Teruo Matsubara

Breakdown of mineral grains by earthworms and beetle larvae

Feeding experiments were conducted quantitatively to examine the breakdown of mineral grains by earthworm, Eisenia feida, and larva of beetle, Protaetia lugubris insperata. Crushed and sieved test minerals of K-feldspar and/or quartz were mixed with artificial humus that contained no mineral grains. The mixture was fed to the soil animals in the plastic containers. After 1-, 4- and 7-day experimental durations, the ingested mineral grains were collected from the casts excreted by the soil animals in each container. Even 1 day after feeding of mineral grains, the casts of soil animals contained finer, rounded mineral grains that were not included in the initial prepared mineral samples.

Copper as a controlling factor of anaerobic growth under N2O and biosynthesis of N2O reductase in denitrifying bacteria

In order to determine the specific mineral requirement for N2O-anaerobic growth of the denitrifying bacteria Alcaligenes sp. NGIB 11015 and Alcaligenes faecalis IAM 1015, investigations were done using dithizone-treated KNO3-free modified Giltays medium (dithizone-treated medium). When grown aerobically, the bacteria exhibited equally good growth in the presence or absence of an appropriate amount of copper. Anaerobic growth under N2O was stimulated by the addition of a proper amount of copper in both denitrifying bacteria. Growth in the medium demetalated by various treatments showed that copper was specifically necessary for the maximum growth under N2O. The optimum concentration of copper was between 0.5 to 1 μm and 20 to 40 μm for the anaerobic growth rate under N2O. Copper was indispensable for the biosynthesis of N2O reductase and is very likely to be a functional part of N2O reductase in denitrifying bacteria.

Fluctuation of nut production and seedling appearance of a Japanese beech (Fagus crenata Blume)

The nut productivity, density of fallen nuts, seedling appearance and seedling survival of a Japanese beech (Fagus crenata Blume) were investigated at three localities, Mt Gozaisho, Mt Hodaka and Mt Bandai, Japan, from 1976 to 1992. Two patterns of cycles, a short cycle and a long one, were confirmed in the beech nut productivity. Synchronization in the long cycle was recognized both on Mt Hodaka and Mt Bandai. On Mt Gozaisho, the beech nut productivity was quite low, and the seedlings disappeared within 1 year. The phenomenon on Mt Gozaisho seemed to be caused by the low matter production mainly due to erosion and poor soils. A large number of seedlings appeared in the next spring of heavy mast years on Mt Hodaka and Mt Bandai. The large beech nut productivity contributed to the large seedling supply, and this enhanced the survival probability of beech seedlings. This demonstrates the possibility that beech seedlings survived longer even under dense dwarf bamboos, particularly if the seedling supply was large.

Spectral properties of carbon monoxide or cyanide complexes of cytochromes c′ from denitrifying bacteria

Abstract The CO and CN − derivatives of cytochromes c ′ from three denitrifying bacteria ( Alcaligenes sp. NCIB 11015 and Achromobacter xylosoxidans GIFU 543 and 1051) have been investigated by electronic absorption and magnetic circular dichroism (MCD) spectroscopy at room temperature. The spectral data have been characterized and compared with those of the corresponding derivatives of cytochromes c ′ from photosynthetic bacteria, cytochrome c , and hemoproteins containing b-type heme such as myoglobin, horseradish peroxidase, and indoleamine 2,3-dioxygenase. The absorption and MCD spectra of the CO-cytochromes c ′ complexes from the above denitrifying bacteria show low-spin ferrous chromophores with extra weak bands at around 435 nm, which are assigned to the unreacted ferrous species (high-spin). The yields of the unreacted species are 6–18%. Complete formation of the CO complex of Alcaligenes cytochrome c ′ takes place in the presence of n-propanol (50% n-propanol/50% 0.05 M phosphate buffer, pH 7.2). Since cytochromes c ′ from most photosynthetic bacteria give the 100% CO complexes, their CO affinities seem to be generally higher than those of cytochromes c ′ from denitrifying bacteria. The binding of cyanide to Alcaligenes ferric cytochrome c ′ is spectroscopically demonstrated as the second CN − complex (low-spin) reported after the CN − -cytochrome c ′ complex from Chromatium vinosum (a photosynthetic bacterium) reported already, although anionic ligands were earlier reported not to bind to the ferric cytochromes c −. The treatment of the CN − complex with Na 2 S 2 O 4 results in formation of the ferrous CN − complex (low-spin) with a small amount of the free ferrous species (high-spin).

Occurrence of laccase and tyrosinase in fungi of agaricales and comparative study of laccase fromRussula delica andRussula pseudodelica

The activities of laccase and tyrosinase, that is, oxidation activities ofp-phenylenediamine andp-cresol in the fruiting bodies of species belonging to various genera of Agaricales were examined. Among 40 genera examined, appreciable laccase activities were observed in fungi belonging toLepista, Omphalina, Agaricus, Russula andLactarius. High typosinase activities were found in many species ofHygrophorus, Laccaria, Lepista, Melanoleuca, Collybia, Marasmius, Amanita, Agaricus, Inocybe, Pholiota, Russula andLactarius. Species of other genera exmained did not show either enzyme activities to any extent.FromRussula delica andRussula pseudodelica, laccases were extracted and purified, and some characteristics were compared. Molecular weight and absorption spectra of these laccases were very similar to each other, but they were different in electrophoretical mobilities and substrate specificity.

Structural change in the one-electron oxidation-reduction at the copper site in nitrite reductase. Evidence from EXAFS

Abstract The structural change of the nitrite reductase in the one-electron reduction at the copper center has been studied using the EXAFS technique. In the one electron reduction, the Cu(cystein) distance is elongated by about 0.1 A, and CuN(imidazole) distance are slightly changed.

Ecological studies on the plants of Fagaceae. V: Growth in the sapling stage and minimal participation of reserve materials in the formation of annual new shoots of the evergreen Quercus glauca Thunb.

The growth in the sapling stage and participation of reserve materials in the formation of annual new shoots were studied in the evergreen treeQuercus glauca. The growth and some allometric relationship were analyzed for 1-to 4-year-oldQ. glauca plants. Each individual was felled at the foot, or all the leaves were removed at the end of the growth season (December). Sprouts were formed on the remaining stump and new shoots were formed from winter buds under dark or light conditions. The dry weight of each plant part was measured before and afte,, the formation of these new shoots. The amount of reserve materials in each plant part was estimated from the difference in allometric relatationships before and after the formation of new shoots. Although the results showed that a small amount of reserve material existed in roots, the participation of reserve materials in the formation of annual new shoots was negligible inQ. glauca growing under usual conditions, and substrates for the formation of new shoots were derived from the products of photosynthesis in old leaves and developing new leaves. Some of the growth characteristics ofQ. glauca were compared with those of the deciduous speciesQuercus variabilis to explain ecological behavior of the two species in warmtemperate secondary forests.