Substance use during pregnancy and personality dimensions.

Our aim was to assess personality traits associated with substance use during pregnancy in a population-based, multicentre study of 1804 pregnant women. On day 2-3 postpartum, participants completed a semi-structured interview, including self-reported drug use (alcohol, tobacco, caffeine, cannabis, cocaine, opioids) during pregnancy, and socio-demographic, reproductive and obstetric variables, personal and family psychiatric history, social support, and the Eysenck personality questionnaire, short version (EPQ-RS). Logistic regression models were conducted.

The Challenges of Monoaxial Bone Transport in Orthopedics and Traumatology.

Background: Bone defects represent the main challenging problem for the orthopedic surgeon and, consequently, they increase the duration of hospitalization, risk of complications and health expenditures. The aim of our observational, descriptive and retrospective study is to evaluate the outcomes of patients treated with a mo-nolateral external fixator for bone defects greater than 3 cm.

Material And Methods: Between January 2003 and January 2013, 21 patients were treated at our center by bone transfer with a monolateral external fixator.

Relative Termination via Dependency Pairs.

A term rewrite system is terminating when no infinite reduction sequences are possible. Relative termination generalizes termination by permitting infinite reductions as long as some distinguished rules are not applied infinitely many times. Relative termination is thus a fundamental notion that has been used in a number of different contexts, like analyzing the confluence of rewrite systems or the termination of narrowing.

Regulation of bacterial physiology by lysine acetylation of proteins.

Post-translational modification of proteins is a reversible mechanism of cellular adaptation to changing environmental conditions. In eukaryotes, the physiological relevance of N-ɛ-lysine protein acetylation is well demonstrated. In recent times, important roles in the regulation of metabolic processes in bacteria are being uncovered, adding complexity to cellular regulatory networks.

Metabolic engineering for high yielding L(-)-carnitine production in Escherichia coli.

Background: L(-)-carnitine production has been widely studied because of its beneficial properties on various diseases and dysfunctions. Enterobacteria possess a specific biotransformation pathway which can be used for the enantioselective production of L(-)-carnitine. Although bioprocesses catalyzed by enzymes or whole cells can overcome the lack of enantioselectivity of chemical methods, current processes for L(-)-carnitine production still have severe disadvantages, such as the low yields, side reactions and the need of high catalyst concentrations and anaerobic conditions for proper expression of the biotransformation pathway.

Role of central metabolism in the osmoadaptation of the halophilic bacterium Chromohalobacter salexigens.

Bacterial osmoadaptation involves the cytoplasmic accumulation of compatible solutes to counteract extracellular osmolarity. The halophilic and highly halotolerant bacterium Chromohalobacter salexigens is able to grow up to 3 m NaCl in a minimal medium due to the de novo synthesis of ectoines. This is an osmoregulated pathway that burdens central metabolic routes by quantitatively drawing off TCA cycle intermediaries.

EasyLCMS: an asynchronous web application for the automated quantification of LC-MS data.

Background: Downstream applications in metabolomics, as well as mathematical modelling, require data in a quantitative format, which may also necessitate the automated and simultaneous quantification of numerous metabolites. Although numerous applications have been previously developed for metabolomics data handling, automated calibration and calculation of the concentrations in terms of μmol have not been carried out. Moreover, most of the metabolomics applications are designed for GC-MS, and would not be suitable for LC-MS, since in LC, the deviation in the retention time is not linear, which is not taken into account in these applications.

cAMP-CRP co-ordinates the expression of the protein acetylation pathway with central metabolism in Escherichia coli.

Lysine acetylation is a well-established post-translational modification widely conserved and distributed in bacteria. Although multiple regulatory roles have been proved, little is known about its regulation. Here, we present evidence that the transcription of the Gcn5-like acetyltransferase YfiQ of Escherichia coli (proposed name: PatZ) is regulated by cAMP-CRP and its implications on acetate metabolism regulation.

Acetate scavenging activity in Escherichia coli: interplay of acetyl-CoA synthetase and the PEP-glyoxylate cycle in chemostat cultures.

Impairment of acetate production in Escherichia coli is crucial for the performance of many biotechnological processes. Aerobic production of acetate (or acetate overflow) results from changes in the expression of central metabolism genes. Acetyl-CoA synthetase scavenges extracellular acetate in glucose-limited cultures.

A recyclable enzymatic biodiesel production process in ionic liquids.

Immobilized Candida antarctica lipase B suspended in ionic liquids containing long alkyl-chain cations showed excellent synthetic activity and operational stability for biodiesel production. The interest of this process lies in the possibility of recycling the biocatalyst and the easy separation of the biodiesel from the reaction mixture. The ionic liquids used, 1-hexadecyl-3-methylimidazolium triflimide ([C(16)MIM][NTf(2)]) and 1-octadecyl-3-methylimidazolium triflimide ([C(18)MIM][NTf(2)]), produced homogeneous systems at the start of the reaction and, at the end of the same, formed a three-phase system, allowing the selective extraction of the products using straightforward separation techniques, and the recycling of both the ionic liquid and the enzyme.

Ectoines in cell stress protection: uses and biotechnological production.

Microorganisms produce and accumulate compatible solutes aiming at protecting themselves from environmental stresses. Among them, the wide spread in nature ectoines are receiving increasing attention by the scientific community because of their multiple applications. In fact, increasing commercial demand has led to a multiplication of efforts in order to improve processes for their production.

An insight into the role of phosphotransacetylase (pta) and the acetate/acetyl-CoA node in Escherichia coli.

Background: Acetate metabolism in Escherichia coli plays an important role in the control of the central metabolism and in bioprocess performance. The main problems related to the use of E. coli as cellular factory are i) the deficient utilization of carbon source due to the excretion of acetate during aerobic growth, ii) the inhibition of cellular growth and protein production by acetate and iii) the need for cofactor recycling (namely redox coenzymes and free CoASH) to sustain balanced growth and cellular homeostasis.

On the nature of ionic liquids and their effects on lipases that catalyze ester synthesis.

Free and immobilized lipases from Candida antarctica (CALA and CALB), Thermomyces lanuginosus (TLL) and Rhizomucor miehei (RML) were used as catalysts in the synthesis of butyl propionate by transesterification in reaction media consisting in nine different ionic liquids. Enzyme activities were clearly dependent on the nature of the ions, the results being improving as the alkyl chain length of the imidazolium cation increased, and as a function of the type of anion ([PF(6)], [BF(4)] or [ethylsulphate]). The best synthetic activity (655.

Role of betaine:CoA ligase (CaiC) in the activation of betaines and the transfer of coenzyme A in Escherichia coli.

Aims: Characterization of the role of CaiC in the biotransformation of trimethylammonium compounds into l(-)-carnitine in Escherichia coli.

Methods And Results: The caiC gene was cloned and overexpressed in E. coli and its effect on the production of l(-)-carnitine was analysed.

Impairing and monitoring glucose catabolite repression in L-carnitine biosynthesis.

Signal transduction pathways are usually avoided when optimizing a biotransformation process because they require complex mathematical formulations. The aim of this work was to use a Systems Biology approach to optimize and monitor the biotransformation of L-carnitine using signal transduction pathways. To this end, a dynamic model was constructed, integrating the metabolic pathways of L-carnitine biosynthesis as well as the expression of this metabolism by means of its regulation by transcription factors such as cAMP-CRP and CaiF.

Production of L-carnitine by secondary metabolism of bacteria.

The increasing commercial demand for L-carnitine has led to a multiplication of efforts to improve its production with bacteria. The use of different cell environments, such as growing, resting, permeabilized, dried, osmotically stressed, freely suspended and immobilized cells, to maintain enzymes sufficiently active for L-carnitine production is discussed in the text. The different cell states of enterobacteria, such as Escherichia coli and Proteus sp.

Role of wet experiment design in data generation: from in vivo to in silico and back.

A thorough understanding of the in vivo kinetics of microorganisms requires the analysis of different data sets and therefore needs support from different sources of genome, transcriptome, proteome and metabolome data, as well as to generate new data in the laboratory to depict cell phenotypes in different scenarios. The value of dynamic metabolic data depends on the adequate design of wet experiments. In this paper a schematic representation of wet dynamic experiments to generate data is discussed.

Redirecting metabolic fluxes through cofactor engineering: Role of CoA-esters pool during L(-)-carnitine production by Escherichia coli.

Cofactor engineering, defined as the purposeful modification of the pool of intracellular cofactors, has been demonstrated to be a very suitable strategy for the improvement of L(-)-carnitine production in Escherichia coli strains. The overexpression of CaiB (CoA-transferase) and CaiC (CoA-ligase), both enzymes involved in coenzyme A transfer and substrate activation during the bioprocess, led to an increase in L(-)-carnitine production. Under optimal concentrations of inducer and fumarate (used as electron acceptors) yields reached 10- and 50-fold, respectively, that obtained for the wild type strain.

Plasmid maintenance and physiology of a genetically engineered Escherichia coli strain during continuous L-carnitine production.

The effect of immobilization on cell physiology and how this determines cell metabolic performance is an important concern for developing bioprocess. This is particularly true for genetically modified microorganisms and their genetic stability. For this reason the stability and physiological state of plasmid-bearing E.

Role of energetic coenzyme pools in the production of L-carnitine by Escherichia coli.

The aim of this work was to understand the steps controlling the biotransformation of trimethylammonium compounds into L(-)-carnitine by Escherichia coli. The high-cell density reactor steady-state levels of carbon source (glycerol), biotransformation substrate (crotonobetaine), acetate (anaerobiosis product) and fumarate (as an electron acceptor) were pulsed by increasing them fivefold. Following the pulse, the evolution of the enzyme activities involved in the biotransformation process of crotonobetaine into L(-)-carnitine (crotonobetaine hydration), in the synthesis of acetyl-CoA (ACS: acetyl-CoA synthetase and PTA: ATP: acetate phosphotransferase) and in the distribution of metabolites for the tricarboxylic acid (ICDH: isocitrate dehydrogenase) and glyoxylate (ICL: isocitrate lyase) cycles was monitored.

Chemoenzymatic dynamic kinetic resolution of rac-1-phenylethanol in ionic liquids and ionic liquids/supercritical carbon dioxide systems.

Continuous dynamic kinetic resolution processes in different ionic liquid/supercritical carbon dioxide biphasic systems were carried out by simultaneously using both immobilized Candida antarctica lipase B (Novozym 435) and silica modified with benzenosulfonic acid (SCX) catalysts at 40 degrees C and 10 MPa. SCX was seen to act as an efficient heterogeneous chemical catalyst for the racemization of (S)-1-phenylethanol in different ionic liquid media ([emim][NTf(2)], [btma][NTf(2)] and [bmim][PF(6)]). Coating both chemical and enzymatic catalysts with ILs greatly improved the efficiency of the process, providing a good yield (76%) of (R)-1-phenylethyl propionate product with excellent enantioselectivity (ee = 91-98%) in continuous operation.

Salt stress effects on the central and carnitine metabolisms of Escherichia coli.

The aim was to understand how interaction of the central carbon and the secondary carnitine metabolisms is affected under salt stress and its effect on the production of L-carnitine by Escherichia coli. The biotransformation of crotonobetaine into L-carnitine by resting cells of E. coli O44 K74 was improved by salt stress, a yield of nearly twofold that for the control being obtained with 0.

Model of central and trimethylammonium metabolism for optimizing L-carnitine production by E. coli.

The application of metabolic engineering principles to the rational design of microbial production processes crucially depends on the ability to make quantitative descriptions of the systemic ability of the central carbon metabolism to redirect fluxes to the product-forming pathways. The aim of this work was to further our understanding of the steps controlling the biotransformation of trimethylammonium compounds into L-carnitine by Escherichia coli. Despite the importance of L-carnitine production processes, development of a model of the central carbon metabolism linked to the secondary carnitine metabolism of E.

Understanding structure-stability relationships of Candida antartica lipase B in ionic liquids.

Two different water-immiscible ionic liquids (ILs), 1-ethyl-3-methylimidizolium bis(trifluoromethylsulfonyl)imide and butyltrimethylammonium bis(trifluoromethylsulfonyl)imide, were used for butyl butyrate synthesis from vinyl butyrate catalyzed by Candida antarctica lipase B (CALB) at 2% (v/v) water content and 50 degrees C. Both the synthetic activity and stability of the enzyme in these ILs were enhanced as compared to those in hexane. Circular dichroism and intrinsic fluorescence spectroscopic techniques have been used over a period of 4 days to determine structural changes in the enzyme associated with differences in its stability for each assayed medium.