Expression of micF involved in porin synthesis in Escherichia coli: two distinct cis-acting elements respectively regulate micF expression positively and negatively

micF RNA, whose sequence is highly complementary to a 5'-portion of ompF mRNA, has been implicated in the osmoregulation and thermoregulation of the ompF porin gene in Escherichia coli. To define and characterize cis-acting regulatory regions upstream of the micF promoter, a series of deletions of the micF promoter fused to the lacZ gene were constructed. Two distinct regions, which function differently, were identified as cis-acting regulatory elements, namely, one responsible for OmpR-dependent activation and the other for OmpR-independent repression of micF expression. The former contains the OmpR-binding site, which simultaneously regulates both the genes, micF and ompC, in response to the medium osmolarity. The latter may be involved in an unknown regulatory process of micF expression.     

Influence of rainfall on sleeping site choice by a group of anubis baboons (Papio anubis)

For diurnal nonhuman primates, shifting among different sleeping sites may provide multiple benefits such as better protection from predators, reduced risk of parasitic infection, and closer proximity to spatially and temporally heterogeneous food and water. This last benefit may be particularly important in sleeping site selection by primates living in savanna‐woodlands where rainfall is more limited and more seasonally pronounced than in rainforests. Here, we examined the influence of rainfall, a factor that affects food and water availability, on the use of sleeping sites by anubis baboons (Papio anubis) over two 13‐month study periods that differed in rainfall patterns. We predicted that during wet periods, when food and water availability should be higher, the study group would limit the number of sleeping sites and would stay at each one for more consecutive nights than during dry periods. Conversely, we predicted that during dry periods the group would increase the number of sleeping sites and stay at each one for fewer consecutive nights as they searched more widely for food and water. We also predicted that the group would more often choose sleeping sites closer to the center of the area used during daytime (between 07:00 and 19:00) during wet months than during dry months. Using Global Positioning System data from collared individuals, we found that our first prediction was not supported on either monthly or yearly timescales, although past monthly rainfall predicted the use of the main sleeping site in the second study period. Our second prediction was supported only on a yearly timescale. This study suggests that baboons’ choice of sleeping sites is fluid over time while being sensitive to local environmental conditions, one of which may be rainfall.     

Existence of a Novel Hemagglutinin Having No Protease Activity in Vibrio mimicus

The protease elaborated by Vibrio mimicus is known to possess hemagglutinating ability to chicken erythrocytes, the well-known HA/protease. A non-protease hemagglutinin (HA) with strong agglutinating ability towards rabbit erythrocytes was obtained from 32 hr culture supernatant of a pathogenic environmental strain of V. mimicus. This HA (V. mimicus HA: VMHA) appeared stable at relatively higher temperature and agglutinated the erythrocytes from rabbit, guinea pig and mouse but not the erythrocytes from chicken, bovine, horse and sheep. Simple sugars, metal ions and chelating agents failed to inhibit the activity of VMHA. The activity of VMHA was found to be sensitive to digestion by proteolytic enzymes including HA/protease. These results provide evidence for the existence of novel HA other than HA/protease in V. mimicus.     

Irreversible inactivation of aspartate aminotransferases during transamination with L-propargylglycine

L-Propargylglycine serves as an amino acid substrate in the transamination reaction catalyzed by both cytosolic and mitochondrial aspartate aminotransferases from pig heart. Incubation of these isoenzymes with L-propargylglycine alone did not result in the inactivation of these enzymes. However, the presence of 2-oxoglutarate or pyruvate caused gradual irreversible inactivation of these isoenzymes. The inactivation was greatly accelerated by the presence of formate ion. Inactivation of both isoenzymes with L-[2-¹⁴C]propargylglycine resulted in stoichiometric incorporation of the radioactive molecule. Drastic changes in the absorption and circular dichroic spectra of the enzymes which took place during the inactivation also indicated that the modification by L-propargylglycine is restricted to the active site of these isoenzymes.     

A New Mint (Variety of Mentha aquatica L.) Containing (—)-Isopinocamphone as a Major Constituent of Essential Oil

Certain strains of Rhodotorula were found capable of utilizing L-phenylalanine as a sole carbon and nitrogen source and of accumulating ether-soluble metabolite in the cultured broth. The metabolite was isolated and identified as trans-cinnamic acid. The nonoxidative deamination of phenylalanine to trans-cinnamic acid was catalyzed by dried cells, acetone-dried cells or intact cells with surface active agents. The distribution of phenylalanine ammonia-lyase activity in yeasts was investigated. It was found that the enzyme activity specifically occurred in Rhodotorula and that the formation of enzyme was enhanced by culturing on the medium supplemented with phenylalanine.     

Genetic Variations in the Human Cannabinoid Receptor Gene Are Associated with Happiness

Happiness has been viewed as a temporary emotional state (e.g., pleasure) and a relatively stable state of being happy (subjective happiness level). As previous studies demonstrated that individuals with high subjective happiness level rated their current affective states more positively when they experience positive events, these two aspects of happiness are interrelated. According to a recent neuroimaging study, the cytosine to thymine single-nucleotide polymorphism of the human cannabinoid receptor 1 gene is associated with sensitivity to positive emotional stimuli. Thus, we hypothesized that our genetic traits, such as the human cannabinoid receptor 1 genotypes, are closely related to the two aspects of happiness. In Experiment 1, 198 healthy volunteers were used to compare the subjective happiness level between cytosine allele carriers and thymine-thymine carriers of the human cannabinoid receptor 1 gene. In Experiment 2, we used positron emission tomography with 20 healthy participants to compare the brain responses to positive emotional stimuli of cytosine allele carriers to that of thymine-thymine carriers. Compared to thymine-thymine carriers, cytosine allele carriers have a higher subjective happiness level. Regression analysis indicated that the cytosine allele is significantly associated with subjective happiness level. The positive mood after watching a positive film was significantly higher for the cytosine allele carriers compared to the thymine-thymine carriers. Positive emotion-related brain region such as the medial prefrontal cortex was significantly activated when the cytosine allele carriers watched the positive film compared to the thymine-thymine carriers. Thus, the human cannabinoid receptor 1 genotypes are closely related to two aspects of happiness. Compared to thymine-thymine carriers, the cytosine allele carriers of the human cannabinoid receptor 1 gene, who are sensitive to positive emotional stimuli, exhibited greater magnitude positive emotions when they experienced positive events and had a higher subjective happiness level.     

Studies of the Essential Oil of Mentha rotundifolia

Rotundifolone, a new terpenic ketone, C₁₀H₁₄O₂ has been isolated from the essential oil of M. rotundifolia in Japan. This ketone is highly dextro-rotatory, and has a low, melting point 27.5° The wave lengths of the ultraviolet absorption maxima of rotundifolone and its semicarbazone are 260 mμ (log ε = 3.95) and 273 mμ (log ε = 4.12) respectively. This indicates that rotundifolone has an α,β-unsaturated carbonylic system.     

Relationship between Stereoisomerism and Biological Activity of Pyrethroids

Higher homologous acids of chrysanthemic acid described in the previous papers were esterified with (±)-allethrolone. The toxicity of these esters and the related compounds were evaluated by the topical application method to Musca domestica vicina Macq. The allethronyl homochry-santhemate (entry Nos. 4, 5) was shown to be toxic and the dextrorotatory form was far more toxic than the laevorotatory one. Further elongation of the ester linkage resulted in a loss of toxicity. The cyclobutane carboxylic acid ester (entry No. 10) was shown to be toxic and so, the cyclopropane ring might be replaced to some extent by the cyclobutane ring, provided the other requirements were fulfiled. However, further elongation of the ester linkage also reduced the toxicity. The lactones (entry Nos. 12–16) obtained by the hot sulfuric acid treatment were non-toxic.