Immunoblotting of mite aeroallergens collected with an indoor Burkard air sampler

We examined the kinetics of airborne levels of mite allergen particles in a house by combined use of an indoor Burkard air sampler and immunoblotting. Airborne mite allergens collected on the Burkard sampling tape were transferred onto a nitrocellulose membrane, reacted with mouse monoclonal anti-mite allergen (Der pI) antibody, then treated with alkaline phosphatase conjugated anti-mouse IgG. Finally, the blotted allergen on the membrane was reacted with BCIP/NBT phosphatase, and purple spots visible by the naked eye were produced. The shape of the spots was observed under a microscope, and the spot area was measured by an image processor. This technique might be useful for analyzing the behavior of airborne allergen particles in indoor environments.     

Analysis of the NH2-Terminal 83rd Amino Acid of Escherichia coli GyrA in Quinolone-Resistance

Artificial mutations of Gyrase A protein (GyrA) in Escherichia coli by site-directed mutagenesis were generated to analyze quinolone-resistant mechanisms. By genetic analysis of gyrA genes in a gyrA temperature sensitive (Ts) background, exchange of Ser at the NH₂-terminal 83rd position of GyrA to Trp, Leu, Phe, Tyr, Ala, Val, and Ile caused bacterial resistance to the quinolones, while exchange to Gly, Asn, Lys, Arg and Asp did not confer resistance. These results indicate that it is the most important for the 83rd amino acid residue to be hydrophobic in expressing the phenotype of resistance to the quinolones. These findings also suggest that the hydroxyl group of Ser would not play a major role in the quinolone-gyrase interaction and Ser83 would not interact directly with other amino acid residues.     

Hydrocarbon composition of newly isolated strains of the green microalga Botryococcus braunii

Four new strains of Botryococcus braunii were isolated from Japanese waters and cultured under defined conditions. Their hydrocarbon content and composition were analyzed and compared with those of the Darwin and Berkeley strains. The Yamanaka strain produced only alkadienes characteristic of the A race, whereas the others, the Yayoi, Kawaguchi-1 and -2 strains as well as the Darwin and Berkeley strains, produced botryococcenes peculiar to the B race. The hydrocarbon content of the Yamanaka strain was 16.1 % dry weight and that of the B race strains ranged from 9.7 to 37.9%. Botryococcene composition of the Japanese strains differed from each other as well as from the Darwin and Berkeley strains. More than 50% of the hydrocarbons in the Yayoi, Darwin, and Berkeley strains were composed of C₃₄H₅₈, but the main components were different from one another as isomers. The Kawaguchi-1 and -2 strains did not have a high level of C₃₄ botryococcenes, C₃₂ ones being the main components. In these strains significant amounts of squalene-related compounds were detected.     

Novel preparation method for surfactant-coated enzymes using W/O emulsion

Summary A novel preparation method for surfactant-coated enzymes has been developed using a W/O emulsion. The enzymatic activity of chymotrypsin in isooctane significantly increased with the coating of surfactants. The surfactant-coated chymotrypsin showed a high enzymatic activity for amidation, although powdered chymotrypsin did not show the activity. Further, the coated enzyme showed a remarkably high storage stability.     

Auxin-Induced Changes in the Molecular Weight Distribution of Cell Wall Xyloglucans in Avena Coleoptiles

The effect of auxin on the molecular weight (Mw) distributionof cell wall xyloglucans was investigated by gel permeationchromatography using coleoptile segments of Avena sativa L.cv. Victory, and the following results were obtained.

1. The water-insoluble hemicellulose (HC-A) mainly consisted ofxyloglucans. Iodine staining method revealed that relativelylarge amounts of xyloglucans were present in the water-solublehemicellulose (HC-B) and water-soluble polysaccharide (WS) fractions.
2. IAA did not cause remarkable changes in xyloglucan contentsin the hemicellulose, but significantly increased the xyloglucancontent in the WS fraction.
3. IAA substantially decreased theweight-average Mw of HC-A. Thiseffect became apparent within30 min of the incubation period,and was not affected by the0.15 M mannitol or 2% sucrose applied.Hydrogen ions also causeda decrease in the weight-average Mwof HC-A; its effect beingreversible.
4. Neither IAA nor hydrogen ions caused any remarkablechangesin the weightaverage Mw of water-soluble xyloglucansin theHC-B.

These results suggest that cell wall xyloglucans have an importantrole in auxininduced cell wall loosening in oat coleoptile cells. (Received May 10, 1984; Accepted August 20, 1984)     

Growth Regulation of Dark-grown Dwarf Barley Coleoptile by the Endogenous IAA Content

Growth curves of dark-grown coleoptiles of 11 isogenic coleoptilardwarf strains of barley (Hordeum vulagare L. cv. Akashinriki:uzu, 5, 77, 97, 105, 125, 131, 133, 136, 145 and 148) were simulatedwith a logistic equation and the endogenous IAA contents ofthe barley strains were determined. Growth analysis of the dwarfbarley coleoptiles revealed that the final coleoptile lengthwas correlated with the growth rate on the 2nd day after germination(r=0.897), when the growth rate was about maximum. The endogenousIAA Content of the barley strains, measured fluorometrically,indicated that on the 2nd day, the dwarf strains contained lessendogenous IAA than the normal Strain. The IAA content on the2nd day was correlated to the growth rate on the 2nd day (r=0.907,except for Strain 145) and the final coleoptile length (r=0.933,except for strains 77 and 145). The correlation, however, wasnot significant on the 3rd day. These results suggested thatthe dwarfism of the dark-grown coleoptiles of the barley Strainsexamined is primarily controlled by the endogenous IAA content. ¹ Present address: Department of Biology, Faculty of Science,Osaka City University, Osaka 558, Japan. (Received February 1, 1982; Accepted April 13, 1982)     

Effects of α-tocopherol analogs on lysosome membranes and fatty acid monolayers

The surface pressures of α-tocopherol analogs, fatty acids, and their mixtures were measured in their spread monolayers at an air—water interface. The surface pressure—area isotherms for the mixed monolayers of α-tocopherol and either stearic acid, oleic acid or linoleic acid deviated positively from those calculated on the basis of the additivity rule, and the magnitude depended on the length of the phytyl side chain in α-tocopherol and on the degree of unsaturation of the fatty acid chains. Lysosome membranes of mouse liver were stabilized by addition of α-tocopherol. A decrease in the length of the phytyl side chain in α-tocopherol reduced its ability to stabilize lysosome membranes. A good correlation was obtained between the extent of stabilizing activity of α-tocopherol analogs on lysosome membranes and the degree of positive deviation of the surface pressure for their mixtures with fatty acids.