Production of l-Phenylalanine from trans-Cinnamic Acid with Rhodotorula glutinis Containing l-Phenylalanine Ammonia-Lyase Activity

An enzymatic method using l-phenylalanine ammonia-lyase (EC 4.3.1.5) for the rapid conversion of trans-cinnamic acid to l-phenylalanine has been investigated. With Rhodotorula glutinis, enzyme activity as high as 0.3 U/ml of culture broth was obtained. The enzyme activity was kept stable for a relatively long time during cultivation by the addition of l-isoleucine. Optimization of the parameters of the conversion reaction resulted in accumulation of 18 mg of l-phenylalanine per ml of reaction mixture. The conversion yield from trans-cinnamic acid was about 70%. The method may provide a rapid and practical way to produce l-phenylalanine useful as an essential amino acid.     

Effect of midazolam and butorphanol premedication on inhalant isoflurane anesthesia in mice

Isoflurane is a representative inhalant anesthesia used in laboratory animals. However, isoflurane mediates respiratory depression and adverse clinical reactions during induction. In the present study, we established a novel balanced anesthesia method in mice that combined isoflurane anesthesia with midazolam and butorphanol (MB). Thirty-four male C57BL/6J mice received either isoflurane alone or isoflurane with an intra-peritoneal MB premedication (3 mg/kg midazolam and 4 mg/kg butorphanol). The minimum alveolar concentration (MAC) in each group was evaluated. Induction time and adverse clinical reactions were recorded in each group. Core body temperature, heart rate, respiratory rate, and oxygen saturation (SPO₂) were assessed before and for 1 h after induction. Premedication with MB achieved a significant reduction in MAC compared with isoflurane monoanesthesia (isoflurane, 1.38 ± 0.15%; isoflurane with MB, 0.78 ± 0.10%; P<0.05). Induction time was significantly shortened with MB premedication, and adverse reactions such as excitement or incontinence were observed less frequently. Furthermore, isoflurane anesthesia with MB premedication caused increase of respiratory rates compared to isoflurane monoanesthesia. No significant decrease of SPO₂ was observed in MBI anesthesia, while a decrease in SPO₂ was apparent with isoflurane monoanesthesia (baseline, 98.3% ± 1.1; 10 min after induction, 91.8 ± 6.4%; P<0.05). In conclusion, premedication with MB was effective for the mitigation of respiratory depression induced by isoflurane in mice, with rapid induction and fewer adverse clinical reactions.     

Plant clock modifications for adapting flowering time to local environments

During and after the domestication of crops from ancestral wild plants, humans selected cultivars that could change their flowering time in response to seasonal daylength. Continuous selection of this trait eventually allowed the introduction of crops into higher or lower latitudes and different climates from the original regions where domestication initiated. In the past two decades, numerous studies have found the causal genes or alleles that change flowering time and have assisted in adapting crop species such as barley (Hordeum vulgare), wheat (Triticum aestivum L.), rice (Oryza sativa L.), pea (Pisum sativum L.), maize (Zea mays spp. mays), and soybean (Glycine max (L.) Merr.) to new environments. This updated review summarizes the genes or alleles that contributed to crop adaptation in different climatic areas. Many of these genes are putative orthologs of Arabidopsis (Arabidopsis thaliana) core clock genes. We also discuss how knowledge of the clock’s molecular functioning can facilitate molecular breeding in the future.

Crop genes that have been implicated in the modulation of photoperiodic flowering time and adaptation include orthologs of Arabidopsis core clock genes.     

Intraspecific interference between native parasitoids modified by a non-native parasitoid and its consequence on population dynamics

1. The number of natural enemies that should be introduced to control a pest is a controversial subject in biocontrol. A previous semi-mechanistic model parameterised using a laboratory system consisting of two parasitoid wasps, Anisopteromalus calandrae and Heterospilus prosopidis, parasitising a pest beetle, Callosobruchus chinensis, indicated that the introduction of the non-native parasitoid H. prosopidis decreases the level of intraspecific interference between native A. calandrae females. The model also suggested that this decrease was the main factor destabilising the population dynamics of the host–parasitoid system, resulting in chaos. 2. To test this population-level decrease and host density independence in the interference of A. calandrae, we observed individual behaviours to quantify the level of intraspecific interference between two A. calandrae females in the presence or absence of H. prosopidis at two different host densities. 3. When H. prosopidis was present, the number of direct antagonistic interference events between A. calandrae females, sting duration, host feeding events (but not stinging events), and patch residence time were reduced. However, the presence of H. prosopidis decreased the patch residence time and the proportion of hosts parasitised by A. calandrae only when the host density was low. 4. The reduction in intraspecific interference between A. calandrae females by H. prosopidis and its host density independence support the population-level prediction, whereas the observed reduction in host-feeding behaviours in A. calandrae by H. prosopidis was not predicted. Overall pest control by the native parasitoid was unaffected by the non-native parasitoid as host density increased.     

An Assembly Intermediate Structure of Rice Dwarf Virus Reveals a Hierarchical Outer Capsid Shell Assembly Mechanism

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Vital signs monitoring during injectable and inhalant anesthesia in mice

Selecting the appropriate anesthetic protocol for the individual animal is an essential part of laboratory animal experimentation. The present study compared the characteristics of four anesthetic protocols in mice, focusing on the vital signs. Thirty-two male ddY mice were divided into four groups and administered anesthesia as follows: pentobarbital sodium monoanaesthesia; ketamine and xylazine combined (K/X); medetomidine, midazolam, and butorphanol combined (M/M/B); and isoflurane. In each group, rectal temperature, heart rate, respiratory rate, and O₂ saturation (SPO₂) were measured, and the changes over time and instability in these signs were compared. The anesthetic depth was also evaluated in each mouse, and the percentage of mice achieving surgical anesthesia was calculated. K/X anesthesia caused remarkable bradycardia, while the respiratory rate and SPO₂ were higher than with the others, suggesting a relatively strong cardiac influence and less respiratory depression. The M/M/B group showed a relatively lower heart rate and SPO₂, but these abnormalities were rapidly reversed by atipamezole administration. The pentobarbital group showed a lower SPO₂, and 62.5% of mice did not reach a surgical anesthetic depth. The isoflurane group showed a marked decrease in respiratory rate compared with the injectable anesthetic groups. However, it had the most stable SPO₂ among the groups, suggesting a higher tidal volume. The isoflurane group also showed the highest heart rate during anesthesia. In conclusion, the present study showed the cardiorespiratory characteristics of various anesthetic protocols, providing basic information for selecting an appropriate anesthetic for individual animals during experimentation.     

Transferrin receptor-1 suppresses neurite outgrowth in neuroblastoma Neuro2A cells

Transferrin receptor-1 (TfR1) is a cell membrane-associated glycoprotein responsible for incorporation of the iron bound to transferrin through an endocytotic process from the circulating blood. Iron is believed to play a dual role as an active center of the electron transfer system in mitochondria and as an endogenous cytotoxin through promoted generation of reactive oxygen species in different eukaryotic cells. In this study, we evaluated expression profiles of different genes related to iron mobilization across plasma membranes in neuronal cells. Marked mRNA expression was seen for various iron-related genes such as TfR1 in cultured mouse neocortical neurons, while TfR1 mRNA levels were more than doubled during culture from 3 to 6days. In mouse embryonal carcinoma P19 cells endowed to differentiate into neuronal and astroglial lineages, a transient increase was seen in both mRNA and corresponding protein for TfR1 in association with neuronal marker expression during culture with all-trans retinoic acid (ATRA). In neuronal Neuro2A cells cultured with ATRA, moreover, neurite was elongated together with increased expression of both mRNA and protein for TfR1. Overexpression of TfR1 significantly decreased the length of neurite elongated, however, while significant promotion was invariably seen in the neurite elongation in Neuro2A cells transfected with TfR1 siRNA as well as in Neuro2A cells cultured with an iron chelator. These results suggest that TfR1 would be highly expressed by neurons rather than astroglia to play a negative role in the neurite outgrowth after the incorporation of circulating transferrin in the brain.     

Distribution of dorsal carriage among simians

We surveyed the literature and obtained information from primate researchers and zookeepers to study the distribution of dorsal carriage among 77 simian species including New and Old World monkeys and apes in relation to arboreality and terrestriality, birth (litter) weight relative to maternal weight, and presence or absence of distinct natal coat colors. All New World monkeys are arboreal and commonly carry their infants dorsally. Conversely, arboreal Old World monkeys do not use dorsal carriage, and only some predominantly terrestrial Old World monkeys do so. Whereas lesser apes (which are highly arboreal) do not use dorsal carriage, arboreal as well as more terrestrial great apes commonly carry their infants dorsally. These findings indicate that simple arboreality or terrestriality is inadequate to explain dorsal carriage by monkeys. Infants of small- to medium-sized New World monkeys have relatively high birth weight compared with maternal weight, and are most likely to be carried dorsally than ventrally even on the first postnatal day. In contrast, infants of large-bodied New World monkeys are carried ventrally first and then dorsally up to the end of their second year, albeit increasingly infrequently. Among Old World monkeys, no association was found between mode of infant transport and birth weight relative to maternal weight, but some terrestrial Old World monkeys displaying dorsal carriage tend to do so with older infants, indicating that such behavior enables the mother to transport the infant with lower energy expenditure. Among terrestrial Old World monkeys, infants with distinctive natal coat colors are rarely carried dorsally until the natal coat color changes to adult coloration: infants with distinctive coat colors clinging to the backs of carriers could be highly visible and thus vulnerable to predation. Dorsal carriage by mothers may prolong the affiliative mother–infant relationship.