An oligonucleotide probe for the detection of Erwinia herbicola and Erwinia ananas

An oligonucleotide probe targeting the rRNA of Erwinia herbicola and Erwinia ananas was designed to detect their cells using fluorescence in situ hybridization. The Cy3-labeled probe hybridized strongly with these species but very weakly with nontarget species such as Erwinia mallotivora, Erwinia nigrifluens, Erwinia cypripedii, Erwinia chrysanthemi, Erwinia carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Escherichia coli. This technique visualized E. herbicola cells after inoculation of kumquat fruits. The probe is promising as a tool for studying population dynamics of E. herbicola and E. ananas.     

Effects of brief exposure of male pheromone on multiple-unit activity at close proximity to kisspeptin neurons in the goat arcuate nucleus

Exposure of females to the male pheromone induces pulsatile release of gonadotropin-releasing hormone (GnRH) in goats. Recently, kisspeptin neurons in the arcuate nucleus (ARC) have been suggested to represent the proximate source of the GnRH pulse generator. In this study, we examined the effects of the pheromone on multiple-unit activity (MUA) in female goats fitted with recording electrodes aimed at the ARC kisspeptin neurons. In all eight goats, periodic bursts in MUA (MUA volleys), which were considered to be electrophysiological manifestations of the GnRH pulse generator, were observed. The mean intervolley interval (T) during the control period was calculated in each goat that was then exposed to the male pheromone for 1 sec at timings of 1/4 T, 1/2 T or 3/4 T after one regularly occurring MUA volley. An instantaneous rise in MUA was observed immediately after the exposure regardless of timing. Exposure at a timing of 3/4 T resulted in an MUA volley within 60 sec following the instantaneous rise in all goats. In contrast, an MUA volley was induced in only 2 goats by exposure at 1/2 T, while exposure at 1/4 T failed to induce an MUA volley in any goats. These results suggest that transmission of the pheromone signal to the ARC, represented by an instantaneous rise, activates the GnRH pulse generator. Moreover, the timing-dependent pheromone action in inducing an MUA volley indicates that the GnRH pulse generator has a refractory period for the pheromone signal after the burst.     

Endemic infections of bovine viral diarrhea virus genotypes 1b and 2a isolated from cattle in Japan between 2014 and 2020

Bovine viral diarrhea virus (BVDV) is a causative agent of bovine viral diarrhea. In Japan, a previous study reported that subgenotype 1b viruses were predominant until 2014. Because there is little information regarding the recent epidemiological status of BVDV circulating in Japan, we performed genetic characterization of 909 BVDV isolates obtained between 2014 and 2020. We found that 657 and 252 isolates were classified as BVDV-1 and BVDV-2, respectively, and that they were further subdivided into 1a (35 isolates, 3.9%), 1b (588, 64.7%), 1c (34, 3.7%), and 2a (252, 27.7%). Phylogenetic analysis using entire E2 coding sequence revealed that a major domestic cluster in Japan among BVDV-1b and 2a viruses were unchanged from a previous study conducted from 2006 to 2014. These results provide updated information concerning the epidemic strain of BVDV in Japan, which would be helpful for appropriate vaccine selection.     

Characterization of collagen and its hydrolysate from yellowfin tuna Thunnus albacares skin and their potencies as antioxidant and antiglycation agents

Fisheries Science - Collagen is one of the biopolymer proteins that may be useful for food and non-food purposes. Recently, even for collagen, it is becoming necessary to meet the requirements of...     

Factors affecting the growth of in vitro cultured lateral buds from Phalaenopsis flower stalks

Phalaenopsis flower-stalk buds cultured in vitro show 3 modes of growth: dormant, vegetative and reproductive. The effects of bud position on the stalk, temperature, and benzyladenine (BA) on the mode of bud growth were examined.Flower stalks were cut into 1-node sections, each with 1 bud, and inserted into solid culture medium, top side up. Buds on the upper sections had a tendency to remain dormant regardless of temperature. Sprouting buds placed at 20°C or 25°C showed reproductive growth except for some on the basal sections which grew vegetatively. At 28°C, all buds developed vegetatively independent of their original position on the stalk. The buds on the sections taken from both stalks which had elongated at min 18°C and min 28°C were subcultured; the mode of growth of the cultured buds was not affected by the temperature during flower-stalk elongation but was affected by the subsequent culture temperature.Cultured buds which had remained dormant were stimulated to sprout by addition of BA to the medium. At 5 p.p.m. and above, all buds began to develop, but malformations developed on the leaves of the shoots. All factors considered, BA at 2.5 p.p.m. was found to be the optimum level. The further development of the buds released from dormancy by BA was also affected by the position on the flower stalk and by cultural temperature.     

Identification of introgression lines of Oryza glaberrima Steud. with high mineral content in grains

Mineral concentrations in cereals are crucial for human health, especially for people who consume cereals as a subsistence diet. Although rice (Oryza sativa L.) is one of most important staple crops in the world, starch constitutes a large portion of its grains, and mineral concentrations are lower than in other staple crops. One solution is the improvement of mineral concentrations in rice grains through biofortification, and this approach requires investigation of genetic resources that confer high mineral concentrations to rice grains. In the present study, we performed 2 years of field experiments, in 2012 and 2013, and determined sodium (Na), magnesium (Mg), phosphorus (P), potassium (K), calcium (Ca), boron (B), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn) and molybdenum (Mo) concentrations in the rice grains of 40 introgression lines derived from a cross between a japonica cultivar, Taichung 65 (T65), and African rice, Oryza glaberrima Steud. Substantial variation in mineral concentrations was observed among the 40 introgression lines. We selected several elite lines that had significantly higher concentrations of minerals, including Fe, Cu, Zn, Mo, Mg, P and Ca than the cultivated rice T65. These lines could be novel potential materials for breeding programs for biofortification and provide us with positional information for the candidate loci in the O. glaberrima genome responsible for high mineral concentrations in rice grains.     

Improvement of fiberboard made from acetylated fibers by ozonation I: effect of ozonation on mechanical properties

Acetylated fibers with a 24.8% weight gain by acetylation were ozonated with 0%–2.0% ozone on fibers. Fiberboards were then made from these treated fibers. The internal bond and bending strength of the acetylated fiberboards increased drastically with increasing ozone charge up to 0.5%–1.0%, whereas the thickness swelling of the fiberboards decreased. Ozone selectively cleaves the aromatic rings of hydrophobic lignin and introduces a hydrophilic carboxyl group into lignin. Thus, the wettability and thermoplasticity of acetylated fibers increased, and this structural modification improved the interfiber contact. Internal bond and bending strength increased as a result. In addition, steep density profiles were formed by the ozonation, resulting in high bending strength. The high compaction ratio accelerated the effect of ozonation. The optimum ozone charges for improving mechanical properties were 0.5%–1.0%.Part of this report was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999     

Growth, nitrogen fixation and mineral acquisition of Alnus sieboldiana after inoculation of Frankia together with Gigaspora margarita and Pseudomonas putida

The role of tetrapartite associations among Frankia, Gigaspora margarita (an arbuscular mycorrhizal fungus), Pseudomonas putida (rhizobacterium), and Alnus sieboldiana in growth, nitrogen fixation, and mineral acquisition of A. sieboldiana was investigated. Seedlings of A. sieboldiana were inoculated with Frankia isolated from root nodules of alder, followed by inoculation of G. margarita and P. putida, and were grown for 5 months in a greenhouse. The seedlings inoculated with Frankia and G. margarita together produced the highest biomass of shoots and root nodules. Nitrogen-fixation activity, measured by acetylene reduction assay, was observed when Frankia was inoculated. The activity, on a per-nodule gram basis, decreased after G. margarita inoculation, but on a per-plant basis there was no significant difference in the activity among inoculation treatments. The mineral content in the seedlings changed after inoculation with Frankia, but not after inoculation with P. putida and/or G. margarita. The results showed a synergistic interaction among Frankia, the mycorrhizal fungus, and the rhizobacterium on the growth of A. sieboldiana.     

Hybrid aspen with a transgene for fungal manganese peroxidase is a potential contributor to phytoremediation of the environment contaminated with bisphenol A

To assess the possible utility of a fungal gene for manganese-dependent peroxidase (MnP) produced by a transgenic plant in phytoremediation, we transformed hybrid aspen with a chimeric gene for MnP. Our gene construct allowed expression of the gene for MnP in plants and relatively high MnP activity was detected in the hydroponic medium in which roots of plants that expressed the transgene had been cultured. Some of our transgenic plants were able to remove bisphenol A from the medium more efficiently than wild-type plants. Our results demonstrate that, without any modification of the coding sequence, a chimeric gene for fungal MnP can be expressed in a woody plant, with secretion of active MnP from roots into the rhizosphere. Our strategy suggests new options using woody plants for phytoremediation.