Purification and Some Properties of Lignostilbene-a,/i-dioxygenase Responsible for the Ca—Cp Cleavage of a Diarylpropane Type Lignin Model Compound from Pseudomonas sp. TMY1009

A novel dioxygenase, lignostilbene-a,β-dioxygenase (LSD), which catalyzes cleavage of the interphenyl double bond of lignin-derived stilbenes, was isolated. Four isozymes of LSD were separated from cell-free extracts of Pseudomonas sp. TMY1009 by ion-exchange chromatography on a DEAE- Toyopearl column. The major isozyme, LSD-I, was purified to electrophoretic homogeneity and characterized.

LSD-I cleaved the interphenyl double bond of l,2-bis(4′-hydroxy-3′-methoxyphenyl)ethylene with the optimum pH at 8.5. The Km of LSD-I was 11 μm for the stilbene and 110/iM for oxygen. The molecular weight of LSD-I, which is composed of two identical subunits, was estimated to be 94,000. LSD-I contained 1 g atom of iron per 1 mol of enzyme protein.     

Highly enantioselective asymmetric autocatalysis of 2-alkenyl- and 2-vinyl-5-pyrimidyl alkanols with significant amplification of enantiomeric excess

2-Alkenyl- and 2-vinyl-5-pyrimidyl alkanols are highly enantioselective asymmetric autocatalysts with significant amplification of enantiomeric excess in the enantioselective addition of diisopropylzinc to 2-alkenyl- and 2-vinylpyrimidine-5-carbaldehydes. Consecutive asymmetric autocatalysis starting from 7% ee increases the ee of pyrimidyl alkanol up to 99% without the need for any other chiral auxillary.     

Site-directed spin labeling electron paramagnetic resonance study of the calcium-induced structural transition in the N-domain of human cardiac troponin C complexed with troponin I

Calcium-induced structural transition in the amino-terminal domain of troponin C (TnC) triggers skeletal and cardiac muscle contraction. The salient feature of this structural transition is the movement of the B and C helices, which is termed the "opening" of the N-domain. This movement exposes a hydrophobic region, allowing interaction with the regulatory domain of troponin I (TnI) as can be seen in the crystal structure of the troponin ternary complex [Takeda, S., Yamashita, A., Maeda, K., and Maeda, Y. (2003) Nature 424, 35-41]. In contrast to skeletal TnC, Ca(2+)-binding site I (an EF-hand motif that consists of an A helix-loop-B helix motif) is inactive in cardiac TnC. The question arising from comparisons with skeletal TnC is how both helices move according to Ca(2+) binding or interact with TnI in cardiac TnC. In this study, we examined the Ca(2+)-induced movement of the B and C helices relative to the D helix in a cardiac TnC monomer state and TnC-TnI binary complex by means of site-directed spin labeling electron paramagnetic resonance (EPR). Doubly spin-labeled TnC mutants were prepared, and the spin-spin distances were estimated by analyzing dipolar interactions with the Fourier deconvolution method. An interspin distance of 18.4 A was estimated for mutants spin labeled at G42C on the B helix and C84 on the D helix in a Mg(2+)-saturated monomer state. The interspin distance between Q58C on the C helix and C84 on the D helix was estimated to be 18.3 A under the same conditions. Distance changes were observed by the addition of Ca(2+) ions and the formation of a complex with TnI. Our data indicated that the C helix moved away from the D helix in a distinct Ca(2+)-dependent manner, while the B helix did not. A movement of the B helix by interaction with TnI was observed. Both Ca(2+) and TnI were also shown to be essential for the full opening of the N-domain in cardiac TnC.     

Adult Mortality Attributable to Preventable Risk Factors for Non-Communicable Diseases and Injuries in Japan: A Comparative Risk Assessment

Background

The population of Japan has achieved the longest life expectancy in the world. To further improve population health, consistent and comparative evidence on mortality attributable to preventable risk factors is necessary for setting priorities for health policies and programs. Although several past studies have quantified the impact of individual risk factors in Japan, to our knowledge no study has assessed and compared the effects of multiple modifiable risk factors for non-communicable diseases and injuries using a standard framework. We estimated the effects of 16 risk factors on cause-specific deaths and life expectancy in Japan.

Methods and Findings

We obtained data on risk factor exposures from the National Health and Nutrition Survey and epidemiological studies, data on the number of cause-specific deaths from vital records adjusted for ill-defined codes, and data on relative risks from epidemiological studies and meta-analyses. We applied a comparative risk assessment framework to estimate effects of excess risks on deaths and life expectancy at age 40 y. In 2007, tobacco smoking and high blood pressure accounted for 129,000 deaths (95% CI: 115,000–154,000) and 104,000 deaths (95% CI: 86,000–119,000), respectively, followed by physical inactivity (52,000 deaths, 95% CI: 47,000–58,000), high blood glucose (34,000 deaths, 95% CI: 26,000–43,000), high dietary salt intake (34,000 deaths, 95% CI: 27,000–39,000), and alcohol use (31,000 deaths, 95% CI: 28,000–35,000). In recent decades, cancer mortality attributable to tobacco smoking has increased in the elderly, while stroke mortality attributable to high blood pressure has declined. Life expectancy at age 40 y in 2007 would have been extended by 1.4 y for both sexes (men, 95% CI: 1.3–1.6; women, 95% CI: 1.2–1.7) if exposures to multiple cardiovascular risk factors had been reduced to their optimal levels as determined by a theoretical-minimum-risk exposure distribution.

Conclusions

Tobacco smoking and high blood pressure are the two major risk factors for adult mortality from non-communicable diseases and injuries in Japan. There is a large potential population health gain if multiple risk factors are jointly controlled. Please see later in the article for the Editors'' Summary     

Cancer Mortality Studies in Misara,a Radon Hot Spring in Japan: A Summary up to 2003

Misasa, which is well known for its radon hot springs, is a historical town located in Tottori Prefecture, Japan. The presence of the hot springs is noted in an 1164 entry in town records. The presence of radioactivity in the hot springs was recognized in 1914. Since ancient times, the spring water has been believed to be healthful. The town of Misasa has 90 radon hot spring sources, yielding a total volume of 3,000 tons of spring water a day. The concentration of ²²²Rn in the spring water ranges from 17.4 to 9,361 Bq per liter. A series of cancer mortality studies on the radon hot springs were conducted through the collaboration of scientists scattered throughout different Japanese cities. At present, no definite evidence has been discovered that indicates an increase of cancer mortality in the Misasa radon hot spring area. Even a lower risk was found for stomach cancers in both radon and no-radon hot springs.     

Early-stage vegetation recovery in forests damaged by oak wilt disease and deer browsing: effects of deer-proof fencing and clear-cutting

Landscape and Ecological Engineering - Oak wilt disease and deer browsing have depleted the canopy and forest floor of secondary Quercus serrata and Quercus variabilis forests in Japan. Small-scale...     

Synthesis of zinc bacteriochlorophyll-d analogues with various 17-substituents and their chlorosomal self-aggregates in non-polar organic solvents

Zinc 3(1)-demethyl-bacteriopheophorbides-d possessing various 17-propionate residue (17(2)-COOCH2-) were prepared as models of light-harvesting pigments in major photosynthetic antennae of green bacteria. The synthetic compounds were monomeric in polar organic solvents to give the same visible absorption spectra, but self-aggregated in non-polar organic solvents to afford large oligomers with broadened and red-shifted absorption bands. The peak positions were identical for all the self-aggregates but the widths of the redmost (Qy) bands were dependent upon the substituents. More hydrophobic and less sterically hindered hydrocarbon moieties as the esterifying group sharpened oligomeric Qy bands, giving less inhomogeneous supramolecular structures due to stabilization of the self-aggregates. In the reverse esters (17(2)-CH2OCO-) structurally isomeric to the above compounds, the same optical behavior was observed. Movement of the oxo group from the 17(3)- to 17(5)-position (17(2)-COOCH2--->17(2)-CH2OCO-) slightly increased the widths of self-aggregated Qy bands without change of the peak positions, where minor less self-aggregated components would enhance in the solution due to a little more stabilization of such species by the 17(4)-carbonyl group.     

Induction of Cytoplasmic Streaming and Movement of Chloroplast Induced by L-Histidine and its Derivatives in Leaves of Egeria densa

Rotational cytoplasmic streaming in leaves of Egeria densa wasinduced by light as well as by L-histidine (L-His). During bothtreatement with light and with L-His chloroplasts on the periclinalface were dislodged and moved to the anticlinal face where rotationalcytoplasmic streaming occurred. The effective concentrationof L-His was about 0.01 mM and the effect was almost saturatedat 0.1 mM. A derivative of L-His, 3-methyl-L-histidine, wasslightly less effective than L-His. By contrast, 1-methyl-L-histidinewas almost ineffective for induction of streaming, not onlyin Egeria but also in Vallisneria. Our resutlts are in markedcontrast to Fitting's result (1936) that 1-M-L-His is more effectivethan L-His. In Egeria, 1-methyl-L-His counteracted the stimulativeeffect of L-His. 1-Methyl-L-His penetrated into leaf cells ofEgeria to the same extent as 3-methyl-L-His and to a greaterextent than L-His. This observation excludes the possibilitythat the impermeability of leaves to 1-M-L-His might be responsiblefor its ineffectiveness. 1-M-L-His did not interfere with photodinesis.Differences in the mechanism of induction of rotational streamingby L-His and by light are discussed. ⁴ Present address: Fukui Institute of Technology, Gakuen, Fukui,910 Japan (Received July 16, 1990; Accepted December 20, 1990)