Formation of a Tree having a Low Lignin Content

Received 30 September 2001/ Accepted in revised form 26 October 2001     

Mutual interactions between optic lobe circadian pacemakers in the cricket Gryllus bimaculatus

The coupling mechanism between the bilaterally paired optic lobe circadian pacemakers in the cricket Gryllus bimaculatus was investigated by recording locomotor activity, under constant light or constant red light, after the optic nerve was unilaterally severed.

Continuous culture with deep seawater of a benthic food diatom Nitzschia sp.

A continuous culture system for a benthic food diatom Nitzschia sp. wasestablished by using properties of high nutrient and clean of deep seawater(DSW). DSW collected from 320 m depth in Muroto City, Japan, was introducedinto a glass-pipe bioreactor (14 cm length, 3 cm diam.) containing glassbeads of 0.5 cm diam. as substrata for the alga, and it was incubated at18°C · 80Em^–2sec^–1 · L:D=14:10. The chlorophyll a yield of benthicdiatoms in a reactor as a unit of surface area of the substratum was only0.001–0.003 g cm^–2 when the flow rate of DSW was 0(batch culture conditions). However, when DSW was supplied continuously to areactor, the yield increased to 1.4 g-chl.a cm^–2 alongwith the increase in flow rate of DSW. Moreover, amounts of chl.a washed outof the system were negligible, 0.0014 to 0.0045%, even though theflow rate of DSW was as much as 25 times h^–1, suggesting thatsloughing of benthic diatoms from the substratum was minimized. Although theyield of diatoms fluctuated significantly at the time that the DSW wascollected, the variation could be minimized by increasing the flow rate ofDSW. These results indicate that the continuous culturing system with DSWsupports the stable and effective mass culture of benthic food diatom.     

Formation of bioorganic compounds in aqueous solution induced by flames

Flames of flammable gases, when blown against a surface of an aqueous solution of organic compounds, were found to induce oxidation as well as other reactions in the solution. This reaction would be regarded as a new model for formation of bioorganic molecules in the primitive hydrosphere exposed to some radical-containing atmosphere.     

Break points in Arrhenius plots of the Hill reaction of spinach chloroplast fragments in the temperature range from -25 to 25?C

The relationship between temperature and 2,6-dichlorophenolindophenol(DPIP) photoreduction activity in chloroplast fragments isolatedfrom spinach grown at different temperatures was investigatedin the temperature range from –25 to 25?C. Two break points in the slope of the Arrhenius plot of the Hillreaction were observed at –9 and 11?C in chloroplast fragmentsisolated from spinach grown at low temperatures (0–10?C).These breaks were not affected by an uncoupler. In chloroplastfragments from spinach grown in a higher temperature range (10–30?C),only one break point was observed at –9?C. The other breakpoint at around 10?C appeared after treatment with detergent.Both break points were completely abolished by fixing the chloroplastfragments with glutaraldehyde. The break at around 10?C in chloroplast fragments isolated fromspinach grown at lower temperature was interpreted as due toacclimation rather than chilling sensitivity. (Received September 6, 1977; )     

A new shuttle vector forBacillus stearothermophilus andEscherichia coli

Summary A new shuttle vector was constructed by inserting a 3.1 kbp-DNA fragment from thermophilicBacillus sp. plasmid pIH41 intoEscherichia coli plasmid pUC18. The resultant hybrid replicates in bothE. coli andB. stearothermophilus. This vector has ten unique restriction sites within a part oflacZ gene. Insertion of foreign DNA into these sites can be readily detected by a coloration method.     

Growth of the hydrocarbon-rich microalga Botryococcus braunii in secondarily treated sewage

Summary A hydrocarbon-rich green microalga, Botryococcus braunii, was able to grow well in secondarily treated sewage (STS) from domestic waste-water in a batch system. The growth in STS from domestic waste-water was as good as in the common artificial medium of modified Chu 13 and its hydrocarbon contents were high enough at 53% and 40% compared with 58% in the case of the modified Chu 13 medium. B. braunii utilized nitrate from 7.67 or 4.48 mg/l to a level below detection of < 0.01 mg/l in STS. After this consumption of nitrate, nitrite was consumed, and ammonium was not. Phosphate, even at an extremely low concentration, was also consumed by B. braunii. These results show the possibility of using STS as a medium to grow B. braunii and for removal of nitrogen and phosphorus by algal consumption in STS.Correspondence to: S. Yokoyama     

Ultraviolet imaging densitometry of unstained gels for two-dimensional electrophoresis

A system suitable for ultraviolet imaging densitometry of two-dimensional electrophoretic gels that are unstained is described, together with its applications. A flying-spot densitometer linked with a personal computer was used for data acquisition, generation of mapping data, and image processing. Randomly distributed zones of proteins on two-dimensional gels were detected at 280 nm without being stained by two-dimensional scanning, and the densitometric value of each pixel (0.2 x 0.2 mm) was memorized by the computer, which generated a mapping pattern with density contours. The amount and densitometric value of cytochrome c had a linear relationship in the range of 2-200 micrograms. Zone locations of bovine liver proteins separated on two-dimensional gels were indicated on a map expressed in X-Y coordinates, and the pIs and molecular weights could be calculated from the map by use of pI and molecular weight markers on the same gel.     

HLA antigens in Japanese populations.

HLA antigens in 841 healthy, unrelated Japanese from nine widely separated geographic localities were studied. The five most common antigens observed in order of decreasing frequency were for the HLA-A locus: HLA-A9, A2, A10, AW32 and A11; and for the HLA-B locus: HLA-'B5' (= HLA-B5+B17), BW40, B12, B14 and B8. The allelic frequency of undetected antigens of the HLA-A locus was .14-.37, and that of the HLA-B locus, .32-.67, indicating that there were serological difficulties in typing for Japanese antigens using antisera from Caucasians. Marked gene frequency clines were observed for HLA-A9 and HLA-A2 from south (Okinawa) to north (Nagoya). Two haplotypes, HLA-A9, B5 and HLA-A10, BW40 were shown to be in linkage disequilibrium in four of the nine subpopulations.     

Microtubular origin of mitotic spindle form birefringence. Demonstration of the applicability of Wiener''s equation

Meiosis I metaphase spindles were isolated from oocytes of the sea-star Pisaster ochraceus by a method that produced no detectable net loss in spindle birefringence. Some of the spindles were fixed immediately and embedded and sectioned for electron microscopy. Others were laminated between gelatine pellicles in a perfusion chamber, then fixed and sequentially and reversibly imbibed with a series of media of increasing refractive indices. Electron microscopy showed little else besides microtubules in the isolates, and no other component present could account for the observed form birefringence. An Ambronn plot of the birefringent retardation measured during imbibition was a good least squares fit to a computer generated theoretical curve based on the Bragg-Pippard rederivation of the Wiener curve for form birefringence. The data were best fit by the curve for rodlet index (n1) = 1.512, rodlet volume fraction (f) = 0.0206, and coefficient of intrinsic birefringence = 4.7 X 10(-5). The value obtained for n1 is unequivocal and is virtually as good as the refractometer determinations of imbibing medium index on which it is based. The optically interactive volume of the microtubule subunit, calculated from our electron microscope determination of spindle microtubule distribution (106/mum2), 13 protofilaments per microtubules, an 8 nm repeat distance and our best value for f, is compatible with known subunit dimensions as determined by other means. We also report curves fitted to the results of Ambronn imbibition of Bouin's-fixed Lytechinus spindles and to the Noll and Weber muscle imbibition data.