomycete subgroups that comprised the streptomycete cluster.

Kinetic studies of the thermal decomposition of 2-chloroethylphosphonic Acid in aqueous solution

The decomposition of 2-chloroethylphosphonic acid in aqueous solution has been studied at pH values from 6 to 9 and at temperatures in the 30 to 55 C range. The rate of decomposition is estimated from the rate of formation of ethylene. The rate is proportional to the concentration of the phosphonate dianion and is independent of the hydroxyl ion concentration. The rate constant at 40 C is 1.9 x 10(-4) sec(-1) and the activation energy is 29.8 kcal mol(-1). The rate of reaction is not affected significantly by the presence of potassium iodide or urea (substances which increase the rate of leaf abscission in trees sprayed by 2-chloroethylphosphonic acid). The rate decreases slightly in the presence of low concentrations of magnesium and calcium ions.