Eleven new highly polymorphic microsatellite loci in the yellow croaker,Pseudosciaena crocea

We developed 11 new microsatellite markers in Pseudosciaena crocea by screening an enriched genomic library using nonradioactive polymerase chain reaction (PCR) techniques. All loci were found to be polymorphic with an average of 14.9 alleles per locus (range four to 30). The mean observed and expected heterozygosities were 0.86 (range 0.57–1.00) and 0.90 (range 0.62–0.98), respectively. Four loci showed significant Hardy–Weinberg disequilibrium. The high variabilities revealed in this study suggest that these microsatellite loci should provide useful markers for population genetic studies of P. crocea.     

Bioluminescence Activity and Degradation Kinetics of Genetically Engineered Strain P. putida mt-2 RB 1401 in Soil System with m-Xylene

Strain RB1401 contains a plasmid with a fusion between the upper pathway promoter of the TOL plasmid xyl genes and a lux gene cassette. Bioluminescence activity appeared in the early period of biodegradation of m-xylene, and was observed at all tested conditions of temperature (15, 27, 35°C) and pH (5, 7, 9), showing in the range of 300 ～ 6100 RLU. Biokinetics of strain RB1401 in the presence of m-xylene were as follows: Y 0.56 mg/mg, μ_max 2.67 day^-1, and K_s 19.25 mg/L. A ratio of C:N(KNO₃):P(KH₂PO₄) = 100:8:1.5 and 0.01% (w/v) of H₂O₂ were chosen for optimum biostimulation conditions of RB1401 with m-xylene in soil system. These results demonstrate the capability of such a genetically engineered bacteria for the development of biomonitoring and bioremediation in soil environments contaminated with specific volatile organic compounds.     

Lecithoceridae (Lepidoptera: Gelechioidea) of New Guinea,Part VIII: A new genus Sulciolus,with descriptions of two new species

As the eighth part in a series on the family Lecithoceridae (Lepidoptera: Gelechioidea) from New Guinea, Sulciolus Park, gen. nov. of the subfamily Lecithocerinae is described, based on the type species, S. pachystoma (Diakonoff), comb. nov., with two additional new species: (i) S. circulivalvae sp. nov.; and (ii) S. kaindiana sp. nov. The new genus shares with Achroa Meyrick, Onnuria Park, Hamatina Park and Scolizona Park a uniquely specialized 3rd segment of labial palpus, but it is differentiated from them by having a longitudinal furrow on the inner surface of the segment. Sulciolus abrasa (Diakonoff), S. capra (Diakonoff), S. induta (Diakonoff) and S. perspicua (Diakonoff) are newly combined, and Lecithocera sextacta Diakonoff is synonymized with S. perspicua (Diakonoff). Keys to genera related to Lecithocera and to species of the genus are given. Adults, labial palpi, wing venations and male genitalia are illustrated.     

High and low temperature tolerances and their relationships to distribution of agaves

Abstract. The potential influence of tissue tolerances to extreme temperatures on distributional limits was investigated for 15 taxa (14 species) of leaf-succulent agaves from the south-western United States and northern Mexico. As a group, the agaves exhibited a moderate low temperature tolerance of – 11°C (based on a 50% inhibition in the number of mesophyll cells taking up a stain, neutral red). However, nearly all of the species were able to tolerate extremely high tissue temperatures of over 60°C. Nocturnal acid accumulation by these crassulacean acid metabolism plants was about 6°C more sensitive to temperature extremes than was cellular membrane integrity.
High and low temperature acclimation in response to changing day/night air temperatures was observed in all 15 taxa, with high temperature acclimation averaging two-fold greater than low temperature acclimation (3.8°C versus 2.0°C per 10°C change in ambient temperature). Species occupying the coldest habitats exhibited the greatest low temperature tolerances and acclimation; several such species, such as Agave utahensis and A. schottii , had small rosette sizes which resulted in higher minimum leaf temperatures. Species from the hottest habitats had among the greatest high temperature tolerances and acclimation; the two species from open desert scrub habitats, A. deserti and A. lecheguilla , had the lowest leaf shortwave absorptances observed, which would result in lower maximum leaf temperatures. Thus morphology and tissue tolerances to stressful temperatures reflect the temperature extremes of a plant's native habitat, although low temperature tolerance appears to limit the distribution of agaves more than high temperature tolerance.     

Isolation and characterization of a cellulase-free endo-β-1,4-xylanase produced by an invertebrate-symbiotic bacterium, Cellulosimicrobium sp. HY-13

A xylanolytic bacterium, Cellulosimicrobium sp. HY-13, was isolated from the digestive tract of an earthworm, Eisenia fetida. The purified cellulase-free endo-β-1,4-xylanase (XylK) produced by strain HY-13 was found to contain an N-terminal amino acid sequence of APSTLEAAAE and to have a relative molecular mass of 36 kDa. It was most active at pH 6.0 and 55 °C and had V_max and K_m values toward oat spelt xylan of 4067 IU/mg and 2.78 mg/ml, respectively. XylK primarily degraded xylan to a series of xylooligosaccharides composed of xylobiose to xylotetraose, but it could not further hydrolyze xylobiose to xylose. The results of the present study suggest that the relatively highly active XylK lacking exo-xylanolytic activity is a promising candidate for the efficient production of non-digestible xylooligosaccharides that may have beneficial effects to gastrointestinal health via promotion of the growth of probiotics.     

Relationships between stream macroinvertebrates and environmental variables at multiple spatial scales

1. Aquatic communities are structured by multiple forces, and identifying the driving factors over multispatial scales is an important research issue. The East Asian monsoon region is globally one of the richest environments in terms of biodiversity, and is undergoing rapid human development, yet the river ecosystems in this region have not been well studied. We applied a hierarchical framework to incorporate regional and local environmental effects on stream macroinvertebrate communities in this region. The knowledge gained is expected to improve the understanding of the importance of spatial scale on regional and local diversity in the East Asian monsoon region. 2. A national data set of benthic macroinvertebrates and environmental variables (geographical, land‐use, hydrological, substratum and physicochemical elements) in Korean rivers was used to determine the habitat preferences of macroinvertebrates. 3. Latitude, proportion of forest coverage, riffle habitat, silt substratum and temperature were the most important determinants for the ordinations of macroinvertebrate communities in each category evaluated by canonical correspondence analysis (CCA). The optimal habitats for stream macroinvertebrates are not the same for all species, and overall community metrics and abundance of sensitive species tended to be lower in open agricultural and urban streams than in forested streams. The sensitivity of mayflies and stoneflies to anthropogenic disturbances implicated them as good indicators to assess the effects of urban and agricultural activities. 4. A partial CCA was used to evaluate the relative importance of macrohabitat and microhabitat variables on community composition at three spatial scales (whole country, the large Han River basin and two small sub‐basins in the lowlands and highlands). The majority of community variation (17–22% for each environmental element) was explained by macrohabitat variables at the regional spatial scale. In contrast, large proportions (15–18%) were explained by microhabitat variables at the local spatial scale. 5. Our findings indicate that the relative importance of habitat scales should be determined by geographical size and that comprehensive understanding of multispatial scale patterns can be important for implementing sound biodiversity conservation programmes.     

Description of a new Homidia species (Collembola,Entomobryidae) from Korea

A new species, Homidia pseudoformosana from Korea is described in the present paper. The new species is characterized by labral papillae, ciliated labial seta L₁ and dorsal chaetotaxy of abdominal segment IV. The detailed differences between similar Homidia species are provided.