Immunological characterization of a 36 kDa Fe deficiency specific peptide in barley roots

In a previous paper we reported that an acidic 36 kDa peptide is the most strongly induced peptide among several peptides induced by Fe deficiency in barley roots. In this paper, polyclonal antibodies were raised against the 36 kDa peptide. This peptide appeared in the roots of all the graminaceous species tested (barley, rye, wheat, oat, maize, sorghum and rice) in response to Fe deficiency. More of the peptide was found in the roots of graminaceous species which secrete higher amounts of mugineic acids (MAs) under Fe deficient nutrition status. Induction of the 36 kDa peptide was first observed on the third day of Fe deficiency, rising to a maximum value on the seventh day. The trend has a positive correlation with secretion of MAs during Fe deficiency. Further, resupply of Fe resulted in a decrease in peptide production on the second day, reaching a control level on the seventh day. The rate of decrease in peptide production was observed to be slower than that of MA secretion. Other nutrient stresses such as B excess, B deficiency, Cu excess, Cu deficiency, Mn excess, Mn deficiency, Zn excess and Zn deficiency induced far less of the peptide. The specific expression of the 36 kDa peptide in roots of graminaceous species under Fe deficiency suggested the positive association of the peptide with a specific Fe deficiency tolerance mechanism in graminaceous plants.     

Some properties of β-1,3-glucan hydrolyzing enzymes from the rotifer Brachionus plicatilis

We examined some characteristics of hydrolyticenzymes, especially -1,3-glucanase, to obtain theinformation of cell wall lytic enzymes forrotifers.Crude enzyme (ammonium sulfate fraction) of rotifershydrolyzed starch, -1,3-glucan, glycol chitinand CM-cellulose. Optimum pH for hydrolysis ofstarch and CM-cellulose was 6.5, and that for -1,3glucan and glycol chitin was pH 6.0. Pectic acid,xylan and agarose were not hydrolyzed at pH 3–10.-1,3 glucanase was purified about 73-fold from crudeenzyme by ion-exchange chromatography and gelfiltration. Optimum pH and temperature of the enzymewere 6 and 60 °C, respectively. The molecular weight ofthe enzyme was estimated about 260 kDa by gelfiltration. The enzyme was inhibited byHgCl₂ and MnCl_{_2}.     

Isolation of Cytopathic Small Round Virus (Aichi Virus) from Pakistani Children and Japanese Travelers from Southeast Asia

Aichi virus was isolated in Vero cells from 5 (2.3%) of 222 Pakistani children with gastroenteritis but none was found in 91 healthy children. Aichi virus was also isolated from 5 (0.7%) of 722 Japanese travelers returned from tours to Southeast Asian countries and complained of gastrointestinal symptoms at the quarantine station of Nagoya International Airport in Japan. Of 5 Japanese travelers, 3 were returning from Indonesia, and 2 from Thailand or Malaysia. These results indicate that Aichi virus or a similar agent is endemic in Southeast Asian countries and is a cause of gastrointestinal symptoms in children in these areas or in Japanese travelers who visit there.     

Regeneration of whole plants from protoplasts isolated from tissue-cultured shoot primordia of garlic (Allium sativum L.)

Protoplasts derived from tissue-cultured shoot primordia of garlic (Allium sativum L.) initiated successive cell divisions within 4 days and formed small individual calli (0.2mm in diameter) after 5 weeks of culture on Gamborg's B5 medium supplemented with 0.1% casein hydrolysate, 1mg/1 1-naphthaleneacetic acid and 1mg/1 6-benzylaminopurine. Plating efficiency was roughly 5% at the density of 1x10⁴ protoplasts/ml of medium. Adventitious buds developed from the calli during subsequent subculture on Gamborg's B5 medium supplemented with 40mg/l adenine and 10% coconut milk. When transferred to the same medium without supplements, these buds grew into shoots and rooted. The regenerated garlic plantlets were successfully transferred to the greenhouse and grew into whole plants.     

Expression of neural cell adhesion molecule (N-CAM) in perisinusoidal stellate cells of the human liver

Neural cell adhesion molecule (N-CAM) is distributed in most nerve cells and some non-neural tissues. The present immunohistochemical study has revealed, for the first time, the expression of N-CAM in perisinusoidal stellate cells of the human liver. Liver specimens were stained with monoclonal antibody against human Leu19 (N-CAM) by a streptoavidin-biotin-peroxidase-complex method. Light- and electron-microscopic analyses have shown that N-CAM-positive nerve fibers are distributed in the periportal and intermediate zones of the liver lobule. Perisinusoidal stellate cells in these zones are also positive for N-CAM. N-CAM is expressed on the surface of the cell, including cytoplasmic projections. Close contact of N-CAM-positive nerve endings with N-CAM-positive stellate cells has been observed. On the other hand, stellate cells in the centrilobular zone exhibit weak or no reaction for N-CAM. Perivascular smooth muscle cells and fibroblasts in the portal area and myofibroblasts around the central veins are negative for N-CAM. The present results indicate that the perisinusoidal stellate cells in the periportal and intermediate zones of the liver lobule characteristically express N-CAM, unlike other related mesenchymal cells, and suggest that the intralobular heterogeneity of N-CAM expression by stellate cells is related to the different maturational stages of these cells.     

Immunochemical characterisation and epitope mapping of a novel fimbrial protein (Pg-II fimbria) of Porphyromonas gingivalis

Abstract Mouse monoclonal antibody (mAb) Pgf-II specific for a 72-kDa major cell-surface protein (72K-CSP) derived from Porphyromonas gingivalis OMZ 409 was prepared. Immunoblotting analysis revealed that mAb Pgf-II reacted with 72K-CSP but not with 41-kDa fimbrial subunit protein (41K-fimbrilin) derived from P. gingivalis 381. Electron microscopic observation revealed that P. gingivalis OMZ 409 possessed peritrichous, thin fimbriae on their surface. Immunogold electron microscopy also demonstrated that mAb Pgf-II bound to the 72K-CSP examined with the gold particles arranged along the fibril array originating from the cell surface of the bacteria. These findings suggested that P. gingivalis 72K-CSP was identifiable as another fimbriae (termed Pg-II fimbriae) different from the fimbriae (termed Pg-I fimbriae) composed of a 41K-fimbrilin. Using multipin peptide synthesis technology, 102 sequential overlapping peptides covering the entire 514 amino-acid stretch of Pg-II fimbriae were synthesised. Seven immunodominant regions within Pg-II fimbrial protein molecule, which definitely reacted with the serum of patients with periodontal diseases, were detected.     

Oxidation of anionic nitroalkanes by flavoenzymes,and participation of superoxide anion in the catalysis

The reactivities of anionic nitroalkanes with 2-nitropropane dioxygenase of Hansenula mrakii, glucose oxidase of Aspergillus niger, and mammalian d-amino acid oxidase have been compared kinetically. 2-Nitropropane dioxygenase is 1200 and 4800 times more active with anionic 2-nitropropane than d-amino acid oxidase and glucose oxidase, respectively. The apparent K_m values for anionic 2-nitropropane are as follows: 2-nitropropane dioxygenase, 1.61 mm; glucose oxidase, 16.7 mm; and d-amino acid oxidase, 11.1 mm. Anionic 2-nitropropane undergoes an oxygenase reaction with 2-nitropropane dioxygenase and glucose oxidase, and an oxidase reaction with d-amino acid oxidase. In contrast, anionic nitroethane is oxidized through an oxygenase reaction by 2-nitropropane dioxygenase, and through an oxidase reaction by glucose oxidase. All nitroalkane oxidations by these three flavoenzymes are inhibited by Cu and Zn-superoxide dismutase of bovine blood, Mn-superoxide dismutases of bacilli, Fe-superoxide dismutase of Serratia marcescens, and other $\text{O}{}_2{}^{\mathrm{?}}$ scavengers such as cytochrome c and NADH, but are not affected by hydroxyl radical scavengers such as mannitol. None of the $\text{O}{}_2{}^{\mathrm{?}}$ scavengers tested affected the inherent substrate oxidation by glucose oxidase and d-amino acid oxidase. Furthermore, the generation of $\text{O}{}_2{}^{\mathrm{?}}$ in the oxidation of anionic 2-nitropropane by 2-nitropropane dioxygenase was revealed by ESR spectroscoy. The ESR spectrum of anionic 2-nitropropane plus 2-nitropropane dioxygenase shows signals at g₁ = 2.007 and g₁₁ = 2.051, which are characteristic of $\text{O}{}_2{}^{\mathrm{?}}$. The $\text{O}{}_2{}^{\mathrm{?}}$ generated is a catalytically essential intermediate in the oxidation of anionic nitroalkanes by the enzymes.     

Measurement of Stomatal Aperture by Digital Image Processing

We developed a new digital image processing technique for exactlymeasuring the degree of stomatal opening, that is, the ratioof the width to the maximum length of a stomatal pore, and thepore area. We applied this technique to evaluate responses toSO₂ of neighboring stomata in a small region of an intact attachedleaf, with the following results:

1. The pore region could be exactly extracted even when the originaldigital image was of poor quality. The standard errors in theevaluation of the pore area, the pore length, and the pore widthwere 10 µm², 0.3 µm and 0.3 µm, respectively.
2. A wide variety of responses to SO₂ was found among neighboringstomata in a small region of an attached leaf. The differenceswere especially remarkable before water-soaking and wilting.When these began, k₁ showed a local maximum value, and thenall the stomata began to close. These results suggest that stomatalresponses of intact growing plants to air pollutants shouldbe examined from the standpoint of not only the average movementof many stomata but also the movement of each stoma and thatthe interrelationship among movements of neighboring stomatashould be investigated to clarify the mechanism of stomatalresponses to air pollutants.

(Received June 4, 1984; Accepted August 23, 1984)     

Studies on antiviral glycosides. II. Mode of action for virucidal effects on Sendai virus

Treatment of Sendai virus with $\text{p-(sec-}\text{butyl)-phenyl-6-chloro-6-deoxy-β-}\text{d}\text{-glucopyranoside}$, followed by freezing and thawing resulted in a loss of hemolytic and cell fusion activities as well as infectivity without affecting hemagglutinating and neuraminidase activities. The anti-hemolytic activity of this compound was reversed by the addition of phosphatidyl choline to the virus samples. $\text{p-}\text{Azidophenyl-6-chloro-6-deoxy-β-}\text{d}\text{-[}{}^3\text{H]glucopyranoside}$ was successfully used for photoaffinity labeling of a specific virion site, and we confirmed the affected site of the glucoside to be the lipid components in the viral envelopes.     

Ultrastructure of intracytoplasmic membranes of Methanomonas margaritae cells grown under different conditions

The development of intracytoplasmic membranes of Methanomonas margaritae cells grown under different culture conditions was studied. Growth on methane was strongly accelerated by the addition of copper ions. Acceleration by copper, however, was not observed in the case of growth on methanol. Cells grown on methane with copper possessed intracytoplasmic membranes along the cell periphery. When the organism was grown in a medium lacking copper, intracytoplasmic membranes appeared as large vesicles surrounded by a unit membrane at the periphery of the cell. The vesicles originated from paired membranes due to the absence of copper in the medium. Cells grown on methanol with or without copper possessed a number of vesicles of different sizes arranged in a chain along the cell periphery. The possible relationship between membrane arrangement and methane oxidation is discussed.