The effect of monoterpenes on astaxanthin production by a mutant ofPhaffia rhodozyma

Summary The total pigment and astaxanthin content ofPhaffia rhodozyma increased with increasing concentrations -pinene up to 500 l -pinene/l. Above this concentration the total pigment and astaxanthin content as well as the biomass production decreased. The addition of 500 l -pinene/l increased the total pigment content from 1652 g/g to 2201 g/g and the astaxanthin content from 1554 g/g to 1883 g/g. A sharp decrease in maximum specific growth rate occurred above 150 l -pinene/l.     

No linkage to the 3β-HSD gene cluster in a kindred affected with 3β-hydroxy-Δ5-C27steroid dehydrogenase deficiency and early onset hepatic failure

We studied the segregation of the genes for 3-hydroxy-C_19/21-steroid dehydrogenase types I and II (3-HSD I and II) in a consanguineous family affected with 3-hydroxy-⁵-C₂₇steroid dehydrogenase (3-OH-C₂₇-SD) deficiency. The results show that the C₂₇ and C_19/21 steroid dehydrogenase activities are encoded by distinct genes that are not in genetic linkage. Further kindreds would assist in screening for linkage of 3-OH-C₂₇-SD to other members of the 3-hydroxysteroid dehydrogenase gene family.     

Purification and characterization of flavone-specific β-glucuronidase from callus cultures of Scutellaria baicalensis Georgi

-Glucuronidase from callus cultures of Scutellaria baicalensis Georgi was purified to apparent homogeneity by fractionated ammonium-sulfate precipitation and chromatography on diethylaminoethyl-cellulose, hydroxylapatite and baicalin-conjugated Sepharose 6B. A 650-fold purification was obtained by this purification system. When subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis the purified protein migrated as a single band with a molecular mass of 55 kDa. We determined that the native enzyme has a molecular mass of 230 kDa using gel-filtration chromatography. These results suggested that the enzyme exists as a homotetramer composed of four identical 55-kDa subunits. The enzyme showed a broad pH optimum between 7.0 and 8.0. The K _m values were 9 M, 10 M, 30 M and 40 M for luteolin 3 -O--d-glucuronide, baicalin, wogonin 7-O--d-glucoronide and oroxlin 7-O--d-glucuronide, respectively. The enzyme was most active with flavone 7-O--d-glucuronides.Abbreviations BA N⁶-benzyladenine - 2,4-D 2,4-dichlorophenoxyacetic acid - pI isoelectric point - R _t retention time     

Comparative residual toxicities of pesticides to the predator Agistemus industani (Acari: Stigmaeidae) on citrus in Florida

Residual toxicities of registered and selected experimental pesticides used on citrus against Agistemus industani Gonzalez (Acari: Stigmaeidae) were compared. Pesticides considered highly toxic to A. industani were: abamectin 0.15 EC at 731ml/ha+FC 435-66 petroleum oil at 46.8l/ha, pyridaben 75WP at 469g/ha, ethion 4EC at 7.01l/ha+FC 435-66 petroleum oil at 46.8l/ha, propargite 6.55 EC at 3.51l/ha, chlorfenapyr 2SC at 1.46l/ha applied alone or in combination with FC 435-66 petroleum oil at 46.8l/ha, sulphur 80DF at 16.81kg/ha, dicofol 4EC at 7.01l/ha, fenbutatin oxide 50WP at 2.24kg/ha, benomyl 50WP at 2.24kg/ha, benomyl 50WP at 1.68kg/ha+ferbam 76 GF at 5.60kg/ha, ferbam 76GF at 11.21kg/ha, neem oil 90EC at 46.8l/ha, and copper hydroxide DF (40% metallic copper) at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha. Pesticides that were moderately to slightly toxic included: copper sulphate 98% at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha, fenbuconazole 2F at 280ml/ha+FC 435-66 petroleum oil at 46.8l/ha, FC 435-66 petroleum oil applied alone at 46.8l/ha or 23.4l/ha, and diflubenzuron 25WP at 1.40kg/ha. Pesticides that were non-toxic included: fenbuconazole 2F at 585ml/ha, malathion 57EC at 5.85l/ha, FC 435-66 petroleum oil at 46.8l/ha, carbaryl 80S at 3.36kg/ha, chlorpyrifos 4EC at 4.68l/ha, and formetanate 92SP at 1.12kg/ha. Understanding the toxic effects of field weathered pesticides against key predacious mite species is important for effective IPM. The results of this study provide a comparison of direct and indirect toxic effects of various pesticides to A. industani under field conditions.     

Polymerization of β-amino Acids in Aqueous Solution

We have compared carbonyl diimidazole (CDI) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) as activating agents for the oligomerization of negatively-charged - and -amino acids in homogeneous aqueous solution. -Amino acids can be oligomerized efficiently using CDI, but not by EDAC. -Amino acids can be oligomerized efficiently using EDAC, but not by CDI. Aspartic acid, an - and -dicarboxylic acid is oligomerized efficiently by both reagents. These results are explained in terms of the mechanisms of the reactions, and their relevance to prebiotic chemistry is discussed.     

Effect of androgens on histochemical fibre type

Summary The temporal muscles of the guinea pig show a sexual differentiation reflected in their histochemical enzyme pattern. Using histochemical methods for mitochondrial (SDH, -GPDH), and glycolytic enzymes (phosphorylase, LDH) it could be shown, that in adult animals the male muscle is a white muscle with marked activity of glycolytic enzymes, the female muscle a red muscle displaying high activity of mitochondrial enzymes. This differential enzyme pattern can be converted by the application of testosterone to the female type during the postnatal development. The male sex hormone thus affects the histochemical enzyme pattern of the muscle, converting the red, female into a white, male muscle in the female guinea pig.     

Soret spectroscopic and molecular graphic analysis of human semi-beta-hemoglobin formation

The interaction of heme-free (^o) and heme-containing (^h) chains of human hemoglobin has been monitored in 0.1 M potassium phosphate buffer, pH 7 or 8, at [5°C. Soret zero and first-derivative spectra were consistent with a uniform association reaction. Stopped-flow investigations demonstrated association rates on the order of 10⁷ M^–1 s^–1. This was 100-fold more rapid than the reported rate of combination of ^h and ^h proteins. This encounter-like rate of semi--hemoglobin (^oh) formation was increased by raising the pH from 7 to 8. pH change is known to affect the spatial arrangement of AB—GH helical entities. Molecular graphic analysis of modeled ^o protein superimposed over native ^h protein revealed an apo Mb-like structure with well-defined AB—GH segments. Repositioning of these core helical segments, resulting in increased conformational freedom of the ₁₁ interface, was apparently responsible for the enhanced association properties of the ^o protein.     

Ritual,the state,and the transformation of emotional discourse in Iranian society

This paper explores the social and cultural organization of Iranian emotional discourse and its transformation in post-revolutionary Iran. First, the Moharram dramas we participated in during field research are described, indicating how these performances organized a prototypical view of the social order, the self, and the passions. Using Kapferer's distinction between transcendental and transformative rituals, we argue that these dramas were traditionally organized as transcendental rites. Second, data on grieving rituals and depressive illness among Iranians is introduced, focusing on the transformative qualities of mourning rites and suggesting an interpretation of depression as a failure of the work of culture. Third, the appropriation of these symbolic forms of society, self, and the emotions by the current Iranian Islamic state and the role of the state in defming the meaning and legitimacy of emotions and their expression is analyzed.     

γδ T-cell receptor repertoire in human peripheral blood and thymus

T-cell clones expressing the T-cell receptor (Tcr) were generated from peripheral blood lymphocytes (PBLs) and from a thymus sample. In the panel of ten thymus-derived clones, four Tcr phenotypes [as defined by the reaction of monoclonal antibodies (mAbs) directed against known V and V regions] were identified. All the clones lacked expression of the V3 V region, while seven clones were V1+ . V1 was found in combination with V9 or with undefined VVregions. In addition, two other Tcr phenotypes were identified on these clones: V9⁺ V1^– V3^– and V9^– V1^– V3^– One of the clones expressed CD4 and another was CD8positive. The remaining clones were CD4^– CD8^–. In the panel of 76 PBL-derived, Tcr-bearing clones, five Tcr phenotypes could be identified. In contrast to the thymus-derived clones, 30% of the clones were V3⁺ whereas V1 was expressed by a minority of the clones only. One clone was CD4-positive and approximately 30% of the clones were CD8-positive. Four of the five mAb-defined Tcr phenotypes could be identified on both thymus and PBL-derived T-cell clones. However, biochemical analysis of the Tcrs demonstrates differences in the usage of Ct- and C2-encoded y chains by T cells derived from the thymus and PBLs. The results therefore indicate that, at the clonal level, similarities and differences exist between the Tcr repertoires expressed in the thymus and by PBLs. Furthermore, they indicate that combinatorial Tcr heterogeneity is larger than has so far been described. The receptor diversity, combined with the potential of Tcr+ cells to express CD4 or CD8, indicates that these cells are a heterogeneous population that might mediate a number of immune functions.     

Inactivation of voltage-dependent calcium current in an insulinoma cell line

We have studied the mechanism of Ca current inactivation in the -cell line HIT-T15 by conventional and perforated patch recording techniques, using two pulse voltage protocols and a combination of current and tail current measurements. In 5 mM Ca, from a holding potential of - 80 mV, the maximum current showed a complex time course of inactivation: a relatively fast, double exponential inactivation (_h1 12 ms and _h2 60 ms) and a very slowly inactivating component ( > 1 s). The faster component (_h1) was due to the voltage-dependent inactivation of a low-threshold-activated (LVA), T-type current, which deactivates more slowly ( 3–5 ms) than the other components ( 0.2–0.3 ms). The intermediate component (_h2) was due to the Ca-dependent inactivation of a portion of the high-threshold-activated (HVA) current. A saturating dose of the dihydropyridine (DHP) nifedipine (10 M) did not affect the LVA current, but inhibited by 68 ± 5% the transient, Ca-sensitive portion of the HVA current and by 33 ± 12% the long lasting component. We suggest that three components of the calcium current can be resolved in HIT cells and the main target of DHPs is a HVA current, which inactivates faster than the DHP-resistant HVA component and does so primarily through calcium influx. Correspondence to: C. Marchetti     

Laser kinetic spectroscopy studies of the bimolecular oxygenation of alpha- and beta-subunits within the R-state of human hemoglobin

Bimolecular oxygenation of tri-liganded R-state human hemoglobin (HbA) is described by bi-exponential kinetics with association rate constants k = 27.2 ± 1.3 (M·sec)^-1 and k = 62.9 ± 1.6 (M·sec)^-1. Both the observed processes have been assigned to the bimolecular oxygenation of - and -subunits of the native tetrameric protein by molecular oxygen. The quantum yields of photodissociation within the completely oxygenated R-state HbA are = 0.0120 ± 0.0017 and = 0.044 ± 0.005 for - and -subunits, respectively. The oxygenation reactions of isolated ^PCMB- and ^PCMB-hemoglobin chains are described by mono-exponential kinetics with the association rate constants k = 44 ± 2 (M·sec)^-1 and k = 51 ± 1 (M·sec)^-1, respectively. The quantum yields of photodissociation of isolated ^PCMB- and ^PCMB-chains (0.056 ± 0.006 and 0.065 ± 0.006, respectively) are greater than that observed for appropriate subunits within the R-state of oxygenated HbA.     

A Comment on La Vaque and Rossiter

The paper by La Vaque and Rossiter recommends that placebo-controlled trials only be conducted when best proven treatments are not available. In this comment, I review evidence suggesting that identifying best proven treatments is a complex task involving many variables and that making such a decision entails many real-world difficulties.     

Contextualizing Images in Dreams and Daydreams

A contextualizing image (CI) is a powerful central image of a dream which appears to contextualize (provide a picture-context for) the dreamer's emotion. For instance, dreamers who have experienced any serious traumatic event sometimes dream, I was overwhelmed by a tidal wave. This appears to picture their feeling of terror and/or vulnerability.A scoring system for CIs is examined here and is applied to dreams and daydreams supplied by 40 students. Two raters scoring dreams on a blind basis showed good inter-rater reliability. Recent dreams were shown to have more as well as more intense CIs than recent daydreams; likewise, dreams that stand out had more intense CIs than daydreams that stand out. Students with thin boundaries had more and more intense CIs than students with thick boundaries in their recent dreams and nightmare, but not so clearly in dreams and nightmares that stand out. The emotions judged as contextualized by the powerful images tended towards fear/terror and helplessness/vulnerability in dreams (especially in dreams that stand out) whereas emotions contextualized by images in daydreams showed a wide range with no clusters.     

Cholinesterases and cell proliferation in “nonstratified” and “stratified” cell aggregates from chicken retina and tectum

Summary Dissociated single cells from chicken retina or tectum kept in rotation-mediated cell culture aggregate, proliferate and establish a certain degree of histotypical cellto-cell relationships (sorting out), but these systems never form highly laminated aggregates (nonstratified R- and T-aggregates). In contrast, a mixture of retinal plus pigment epithelial cells forms highly stratified aggregates (RPE-aggregates, see Vollmer et al. 1984). The present comparative study of stratified and nonstratified aggregates enables us to investigate the process of cell proliferation uncoupled from that of tissue stratification. Here we try to relate these two basic neurogenetic processes with patterns of expression of cholinesterases (AChE, BChE) during formation of both types of aggregates.During early aggregate formation, in both stratified and nonstratified aggregates an increased butyrylcholinesterase activity is observed close to mitotically active cells. Quantitatively both phenomena show their maxima after 2–3 days in culture. In contrast, AChE-expression in all systems increases with incubation time. In nonproliferative areas, in the center of RPE-aggregates, the formation of plexiform layers is characterized initially by weak BChE and then strong AChE-activity. These areas correspond with the inner (IPL) and outer (OPL) plexiform layers of the retina in vivo. Although by sucrose gradient centrifugation we find that the 6S- and the fiber-associated 11S-molecules of AChE are present in all types of aggregates, during the culture period the ratio of 11S/6S-forms increases only in RPE-aggregates, which again indicates the advanced degree of differentiation within these aggregates.It is thus demonstrated that cholinesterases first correlate with neuronal cell proliferation and later with stratification, which indicates functions of both enzymes during both developmental periods.Abbreviations AChE acetylcholinesterase - BChE butyrylcholinesterase - iso-OMPA specific inhibitor of BChE - BW 284C51 specific inhibitor of AChE - IPL inner plexiform layer - OPL outer plexiform layer     

Protein engineering in the α-amylase family: catalytic mechanism,substrate specificity,and stability

Most starch hydrolases and related enzymes belong to the -amylase family which contains a characteristic catalytic (/)₈-barrel domain. Currently known primary structures that have sequence similarities represent 18 different specificities, including starch branching enzyme. Crystal structures have been reported in three of these enzyme classes: the -amylases, the cyclodextrin glucanotransferases, and the oligo-1,6-glucosidases. Throughout the -amylase family, only eight amino acid residues are invariant, seven at the active site and a glycine in a short turn. However, comparison of three-dimensional models with a multiple sequence alignment suggests that the diversity in specificity arises by variation in substrate binding at the loops. Designed mutations thus have enhanced transferase activity and altered the oligosaccharide product patterns of -amylases, changed the distribution of -, - and -cyclodextrin production by cyclodextrin glucanotransferases, and shifted the relative -1,4:-1,6 dual-bond specificity of neopullulanase. Barley -amylase isozyme hybrids and Bacillus -amylases demonstrate the impact of a small domain B protruding from the (/)₈-scaffold on the function and stability. Prospects for rational engineering in this family include important members of plant origin, such as -amylase, starch branching and debranching enzymes, and amylomaltase.Abbreviations CGTase cyclodextrin glucanotransferase - SBD starch binding domain - TAA taka-amylase A - TIM triose-phosphate isomerase. The mutations are described with the one-letter code, i.e. D164A is a mutant in which A in the mutant is substituted for D in the wild-type.     

Heterochromatin variation in Cryptobothrus chrysophorus

The endemic grasshopper Cryptobothrus chrysophorus is widely distributed throughout S.E. Australia and its populations display an extensive and spectacular pattern of autosomal variation. While the standard telocentric complement of three long (L1–3), six medium (M4–9) and two short (S10–11) autosome pairs is present throughout most of its range, two quite distinct chromosome races can be defined within this species. Populations in the northern part of its distribution (northern N.S.W. and southern Queensland-northern race) are differentiated from the remainder (southern race) by fixed blocks of distal heterochromatin on autosomes M4, 5, 6, 8 and 9 and by differences in the character of the megameric M7 chromosome. Additionally, while many populations in both races show a polymorphic system of supernumerary segments on the two smallest autosomes (S10–11), that found in the northern race is both more variable and more complex. On the other hand all the populations of the southern race we have examined are polymorphic for a series of centric shifts which convert telocentrics into acro- or meta-centrics. These occur more commonly in the megameric M7 and the two smallest autosomes (S10–11) although in one population (Forbes Creek, N.S.W.) at least 12 different shifts involving 8 of the autosomes (L3, M4, 5, 6, 7, 8, 9 and S10) are known. By contrast, in the northern erace only the small autosomes (S10–11) show centric shifts. These several floating and fixed variants thus involve all chromosomes of the standard set other than the two largest autosomes (L1–2) and the X-chromosome, which appear to be invariate. Finally, morphologically distinct supernumerary (B) chromosomes, intermediate in size between the standard S10 and the M9 elements, are found in both races but are especially common in Tasmania, the most southerly point of the species range. These B-chromosomes are partly heterochromatic and partly euchromatic so that they too add to the considerable heterochromatin variation in this species.     

A new base substitution in the 5′ regulatory region of the humanAγ globin gene is linked with the βs gene

A new TA base substitution, identified inside the 5 regulatory region of the human^A globin gene (^A –499 T A), is reported. This nucleotide change was found to be linked incis with the mutation producing sickle cell anemia (CD6 GAGGTG: ^s gene).     

Identification and characterization of the functional alpha origin of DNA replication of the R6K plasmid and its relatedness to the R6K beta and gamma origins

Summary The functional R6K origin is composed of two DNA elements, one of 580 bp carrying the origin sequences and the other of 277 bp containing the seven 22 bp direct repeats previosly identified as also required for and origin activity. These two genetic elements are separated by approximately 3,000 bp of R6K sequences which are dispensable for origin activity. The function of the origin depends on the presence in cis of the 580 bp and the 277 bp fragments and requires that they be oriented as in the intact R6K. Activation of the origin depends on the R6K replication initiation protein .Within the 580 bp of the origin, there is a sequence of 98 bp which appears as an inverted repeat of 96 bp in the replicon. Deletion of the 96 bp or 98 bp results in inactivation of the and the origins respectively. These long repeats are palindromic and it is suggested that these may serve as the recognition signals for initiation of DNA replication in the and the origins of R6K. DNA homology analysis performed on , and origin sequences, also reveals 10–23 bp sequences in the and the origins that are related to the family of 22 bp direct repeats in the origin which were shown previously to be binding sites for the protein.