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BACKGROUND/OBJECTIVES: As taste preferences may be associated with obesity, the present study investigated whether obese subjects presented heightened liking for the sensations of sweet, salt and fat. SUBJECTS/METHODS: Liking scores were determined by a questionnaire including 83 items on liking for sweet or fatty foods, and the preferred extent of seasoning with salt, sweet or fat. Data from 46 909 adults included in the French web-based observational cohort of the Nutrinet-Sante study were collected and weighted according to the national population census. Relationships between liking scores and body mass index (BMI) as categorical or linear explanatory variable were assessed separately by gender using covariance and linear regression analyses, adjusted for age, education level, living area, smoking and alcohol. RESULTS: Overall liking scores for salt and fat were linearly positively linked to BMI in men and women (P [less than or equal to] 0.001) and were higher in obese than in normal-weight individuals. The score difference between BMI categories was greater in women for fat liking only. For sweet liking, results differed between gender and compounding factors. Liking for added sugar and sweet foods was positively linked to BMI in women unlike in men; liking for natural sweetness was negatively linked to BMI in both genders. CONCLUSIONS: This study demonstrates that the relationship between liking and BMI differs according to the gender in its magnitude for fat and in its nature for sweet, unlike that for salt. Liking for sweet and fat may be linked to overconsumption of the corresponding foods, especially in women. This warrants further investigation. European Journal of Clinical Nutrition (2015) 69, 40-46;doi: 10.1038/ejcn.2014.139;published online 30 July 2014, INTRODUCTION Chronic diseases including obesity, diabetes and cardiovascular diseases have become a worldwide burden, especially in developed and rapidly urbanized areas. (1) Among complex multifactorial causes, overconsumption of salty, sweet [...]

Background/Objectives: Lower-income subgroups consume fewer servings of fruit and vegetables (FVs) compared with their more advantaged counterparts. To overcome financial barriers, FV voucher delivery has been proposed. Subjects/Methods: In a 12-month trial, 302 low-income adults 18-60 years old (defined by evaluation of deprivation and inequalities in health examination centers, a specific deprivation score) were randomized into two groups: dietary advice alone ('advice'), or dietary advice plus FV vouchers ('FV vouchers') (10-40 euros/month) exchangeable for fresh fruits and vegetables. Self-reported data were collected on FV consumption and socioeconomic status at baseline, 3, 9 and 12 months. Anthropometric and blood pressure measurements were conducted at these periods, as well as blood samples obtained for determination of vitamins. Descriptive analyses, multiple linear regression and logistic regression were performed to evaluate the impact of FV. Results: Between baseline and 3-month follow-up, mean FV consumption increased significantly in both the 'advice' (0.62 [+ or-] 1.29 times/day, P = 0.0004) and 'FV vouchers' groups (0.74 [+ or-] 1.90, P = 0.002), with no difference between groups. Subjects in the FV vouchers group had significantly decreased risk of low FV consumption ( Conclusion: In the low-income population, FV voucher delivery decreased the proportion of low FV consumers at 3 months. Longer-term studies are needed to assess their impact on nutritional status. European journal of Clinical Nutrition (2012) 66, 369-375; doi: 10.1038/ejcn.2011.173; published online 12 October 2011 Keywords: fruit and vegetables; fruit and vegetable vouchers; low income, Introduction A diet poor in fruit and vegetables (FVs) is associated with an increased risk of certain cancers and heart disease and stroke (Hung et al., 2004; Dauchet et al., [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jue.2010.03.006 Byline: T. Mayer (a), I. Mejean (b), B. Nefussi (c) Keywords: Location choice; Multinational firms; Agglomeration economies; Conditional logit model Abstract: In this paper we combine two traditions in the analysis of firms' location patterns. One led by trade economists who try to understand why do firms invest abroad, and another one led by urban/regional economists, who frequently use patterns of inter-regional or inter-city choices to estimate agglomeration economies. We contribute to the trade-motivated set of papers on location choices by adding the domestic country in the choice set, while accounting for firm's heterogeneity in the choices. Our econometric results using French firm-level data show an important 'home bias' in manufacturing investment decisions. A crucial finding, which bridges with our contribution to the agglomeration literature, is that the spatial clustering of affiliates belonging to the same industrial group accounts for the lion's share of this home bias. Author Affiliation: (a) Sciences-Po, CEPII, and CEPR. CEPII, 9 rue Pitard, 75015 Paris, France (b) IMF, Ecole Polytechnique and CEPR. Ecole Polytechnique, Departement d'Economie, 91128 Palaiseau Cedex, France (c) INSEE, DGTPE, 139 rue de Bercy, 75012 Paris, France Article History: Received 10 November 2008; Revised 19 March 2010

Determinants of fruit and vegetable consumption, including affordability and attitudes, have been poorly investigated, especially in European deprived populations. Our objective was to analyze various determinants of low consumption of fruits and vegetables in disadvantaged participants. Our participants were randomized into 2 groups, 1 which received nutritional advice alone and 1 that also received vouchers that were exchangeable for fruits and vegetables during a 12-mo period. Socioeconomic characteristics, food insufficiency, affordability, and motivation for eating fruits and vegetables were assessed. A short FFQ was administered. Determinants of consumption of doi: 10.3945/jn.109.118273

Background/Objectives: Few studies in Europe have examined the relationship of sociodemographic and economic factors with diet in deprived populations. We analysed the association between socioeconomic characteristics and consumption of different food groups in food aid users. Subjects/Methods: A cross-sectional study was conducted among food aid users in four urban French zones (n = 1664). Associations of sociodemographic and economic factors and food aid use with frequency of consumption of the main food groups were tested using multivariate logistic regression models accounting for sampling weights. Results: Both migrant status and consumption of fewer than three daily meals were associated with risk of low frequency of starchy food consumption (< 3 times per day). Migrant status was also associated with low frequency of consumption of fruits and vegetables (< 3.5 times per day) and dairy products ( Conclusions: Economic level and other social characteristics were associated with an unhealthy diet within this deprived French population. European Journal of Clinical Nutrition (2010) 64, 374-382; doi: 10.1038/ejcn.2009.153; published online 20 January 2010 Keywords: food aid; food supply; dietary behaviour; socioeconomic discrepancies; deprived population, Introduction Diet is influenced by sociodemographic, economic and cultural factors. It is well documented that low socioeconomic status, a poor education level and unemployment are associated with an unhealthier diet [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.regsciurbeco.2009.09.005 Byline: Isabelle Mejean (a), Lise Patureau (b) Keywords: Minimum wage; Home Market Effect; Firms' location decisions Abstract: We consider the impact minimum wage laws have on firms' location choices in a new economic geography model with exogenous minimum wage constraints. The minimum wage policy has a twofold influence on the relative attractiveness of the home country, simultaneously affecting its relative cost competitiveness and its aggregate income. The end effect depends on interactions between the skilled and unskilled segments of the labor market. If workers are strongly substitutable, the effect of raising low-skilled workers income is more than compensated by a drop in their employment level. Under such circumstances, a high minimum wage policy reduces the country's attractiveness by increasing production costs and reducing aggregate demand. Aggregate demand is further reduced once adjustments in skilled wages linked to international competitive pressures are taken into account. Author Affiliation: (a) Ecole Polytechnique, Department of Economics, F-91128 Palaiseau Cedex, France (b) Universite de Cergy-Pontoise, THEMA, 33 Boulevard du Port, F-95000 Cergy-Pontoise, France Article History: Received 12 February 2009; Revised 28 September 2009; Accepted 29 September 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jinteco.2009.02.008 Byline: Isabelle Mejean (a), Cyrille Schwellnus (b) Keywords: Price convergence; Firm heterogeneity; European integration Abstract: In this paper we use data on French export prices at the disaggregated firm and product level to evaluate the effect of economic integration on price convergence. We use the European integration 'experiment' and firm-level data on export prices to distinguish between two possible margins of adjustment: At the intensive margin economic integration induces different pricing strategies within the firm, whereas at the extensive margin it affects the composition of firms with different pricing strategies. In our sample price convergence is 40 percent faster in the European Union than in an appropriately defined control group. 30 percent of this effect can be attributed to the fact that a higher share of firms with a low propensity to price discriminate serve European markets. Author Affiliation: (a) Ecole Polytechnique, Department of Economics, 91128 Palaiseau Cedex, France (b) OECD, Economics Department and CEPII. OECD, 2 rue Andre-Pascal, 75775 Paris CEDEX 16, France Article History: Received 19 August 2008; Revised 23 February 2009; Accepted 23 February 2009 Article Note: (footnote) [star] Many thanks to Martine Carre, Matthieu Crozet, Jean Imbs and Daria Taglioni for helpful comments. The paper has also benefited from remarks of participants to seminars at CEPII, Ecole Polytechnique, the ELSNIT 2007 Conference in Barcelona and the CAED 2008 Conference in Budapest. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement Nr. 225551.

This paper examines the determinants of relative prices in a model combining a Harrod-Balassa-Samuelson (HBS) mechanism and an endogenous location of traded good producers. Besides the standard HBS effect, asymmetric productivity improvements in the traded good sector push new firms to enter the market. This benefits local consumers who save on trade costs and exerts an upward pressure on relative wages. As a consequence, relative prices in the traded good sector either increase or fall in general equilibrium. In a panel cointegration framework, the wage effect is shown to dominate. This means the HBS effect is strengthened by the relocation of traded good producers. Keywords: Long-run real exchange rate Balassa-Samuelson effect New Trade theory Panel cointegration JEL classification: F1 F2 F4

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2966.2008.00469.x Byline: Guillaume Gaulier (1), Amina Lahreche-Revil (2), Isabelle Mejean (3) Keywords: F12; F31; F41 Abstract: Abstract. We use a detailed database to investigate exchange-rate pass-through at the product level for a large number of countries. The empirical analysis suggests that pricing behaviours are dichotomous, with complete pass-through in around 25% of sectors and significant pricing-to-market in the remaining ones. Average long-run pass-through coefficient is close to 80%; this result hides a strong heterogeneity of pass-through behaviours across sectors. Even when composition effects are controlled for, average pass-through varies across importing countries. The econometric analysis shows that pass-through tends to be higher in volatile environments; in less developed countries; in weakly integrated markets. Abstract (Spanish): Analyse sectorielle de la transmission des mouvements de change aux prix. Cet article utilise une base de donnees detaillee pour analyser l'effet du taux de change sur les prix a l'exportation, mesures au niveau du produit. L'analyse empirique suggere que les comportements des prix sont dichotomiques: dans 25% des secteurs, les mouvements de change se repercutent entierement sur les prix a l'importation tandis que la transmission est incomplete pour les autres. Le coefficient moyen de transmission est de 80%a long terme. Ce resultat cache cependant une grande heterogeneite des comportements de transmission selon les secteurs. De plus, meme quand on standardise pour tenir compte des effets de composition, le coefficient moyen de transmission varie selon les pays importateurs. En particulier, l'analyse econometrique montre que l'effet de transmission est plus eleve i) dans les environnements volatils, ii) dans les pays moins developpes, et iii) dans les marches plus faiblement integres. Author Affiliation: (1)Banque de France (2)University of Amiens, Criisea (3)Ecole Polytechnique

Mediterranean migrant men living in France have lower mortality and morbidity than local-born populations for nutrition-related noncommunicable diseases (NR-NCD). We studied diet quality and its influence on NR-NCD in Tunisian migrants compared with 2 nonmigrant male groups: local-born French and nonmigrant Tunisians, using a retrospective cohort study. We performed quota sampling (n = 147) based on age and place of residence. Using logistic regression models, components of the Diet Quality Index-International (DQI-I) were tested as potential mediators for the effect of migration on overweight, hypertension, hypercholesterolemia, type-2 diabetes, and cardiovascular diseases (CVD). The total DQI-I score revealed good overall diet quality (~60/100) for all groups. Migrants scored higher than the French in variety, adequacy, and moderation and lower than Tunisians in overall balance. Migrants displayed a lower prevalence of overweight than French, lower prevalence of diabetes and CVD than Tunisians, and lower prevalence of hypertension and hypercholesterolemia than the 2 nonmigrant groups. No mediator was found for overweight. Diet adequacy, fruits, and vitamin C were mediators of the difference in hypercholesterolemia between migrants and French and the effect on hypertension was mediated by diet adequacy and fiber. Compared with Tunisians, the effect of migration on hypercholesterolemia was mediated by saturated fat. No mediator was found for hypertension, diabetes, or CVD. Despite increasing NR-NCD levels in both France and Tunisia, migrants appear to have conserved some healthy dietary characteristics that partly explain their difference in NR-NCD with local-born French, but other lifestyle factors may contribute to the favorable effect of migration.

The torECAD operon encoding the trimethylamine oxide (TMAO) respiratory system of Shewanella oneidensis is positively controlled by the TorS/TorR two-component system when TMAO is available. Activation of the tor operon occurs upon binding of the phosphorylated response regulator TorR to a single operator site containing the direct repeat nucleotide sequence TTCATAN4TTCATA. Here we show that the replacement of any nucleotide of one TTCATA hexamer prevented TorR binding in vitro, meaning that TorR specifically interacts with this DNA target. Identical direct repeat sequences were found in the promoter regions oftorR and of the new gene torF (SO4694), and they allowed TorR binding to both promoters. Real-time PCR experiments revealed that torR is negatively autoregulated, whereas torF is strongly induced by TorR in response to TMAO. Transcription start site location and footprinting analysis indicate that the operator site at torR overlaps the promoter -10 box, whereas the operator site at torF is centered at -74 bp from the start site, in agreement with the opposite role of TorR in the regulation of the two genes. Since torF and torECAD are positively coregulated by TorR, we propose that the TorF protein plays a role related to TMAO respiration.

The torl gene has been identified by using a genetic multicopy approach as a negative regulator of the torCAD operon that encodes the trimethylamine N-oxide reductase respiratory system in Escherichia coli. The negative effect was due to a previously unidentified small ORF (66 aa) of phage origin that we called torl for Tor inhibition. Overexpression of torl led to an 8-fold decrease of the torCAD operon transcription. This operon is positively regulated, in the presence of trimethylamine N-oxide, by a four-step phosphorelay involving the TorS sensor and the TorR response regulator. Epistatic experiments showed that Torl acts downstream of TorS and needs the presence of TorR. In vitro experiments showed that it is neither a TorR phosphatase nor a histidine kinase inhibitor and that it binds to the effector domain of TorR. Unexpectedly, Torl did not impede TorR DNA binding, and we propose that it may prevent RNA polymerase recruitment to the torC promoter. This study thus reveals a previously uncharacterized class of response regulator inhibitors.

The trimethylamine N-oxide (TMAO) reductase TorA, a DMSO reductase family member, is a periplasmic molybdoenzyme of Escherichia coli. The cytoplasmic protein TorD acts as a chaperone for TorA, allowing the efficient insertion of the molybdenum cofactor into the apoform of the enzyme prior to its secretion. This paper demonstrates that TorD is a member of a large family of prokaryotic proteins that are structurally related. Moreover, their genes generally belong to operons also encoding molybdoenzymes of the DMSO reductase family. Both the TorD and the DMSO reductase families present a similar phylogenetic organization, suggesting a co-evolution of these two families of proteins. This hypothesis is also supported by the fact that the TorD and DmsD chaperones cannot replace each other and thus appear dedicated to specific molybdopartners. Interestingly, it was found that the positive effect of TorD on TorA maturation, and the partial inhibitory effect of DmsD and homologues, are independent of the TorA signal sequence.

To gain a molecular understanding of kidney functions, we established a high-resolution map of gene expression patterns in the human kidney. The glomerulus and seven different nephron segments were isolated by microdissection from fresh tissue specimens, and their transcriptome was characterized by using the serial analysis of gene expression (SAGE) method. More than 400,000 mRNA SAGE tags were sequenced, making it possible to detect in each structure transcripts present at 18 copies per cell with a 95% confidence level. Expression of genes responsible for nephron transport and permeability properties was evidenced through transcripts for 119 solute carriers, 84 channels, 43 ion-transport ATPases, and 12 claudins. Searching for differences between the transcriptomes, we found 998 transcripts greatly varying in abundance from one nephron portion to another. Clustering analysis of these transcripts evidenced different extents of similarity between the nephron portions. Approximately 75% of the differentially distributed transcripts corresponded to cDNAs of known or unknown function that are accurately mapped in the human genome. This systematic large-scale analysis of individual structures of a complex human tissue reveals sets of genes underlying the function of well-defined nephron portions. It also provides quantitative expression data for a variety of genes mutated in hereditary diseases and helps in sorting candidate genes for renal diseases that affect specific portions of the human nephron.

Most long-path remote spectroscopic studies of the atmosphere rely on ambient light or narrow-band lasers. High-power femtosecond laser pulses have been found to propagate in the atmosphere as dynamically self-guided [...]

Research has been conducted on R67 dihydrofolate reductase. The study of the molecular steps involved in this reductase refolding and the search of the intermediates which could provide information on the folding mechanism are described.

In mammals, male sex determination starts when the Y chromosome Sry gene is expressed within the undetermined male gonad. One of the earliest effect of Sry expression is to induce upregulation of Sox9 gene expression in the developing gonad. SOX9, like SRY, contains a high mobility group domain and is sufficient to induce testis differentiation in transgenic XX mice. Before sexual differentiation, SOX9 protein is initially found in the cytoplasm of undifferentiated gonads from both sexes. At the time of testis differentiation and anti-Mullerian hormone expression, it becomes localized to the nuclear compartment in males whereas it is down-regulated in females. In this report, we used NIH 3T3 cells as a model to examine the regulation of SOX9 nucleo-cytoplasmic shuttling. SOX9-transfected cells expressed nuclear and cytoplasmic SOX9 whereas transfected cells treated with the nuclear export inhibitor leptomycin B, displayed an exclusive nuclear localization of SOX9. By using SOX9 deletion constructs in green fluorescent protein fusion proteins, we identified a functional nuclear export signal sequence between amino acids 134 and 147 of SOX9 high mobility group box. More strikingly, we show that inhibiting nuclear export with leptomycin B in mouse XX gonads cultured in vitro induced a sex reversal phenotype characterized by nuclear SOX9 and anti-Mullerian hormone expression. These results indicate that SOX9 nuclear export signal is essential for SOX9 sex-specific subcellular localization and could be part of a regulatory switch repressing (in females) or triggering (in males) male-specific sexual differentiation.

Research has been conducted on trimethylamine oxide, an organic compound used by some bacteria to grow. Results indicate that Shewanella oneidensis's trimethylamine oxide reductase production has been induced by trimethylamine oxide and repressed by oxygen.

Byline: Lydie Guermani-Nicolle (1), Christian Villaume (1), Hwei-Ming Bau (1), Annie Schwertz (1), Jean-Pierre Nicolas (1), Luc Mejean (1) Keywords: Casein; Cholesterolemia; Fasting; Glycemia; Soybean; Triglyceridemia Abstract: Numerous factors affect plasma cholesterol and, therefore, representpotential interferences with the specific effects of diet on lipid metabolism.After casein intake, serum cholesterol levels depend on many experimentalconditions in rats, such as the type of casein, the presence or absence ofcholesterol in the diet, the age and strain of rat, the diet composition, thenutritional status. The effect of fasting duration on selected parameters wasstudied in adult male Wistar rats fed a 20% casein and 1% cholesterol-based diet. No changes were observed in total serum, lipoproteins-B andHDL cholesterol and in triglyceride values after an 8 h-fast compared tonon-fasted animals. A significant decrease was induced in total andlipoproteins-B cholesterol with a 12 h-fast. A prolonged fast resulted ina significant decrease in these parameters and in triglycerides and inHDL-cholesterol levels.Fasted animals fed heated soybean meal instead of casein did not display amarked decrease in serum lipids. It appeared that the fasting effect wasmore marked in animals fed casein than in animals fed soybeans. Theseresults showed the importance of experimental conditions such as nutritional status ofanimals when blood samples are taken in studies of the hypocholesterolemiceffect of soy protein compared to casein. Author Affiliation: (1) INSERM Unite 308, 38 rue Lionnois, 54 000, Nancy, France Article History: Registration Date: 03/10/2004

Research has been conducted on the protein-protein recognition. The kinetic aspects of this recognition have been investigated to understand the molecular mechanism of association.

Results show that the unorthodox sensor TorS dephosphorylates TorR-P in Escherichia coli. Data indicate that the receiver D1 and secondary transmitter H2 domains of TorS participate in the down regulation of the tor operon.

Two molecular techniques can detect 10 to 1,000 times more cytochrome cd(sub 1) denitrifying bacteria in sediment or water samples than traditional cultivation methods. The methods are most-probably-number PCR and competitive PCR, both using the cd3F-cd4R PCR primer set.

Research has been conducted on the torCAD operon encoding Escherichia coli trimethylamine N-oxide respiratory system. Results indicate that torR gene is negatively autoregulated.

Byline: Dominique Joly (1), Philippe Rieu (5), Arnaud Mejean (3), Marie-France Gagnadoux (2), Michel Daudon (4), P. Jungers (1) Keywords: Key wordsaCystine urolithiasis; Cystinuria; D-Penicillamine; Tiopronin Abstract: Cystine urolithiasis is the only clinical expression of cystinuria, an autosomal recessive genetic defect of the transepithelial transport of cystine and other dibasic amino acids in the kidney. Stones form due to the increased excretion of cystine, which is poorly soluble at normal urine pH. Cystine stones are often resistent to extracorporeal shock wave lithotripsy, so that percutaneous surgery or ureteroscopy are the preferred techniques of stone extraction. Medical preventative treatment is based on high diuresis (aY=1.5 l/m.sup.2 per day) well distributed throughout the day and night, and urine alkalinization up to pH 7.5 by means of sodium bicarbonate and/or potassium citrate. When these basal measures are ineffective at preventing stone recurrence or dissolving pre-existing stones, sulfhydryl agents such as D-penicillamine or tiopronin, which form highly soluble mixed disulfides with cystine moieties, are to be added to urine dilution and alkalinization, especially when cystine excretion is in excess of 750 mg/day (3 mmol/day). Frequent clinical and ultrasound follow-up is needed to encourage patient compliance and assess efficacy and tolerance of treatment. Author Affiliation: (1) Department of Nephrology, Hopital Necker-Enfants Malades, 149, rue de Sevres, F-75015 Paris, France e-mail:paul.jungers@nck.ap-hop-paris.fr Tel.: +33-1-4449-5412, Fax: +1-33-1-4449-5450, FR (2) Department of Pediatric Nephrology, Hopital Necker-Enfants Malades, Paris, France, FR (3) Department of Urology, Hopital Necker-Enfants Malades, Paris, France, FR (4) Department of Biochemistry, Hopital Necker-Enfants Malades, Paris, France, FR (5) INSERM U 507, Hopital Necker-Enfants Malades, Paris, France, FR Article note: Received: 5 January 1999 / Revised: 1 March 1999 / Accepted: 3 March 1999

A novel gene called thrH encodes a protein with an in vivo homoserine-kinase-like activity in Pseudomonas aeruginosa when expressed in Escherichia coli thrB mutant strains. Threonine auxotrophy is observed only in Pseudomonas aeruginosa when both thrB and thrH are simultaneously activated. Overexpression of the new gene also allows complementation of serine auxotrophy of Escherichia coli and Pseudomonas aeruginosa serB strains. In addition, sequence homology is observed between thrH and the serB proteins from different organisms.

Byline: Radia Lamghari El Kossori (1), Christian Villaume (1), Essadiq El Boustani (2), Yves Sauvaire (3), Luc Mejean (1) Keywords: Carbohydrate; Fiber; Minerals; Prickly pear; Protein Abstract: The proximate composition of pulp, skin and seeds of prickly pear cactus (Opuntia ficus indica) was investigated and is reported on a dry weight basis. The most abundant component of the pulp and skin was ethanol-soluble carbohydrates. Pulp contained glucose (35%) and fructose (29%) while the skin contained essentially glucose (21%). Protein content was 5.1% (pulp), 8.3% (skin) and 11.8% (seeds). Starch was found in each of the three parts of the fruit. Pulp fibers were rich in pectin (14.4%), skin and seeds were rich in cellulose (29.1 and 45.1%, respectively). Skin was remarkable for its content of calcium (2.09%) and potassium (3.4%). Prickly pear is a neglected nutritional source which should be more widely used because of its potential nutrient contribution. Author Affiliation: (1) Institut National de la Sante et de la Recherche Medicale (INSERM U308) Equipe de Recherches Aliment et Comportement, 38 rue Lionnois, 54 000, Nancy, France (2) Laboratoire de Biochimie Nutritionnelle et Metabolique, Faculte des Sciences Cadi Ayyad, Marrakech, Maroc (3) Laboratoire de Recherche sur les Substances Naturelles Vegetales, UPR ES 1677, Montpellier, France Article History: Registration Date: 14/10/2004

Industrial veal bone hydrolysate is made enzymatically and its nutritional value is analysed for possible use in human food as gelatin-replacing ingredient. Protein digestibility is about 80.4% and the net protein ratio is about 2.65. The nutritional value is comparable to sodium caseinate. Weight gain and increased diet intake in animals indicate acceptance of veal bone hydrolysate. The hydrolysate contains higher levels of essential amino acids than gelatin and are rich in glycine, hydroxyproline, proline and glutamic acid. It is deficient in tryptophan and isoleucine.

A second reading frame, torT, was isolated and identified as an additional regulator in the Escherichia coli torCAD operon expression. This gene is located downstream from the torR gene. Disruption of the gene by an omega interposon insertion by standard techniques revealed repression of the expression of a torA'-'lacZ fusion. Overproduction of TorR in a torT strain resulted in the partial expression of the torA'-'lacZ fusion, suggesting that torT acts downstream from TorT.

Anaerobiosis and trimethylamine N-oxide (TMAO) induce the expression of the torCAD operon encoding the TMAO reductase system in Escherichia coli. The sequencing and cloning of a torR insertion mutant encodes the 25,000 Dalton protein. The protein exhibits a homology identical to the response regulators of two-component systems. TMAO induction is mediated by the TorR gene, which is located above the torCAD operon.

A novel opioid receptor photoaffinity probe /(super 3)H~naltrexyl urea phenylazido derivative was synthesized and characterized. This compound reversibly binds with high affinity to the mu- and kappa-opioid binding sites and with low affinity to gamma-sites. It also incorporates irreversibly into rat brain and guinea pig cerebellum membranes upon irradiation, photolabeling distinct glycoproteins corresponding to 67 and 58 kDa, respectively, as shown by SDS gel electrophoresis. Therefore, the mu- and kappa-opioid receptors correspond to these distinct glycoproteic entities.

The complete sequence of the gene cluster responsible for the biosynthesis of the cylindrospermopsin, a cytotoxin, in Oscillatoria sp. strain PCC 6506 is described. All the cylindrospermopsin producers have given a PCR product by using specific primers for the amplification of the cryJ gene from genomic DNA.

The in vitro reconstitution of the first steps in the biosynthesis for Oscillatoria PCC 6506 and the identification of the gene coding in PCC 6506 for a Sfp-like phosphopantetheinyl transferase is reported. AnaB which belongs to the acyl-CoA dehydrogenase superfamily might likely be involved in the catalysis of an [alpha]-[beta]-dehydrogenation of the thioester-bound proline followed by an aza-allylic isomerization to yield (S)-pyrroline-5-carboxyl-AnaD, the proposed starter for the subsequent polyketide synthase, AnaE.

The identification of a sequence from the genome of Oscillatoria sp. strain PCC 6506 coding for a polyketide synthase is described. Axenic cyanobacteria is used to show this sequence only in the genomes of Oscillatoria strains producing anatoxin-a or homoanatoxin-a, which has indicated its likely environment in the biosynthesis of these toxins.

Anatoxin-a and homoanatoxin-a are potent neurotoxins that are produced by cyanobacteria and the GC-MS and NMR analyses using labeled precursors have confirmed that proline might be the starter of these polyketide synthases. The data have provided evidence that the studies have identified the gene cluster responsible for the production of anatoxin-a and homoanatoxin-a in Oscillatoria PCC 6506.

Periodic density functional theory calculations were used to compute the third-order hypersusceptibilities of crystalline [alpha]-Te[O.sub.2] and [alpha]-Si[O.sub.2]. The values calculated for [alpha]-Te[O.sub.2] was found to be of same order as measured for Te[O.sub.2] glass and much higher than the values computed for [alpha]-Si[O.sub.2], which were close to that of glassy silica.

Cyanobacterial neurotoxic alkaloid anatoxin is detected in the extracts of water samples from the shores of the Tarn River in southern France. Benthic neurotoxic cyanobacteria are the likely cause for the dog deaths at the river.

Byline: L. Soulhac, P. Mejean, R.J. Perkins The transport and dispersion of pollutants in a street canyon, and the intersection between two streets, have been studied using wind-tunnel experiments and numerical simulations. The study of the street canyon demonstrates the importance of the geometry of the canyon (aspect ratio, asymmetry) in determining both the topology of the flow and the concentration distribution; the flow is also very sensitive to wind direction. The study of the street intersection shows how the intersection influences the flow and dispersion in the adjoining streets. This work has been used to develop new and practical models for flow and dispersion in city streets; these models are compared here with the results from wind-tunnel experiments and numerical simulations.

Research shows that insertion of an ISSo2 element into torA, torR, and torS genes causes mutation in the ability of Shewanella oneidensis using trimethylamine oxide for respiration. Data indicate that the TorS-TorR protein pair photorelay catalyzes trimethylamine oxidase induction. TorA is the main respiratory trimethylamine oxide reductase.

Research has been conducted on the ability of bacteria to reduce selenate and selenite into less toxic elemental selenium. The mechanisms of the reduction and transport of selenium oxyanions in Escherichia coli have been investigated via the use of genetic analysis and transposon mutagenesis, and the results are reported.

Trimethylamine N-oxide (TMAO) respiration is carried out mainly by the Tor system in Escherichia coli. This system is encoded by the torCAD operon and comprises a periplasmic TMAO reductase (TorA) and a c-type cytochrome (TorC), which shuttles electrons to TorA. Expression of the tor operon is positively controlled by the TorS/TorR phosphorelay system in response to TMAO availability and negatively regulated by apocytochrome TorC. Interaction studies showed that, when immature, TorC can no longer bind TorA efficiently but can bind the periplasmic detector region of sensor TorS. ApoTorC negative autoregulation and TMAO induction are thus mediated by the same sensor protein. As apocytochromes related to TorC could not down-regulate the tor operon, we concluded that this negative control is highly specific. Moreover, the N-terminal half of apoTorC played no role in this control but the immature C-terminal domain of TorC strongly down-regulated the tor operon and interacted with the TorS detector region. This sophisticated autoregulatory pathway thus involves the C-terminal domain of apoTorC and allows optimal TorC biogenesis by preventing from saturation the c-type cytochrome maturation machinery.