Linear and Conformation-Dependent Antigenic Sites on the Nucleoprotein of Rabies Virus

A set of 29 monoclonal antibodies (MAbs) specific for the rabies virus nucleoprotein (N protein) was prepared and used to analyze the topography of antigenic sites. At least four partially overlapping antigenic sites were delineated on the N protein of rabies virus by competitive binding assays. Indirect immunofluorescent antibody tests using MAbs with a series of rabies and rabies-related viruses showed that epitopes shared by various fixed and street strains of rabies virus were mainly localized at antigenic sites II and III, while epitopes representing the genus-specific antigen of Lyssavirus were widely presented at sites I, III and IV. All but one of seven MAbs specific for antigenic sites I, IV and bridge site (I and II) reacted with the antigen that had been denatured by sodium dodecyl sulfate or 2-mercaptoethanol, as well as with the denatured N protein in Western blotting assays. However, none of the MAbs against antigenic sites II and III reacted with the denatured antigen. These data indicate that antigenic sites I and IV, and sites II and III on the N protein of rabies virus are composed of linear and conformation-dependent epitopes, respectively.     

Movement of an Epithelial Layer Isolated from Early Embryos of the Newt, Cynops pyrrhogaster I. Development of Folding Movement of the Blastocoelic Wall Isolated from Embryos before and during Gastrulation

The blastocoelic wall (BW) was isolated from embryos of the newt, Cynops pyrrhogaster , before and during gastrulation. The mechanism responsible for the folding movement of the isolated BW toward the basal side was investigated. The BW isolated from the early gastrula was induced to fold toward the basal side by treatment with serum. The folding movement of the isolated BW took place from the late blastula to early gastrula stage. Electron microscopy, rhodamine-phalloidin staining and experiments with inhibitors show that the development of the folding movement was correlated with the appearance of a submembranous microfilaments layer (SML) which was formed beneath the cell membrane on the basal side of the BW and suggest that the contraction of actin filaments in the SML is involved in the folding movement of the isolated BW toward the basal side.     

Variance and covariances of the numbers of synonymous and nonsynonymous substitutions per site

Nei and Gojobori (1986) developed a simple method to estimate the numbers of synonymous (ds) and nonsynonymous (dN) substitutions per site. In the present paper, we have developed a method for computing variances and covariances of ds's and dN's and of the proportions of synonymous (ps) and nonsynonymous (pN) differences. We also have developed a method for computing the variances of mean dS, dN, pS, pN, without constructing a phylogenetic tree of the genes. We have conducted computer simulations based on simple evolutionary models and have shown that the new method gives good estimates of variances and covariances.      

Flash-induced photophosphorylation in chloroplasts with activated ATPase

Chloroplasts which were rapidly isolated from illuminated leaves showed activity of ATP hydrolysis at a level much higher than that of the dark control. Under the high-intensity illumination or under repetitive flash excitation, the activated chloroplasts synthesized more ATP than those with a low ATP hydrolysis activity. formed under repetitive flashes was smaller in the activated chloroplasts than in the inactive chloroplasts. The inhibition of ATP yield per flash by valinomycin or nigericin in the presence of K⁺ was stronger in the inactive chloroplasts than in the activated chloroplast. ATP synthesis in the activated chloroplasts seems to have a lower threshold.     

Inhibition of testicular androgenesis by urinary antigonadotropins and melatonin in rats.

Comparative in vitro and in vivo studies of the effects of urinary gonadotropin-inhibiting substances and melatonin on the androgenesis in rat testicular homogenates were performed. When the urinary extract containing the inhibiting substances or melatonin was added directly to the incubation medium, and was also injected into rats 24 and 48 hrs prior to sacrifice, either one was effective in suppressing the conversion of pregnenolone to testosterone and/or androstenedione in testicular tissues. The urinary extract exerted the inhibitory effect on the conversion of cholesterol to pregnenolone in vitro and in vivo, whereas melatonin did not have this effect in vitro and in vivo. These findings suggest that the antigonadotropic substances are different from melatonin in their action on androgenesis in the rat testes.     

Role of oxygen in auxin-induced ethylene production

Ethylene production by IAA-treated mung bean hypocotyl segmentsunder various oxygen levels in the ambient atmosphere was examined.Rate of ethylene production was dependent upon oxygen levels,and gave a sigmoidal curve against oxygen levels. Tissue segmentspreincubated with IAA in low oxygen levels (1–10% O₂ inN₂) produced ethylene without a lag period at a rate higherthan that by control tissue segments preincubated in air, whenthey were exposed to a high oxygen level (air, 21% O₂). Theeffect of cycloheximide on tissue segments transferred froma low oxygen level to air was not much different from that onethylene production by control tissue segments previously incubatedin air. Incorporation of U-¹⁴C-leucine into the protein fractionby tissue segments placed in nitrogen was negligible, but thatin 2% oxygen was 10 to 14% of that in air. It was concluded that oxygen was an essential factor for boththe induction process of the ethylene producing system and thesynthesis of ethylene, and that although synthesis of ethyleneis dependent upon oxygen levels, formation of the ethylene producingsystem proceeded even under low oxygen levels. (Received January 13, 1977; )     

Purification and properties of the polypeptide chain release factor (RF-4) from an extreme thermophile, Thermus thermophilus HB8.

The polypeptide chain release factor 1 (RF-1) has been purified from an extreme thermophile, Thermus thermophilus HB8. The purification procedure included steps of aqueous two-phase partition, ammonium sulfate fractionation, and column chromatographies on DEAE-Sephadex, Sephadex G-150, and CM-Sephadex. The preparation was more than 90% pure as judged by polyacrylamide gel electrophoresis. The specific activity was about 3.3 pmol of formyl-[3H]-methionine released in 1 min at 25 degrees C per microgram of protein under the standard assay conditions using 4 pmol of the initiation complex and 1 nmol of UpApG. The molecular weight as determined by gel filtration on Sephadex G-150 and by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, was 58,000 and 45,000, respectively. As expected, the factor was extremely heat-stable, 50% of its activity remaining after incubation for 5 min at 84 degrees C. Several properties of the reaction catalyzed by RF-1 are also described.     

Treatment of phenolic wastes byAureobasidium pullulans adhered to the fibrous supports

Summary Biological treatment of waste water containing a large amount of phenol was carried out by using a phenolassimilating fungus,Aureobasidium pullulans No. 14 adhered (semi-immobilized) to fibrous asbestos. The column reactor employed for oxidative degradation of phenol consisted of a cylindrical glass column containing plastic nets.During 27 days operation, it was observed that: 1) The phenol removal capacity of the reactor gradually increased during the first 10 days, reaching a stable level. 2) The best phenol removal capacity (50 mg phenol removed/h/ liter of reactor volume) was obtained when an artificial waste water containing up to 1,200 g/ml phenol was applied to the reactor. 3) Much higher concentrations of phenol (e.g. 1,700 g/ml) brought about a marked decrease in the phenol removal capacity (40–50 mg/h/liter). 4) Satisfactorily stable operation was achieved using the semiimmobilized mycelia ofAureobasidium pullulans, whose active state could be checked by observing the thick, black-colored biomass which is characteristic of the genusAureobasidium and covered the plastic nets inside the glass column reactor.