Lytic β-1,3 Glucanase from Arthrobacter: Pattern of Action

The action pattern of lytic β-1,3 glucanase (glucanase I) from Arthrobacter which liberates predominantly laminaripentaose from various β-glucans has been studied. The enzyme was not active on short linear laminaridextrins, but was active on an enzymatically synthesized, linear β-1,3 oligoglucan preparation. Any intactness of the glucose residues of the chain ends of a substrate did not seem to be necessary for the action of the enzyme. The results of determination of laminaripentaose during a relatively early phase of the reaction suggested that about half of the reducing power liberated in the medium might be explained by the formation of the sugar. It seems that the formation of laminaripentaose relates to the initial attack of glucanase 1 on β-1,3 glucan chains.     

Interactive Effects of Viral and Bacterial Production on Marine Bacterial Diversity

A general model of species diversity predicts that the latter is maximized when productivity and disturbance are balanced. Based on this model, we hypothesized that the response of bacterial diversity to the ratio of viral to bacterial production (VP/BP) would be dome-shaped. In order to test this hypothesis, we obtained data on changes in bacterial communities (determined by terminal restriction fragment length polymorphism of 16S rRNA gene) along a wide VP/BP gradient (more than two orders of magnitude), using seawater incubations from NW Mediterranean surface waters, i.e., control and treatments with additions of phosphate, viruses, or both. In December, one dominant Operational Taxonomic Unit accounted for the major fraction of total amplified DNA in the phosphate addition treatment (75±20%, ± S.D.), but its contribution was low in the phosphate and virus addition treatment (23±19%), indicating that viruses prevented the prevalence of taxa that were competitively superior in phosphate-replete conditions. In contrast, in February, the single taxon predominance in the community was held in the phosphate addition treatment even with addition of viruses. We observed statistically robust dome-shaped response patterns of bacterial diversity to VP/BP, with significantly high bacterial diversity at intermediate VP/BP. This was consistent with our model-based hypothesis, indicating that bacterial production and viral-induced mortality interactively affect bacterial diversity in seawater.     

Monitoring records of plant species in the Hakone region of Fuji-Hakone-Izu National Park, Japan, 2001–2010

The monitoring of species occurrences is a crucial aspect of biodiversity conservation, and regional volunteerism can serve as a powerful tool in such endeavors. The Fuji-Hakone-Izu National Park in the Hakone region of Kanagawa Prefecture, Japan, boasts a volunteer association of approximately 100 members. These volunteers have monitored plant species occurrences from 2001 to the present along several hiking trails in the region. In this paper, I present the annual observation records of plant occurrences in Hakone from 2001 to 2010. This data set includes 1,071 species of plants from 151 families. Scientific names follow the Y List, and this data set includes several threatened plant species. Data files are formatted based on the Darwin Core and Darwin Core Archives, which are defined by the Biodiversity Information Standards (BIS) or Biodiversity Information Standards Taxonomic Databases Working Group (TDWG). Data files filled on required and some additional item on Darwin Core. The data set can download from the author’s personal Web site as of July 2012. These data will soon be published for the Global Biodiversity Information Facility (GBIF) through GBIF Japan. All users can then access the data from the GBIF portal site.     

A New H-Phosphonate Approach Using N-Unprotected Monomers and Phosphonium Condensing Reagents

Abstract

Oligodexyribonucleotides were synthesized by using N-unprotected H-phosphonate monomers and a phosphonium-type of new condensing reagent. In the present H-phosphonate approach, N-sulfonyloxaziridine derivatives were successfully employed as new reagents for oxidation of the H-phosphonate linkages in the presence of silylating reagents.     

Isolation and Identification of Gibberellins A4 and A9 from a Fungus Phaeosphaeria sp.

Quinolactacide isolated from Penicillium citrinum F 1539 was synthesized and evaluated for its insecticidal activities. The key steps of the total synthesis were an acyl migration reaction of the enol ester intermediate and dehydrogenation of tetrahydroquinolactacide with manganese dioxide. The synthesized quinolactacide showed 100% and 42% mortality against the green peach aphid (Myzus persicae) and diamondback moth (Plutella xylostella) at 500 ppm, respectively.     

Temporal Variability of Preferred Illuminance Self-Selected by Women during Wakefulness

The primary purpose of this study was to test our hypothesis that the behavior of self-selecting the preferred ambient illuminance might be determined by a load error between the core temperature and its set-point. Seven female volunteers were asked to choose the preferred ambient light intensity by adjusting a rheostat from the time when they rose spontaneously in the morning to the time when they felt sleepy and retired. Rectal temperature was measured every 10 min. Their preferred ambient light intensity increased quickly and then gradually after they rose and rose to approximately 2000 lx over 3 hrs. It decreased gradually and then quickly to the time when they retired. We discussed these findings in terms of a load error between the actual core temperature and its set-point.