Halocynthiibacter namhaensis gen. nov., sp. nov., a novel alphaproteobacterium isolated from sea squirt Halocynthia roretzi

A Gram-negative, non-motile and rod-shaped bacterial strain, designated RA2-3^T, was isolated from a sea squirt (Halocynthia roretzi) collected from the South Sea, Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain RA2-3^T was observed to grow optimally at 25 °C, at pH 7.0–7.5 and in the presence of 2 % (w/v) NaCl. Strain RA2-3^T exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Litoreibacter meonggei (95.7 %), Planktotalea frisia (95.6 %), Thalassobius gelatinovorus (95.5 %) and Pelagicola litoralis (95.4 %). A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain RA2-3^T clustered with the type strains of Planktotalea frisia, Pelagicola litoralis, Pacificibacter maritimus and Roseovarius marinus. Strain RA2-3^T was found to contain Q-10 as the predominant ubiquinone and C_18:1 ω7c as the major fatty acid. The major polar lipids detected in strain RA2-3^T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain RA2-3^T was 52.9 mol%. On the basis of the phylogenetic, chemotaxonomic and phenotypic properties, strain RA2-3^T is considered to represent a new genus and species within the family Rhodobacteraceae, for which the name Halocynthiibacter namhaensis gen. nov., sp. nov. is proposed. The type strain of H. namhaensis is RA2-3^T (=KCTC 32362^T=NBRC 109999^T).     

Levels of viral glycoprotein provide a dose-dependent measure of tumor cell inhibition

A chemosensitivity assay utilizing small replicate Mm5mt/c1 C3H mammary tumor cell cultures was developed to determine whether changes in viral antigen expression and release into culture fluids could be utilized as an in vitro measure of chemotherapeutic drug effect. The 52,000 MW viral envelope glycoprotein (gp52) of the mouse mammary tumor virus (MMTV) was measured in culture fluids of control and drug-treated cultures while cell density was simultaneously determined by cell staining and OD 664 mu determination. While extracellular gp52 levels and cell density both progressively increased over 72 hours for control cultures, treatments with doxorubicin resulted in dose-dependent declines in both parameters at 24, 48, and 72 hours. Comparison of doxorubicin dosages for 50% reduction (ED50s) in both parameters (0.68uM and 1.1uM) revealed a similar coordinate reduction in both cell density and MMTVgp52. When gp52 levels were further examined as a general measure of effect for a broad spectrum of 6 drugs with differing mechanisms of action, coordinate declines in cell density and MMTVgp52 provided a time and dose-dependent dual measure of effect for each of the drugs tested. Coordinate declines resulted in the same following hierarchy of concentration-dependent drug potency: methotrexate greater than 5-fluorouracil greater than doxorubicin greater than N [phosphonacetyl- L aspartic acid] (PALA) greater than cis-platinum greater than cyclophosphamide. The dual measures of therapeutic effect afforded by this assay argue for its use as an in vitro measure of effect for optimizing drug treatments.     

Ruegeria arenilitoris sp. nov., isolated from the seashore sand around a seaweed farm

A Gram-negative, motile and rod-shaped bacterial strain, G-M8^T, which was isolated from seashore sand around a seaweed farm at Geoje island in South Korea, was characterized taxonomically. It grew optimally at 30–37 °C, at pH 7.0–8.0 and in presence of 2 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain G-M8^T joined the cluster comprising the type strains of Ruegeria atlantica and Ruegeria lacuscaerulensis, showing 97.5 % sequence similarity, by a bootstrap resampling value of 85.8 %. It exhibited 16S rRNA gene sequence similarity values of 95.4–96.7 % to the type strains of the other Ruegeria species. Strain G-M8^T exhibited the highest gyrB sequence similarity value (88.5 %) to the type strain of R. lacuscaerulensis. Strain G-M8^T contained Q-10 as the predominant ubiquinone and C_18:1 ω7c as the predominant fatty acid. The polar lipid profile of strain G-M8^T was similar to that of R. atlantica KCTC 12424^T. The DNA G+C content of strain G-M8^T was 64.6 mol% and its mean DNA–DNA relatedness values with R. atlantica KCTC 12424^T and R. lacuscaerulensis KCTC 2953^T were 18 ± 5.3 and 10 ± 3.6 %, respectively. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, demonstrated that strain G-M8^T is distinguished from other Ruegeria species. On the basis of the data presented, strain G-M8^T (=KCTC 23960^T = CCUG 62412^T) represents a novel species of the genus Ruegeria, for which the name Ruegeria arenilitoris sp. nov. is proposed.     

Comparative petiole anatomy of the tribe Sorbarieae (Rosaceae) provide new taxonomically informative characters

We conducted a comparative anatomical study of the petiole of 16 taxa belonging to the tribe Sorbarieae (Rosaceae) (Adenostoma, 2 spp.; Chamaebatiaria, 1 sp.; Sorbaria, 6 spp., 3 vars., and 1 forma; and Spiraeanthus, 1 sp.) and the related genus Lyonothamnus (1 sp. and 1 ssp.). The distal, medial and proximal regions of petioles were transversely sectioned using conventional embedding and staining methods. Cuticles, crystals, trichomes and pericyclic fiber patterns were observed and studied. Three types of vascular nodal patterns were recognized: Type 1 was seen in Chamaebatiaria, Lyonothamnus, and Spiraeanthus (simple‐trace nodal pattern with slightly curved or U‐shaped vascular bundle); type 2 was found in Adenostoma (multiple‐traces nodal pattern with free vascular bundles); and type 3 was unique to Sorbaria (bundles fused to form a siphonostele nodal pattern). Some petiolar anatomical characteristics (e.g. cuticles, crystals, trichomes, vascular nodal pattern, and pericyclic fiber patterns) were found to provide useful information for taxonomic studies within Sorbarieae. On the basis of these characteristics, a dichotomous key for identification at the generic/specific level is provided. We also report a structural change in the vascular bundles from the stem‐leaf transitional zone to the leaf medial zone.     

<Emphasis Type="Italic">Arcobacter acticola</Emphasis> sp. nov., isolated from seawater on the East Sea in South Korea

A Gram-stain-negative, facultative aerobic, non-flagellated, and rod-shaped bacterium, designated AR-13^T, was isolated from a seawater on the East Sea in South Korea, and subjected to a polyphasic taxonomic study. Strain AR-13^T grew optimally at 30°C, at pH 7.0–8.0 and in the presence of 0–0.5% (w/v) NaCl. The phylogenetic trees based on 16S rRNA gene sequences showed that strain AR-13^T fell within the clade comprising the type strains of Arcobacter species, clustering coherently with the type strain of Arcobacter venerupis. Strain AR-13^T exhibited 16S rRNA gene sequence similarity values of 98.1% to the type strain of A. venerupis and of 93.2–96.9% to the type strains of the other Arcobacter species. Strain AR-13^T contained MK-6 as the only menaquinone and summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), C_16:0, C_18:1ω7c, and summed feature 2 (iso-C_16:1 I and/or C_14:0 3-OH) as the major fatty acids. The major polar lipids detected in strain AR-13^T were phosphatidylethanolamine, phosphatidylglycerol, and one unidentified aminophospholipid. The DNA G+C content was 28.3 mol% and its mean DNA-DNA relatedness value with the type strain of A. venerupis was 21%. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain AR-13^T is separated from recognized Arcobacter species. On the basis of the data presented, strain AR-13^T is considered to represent a novel species of the genus Arcobacter, for which the name Arcobacter acticola sp. nov. is proposed. The type strain is AR-13^T (=KCTC 52212^T =NBRC 112272^T).     

Identification and monitoring of Korean medicines derived from <Emphasis Type="Italic">Cinnamomum</Emphasis> spp. by using ITS and DNA marker

In this study, we identified and evaluated the genetic relationships among Cinnamomum plants, which are used in traditional medicine. We also attempted to monitor the distribution of traditional medicines derived from Cinnamomum cassia by using DNA barcoding and a species-specific DNA marker. Plants of the genus Cinnamomum, and in particular C. cassia, are commonly used as medicinal herbs in the form of Cinnamomi Ramulus, Cinnamomi Cortex, and Cassiae Cortex Interior. However, it is difficult to distinguish among different Cinnamomum species based on morphological features, and so to overcome this limitation, nucleotide sequences of the internal transcribed spacer (ITS) region of Cinnamomum DNA were determined and compared. On the basis of the discrepancy in determined ITS sequences, a 408-bp product, amplified by the primer pair CC F1/CC R3, was developed as a C. cassia-specific DNA marker. Using the developed DNA marker in combination with the ITS 2 nucleotide sequence, we monitored imported and commercially supplied medicinal products derived from Cinnamomum plants in markets in Korean, China, and Japan. The results revealed that most of the specimens monitored were derived from C. cassia.     

Synthesis of biflavones having a 6-O-7’’ linkage and effects on cyclooxygenase-2 and inducible nitric oxide synthase

In order to establish anti-inflammatory potential of biflavonoids, 17 biflavone derivatives having a 6-O-7″ linkage were synthesized and their effects on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were evaluated. The basic molecule (6-O-7″ biflavone) potently inhibited COX-2-mediated PGE₂ production (IC₅₀: < 2 μM), being less active on iNOS-mediated NO production (IC₅₀: > 50 μM) from lipopolysaccharide-treated RAW 264.7 cells, a mouse macrophage cell line. Generally, the hydroxyl/methoxyl substitution(s) on the basic biflavone (6-O-7″) reduced the inhibitory activity of PGE₂ production, while the effects on NO production were varied. It is suggested that the basic biflavone (6-O-7″) may have a potential for new anti-inflammatory agent.     

Identification of compounds exhibiting inhibitory activity toward the Pseudomonas tolaasii toxin tolaasin I using in silico docking calculations,NMR binding assays,and in vitro hemolytic activity assays

Using in silico docking calculations, NMR analysis of target–ligand binding, and hemolytic activity assays, we searched a 30,000-compound library for an effective inhibitor of tolaasin I, a Pseudomonas tolaasii toxin that causes virulent infection in mushrooms. Of more than 30,000 compounds screened in silico, two compounds were selected. One of these compounds, sorbitololeic acid, bound to tolaasin I and inhibited its hemolytic activity in vitro. Therefore, sorbitololeic acid can be a potential inhibitor of tolaasin I.