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Introduction: Mortality in emergency departments (EDs) is not well known. This study aimed to assess the impact of the first-wave pandemic on deaths accounted in the ED of older patients with COVID and non-COVID diseases. Methods: We used data from the Emergency Department and Elderly Needs (EDEN) cohort (pre-COVID period) and from the EDEN-COVID cohort (COVID period) that included all patients ≥65 years seen in 52 Spanish EDs from April 1 to 7, 2019, and March 30 to April 5, 2020, respectively. We recorded patient characteristics and final destination at ED. We compared older patients in the pre-COVID period, with older patients with non-COVID and with COVID-19. ED-mortality (before discharge or hospitalization) is the prior outcome and is expressed as an adjusted odds ratio (aOR) with 95% interval confidence. Results: We included 23,338 older patients from the pre-COVID period (aged 78.3 [8.1] years), 6,715 patients with non-COVID conditions (aged 78.9 [8.2] years) and 3,055 with COVID (aged 78.3 [8.3] years) from the COVID period. Compared to the older patients, pre-COVID period, patients with non-COVID and with COVID-19 were more often male, referred by a doctor and by ambulance, with more comorbidity and disability, dementia, nursing home, and more risk according to qSOFA, respectively (p < 0.001). Compared to the pre-COVID period, patients with non-COVID and with COVID-19 were more often to be hospitalized from ED (24.8% vs. 44.3% vs. 79.1%) and were more often to die in ED (0.6% vs. 1.2% vs. 2.2%), respectively (p < 0.001). Compared to the pre-COVID period, aOR for age, sex, comorbidity and disability, ED mortality in elderly patients cared in ED during the COVID period was 2.31 (95% confidence interval [CI]: 1.76–3.06), and 3.75 (95% CI: 2.77–5.07) for patients with COVID. By adding the variable qSOFA to the model, such OR were 1.59 (95% CI: 1.11–2.30) and 2.16 (95% CI: 1.47–3.17), respectively. Conclusions: During the early first pandemic wave of COVID-19, more complex and life-threatening older with COVID and non-COVID diseases were seen compared to the pre-COVID period. In addition, the need for hospitalization and the ED mortality doubled in non-COVID and tripled in COVID diagnosis. This increase in ED mortality is not only explained by the complexity or severity of the elderly patients but also because of the system's overload. [ABSTRACT FROM AUTHOR]

AbstractObjectivesMethodResultsConclusionTo assess whether dementia is an independent predictor of death after a hospital emergency department (ED) visit by older adults with or without a COVID-19 diagnosis during the first pandemic wave.We used data from the EDEN-Covid (Emergency Department and Elderly Needs during Covid) cohort formed by all patients ≥65 years seen in 52 Spanish EDs from March 30 to April 5, 2020. The association of prior history of dementia with mortality at 30, 180 and 365 d was evaluated in the overall sample and according to a COVID-19 or non COVID diagnosis.We included 9,770 patients aged 78.7 ± 8.3 years, 51.1% men, 1513 (15.5%) subjects with prior history of dementia and 3055 (31.3%) with COVID-19 diagnosis. 1399 patients (14.3%) died at 30 d, 2008 (20.6%) at 180 days and 2456 (25.1%) at 365 d. The adjusted Hazard Ratio (aHR) for age, sex, comorbidity, disability and diagnosis for death associated with dementia were 1.16 (95% CI 1.01–1.34) at 30 d; 1.15 at 180 d (95% CI 1.03–1.30) and 1.19 at 365 d (95% CI 1.07–1.32), p < .001. In patients with COVID-19, the aHR were 1.26 (95% CI: 1.04–1.52) at 30 days; 1.29 at 180 d (95% CI: 1.09–1.53) and 1.35 at 365 d (95% CI: 1.15–1.58).Dementia in older adults attending Spanish EDs during the first pandemic wave was independently associated with 30-, 180- and 365-day mortality. This impact was lower when adjusted for age, sex, comorbidity and disability, and was greater in patients diagnosed with COVID-19. [ABSTRACT FROM AUTHOR]

Background: The eruption of the Tajogaite volcano began on the island of La Palma on September 19, 2021, lasting for 85 days. This study aims to present the design and methodology of the ISVOLCAN (Health Impact on the Population of La Palma due to the Volcanic Eruption) cohort, as well as the preliminary findings from the first 1002 enrolled participants. Methods: A prospective cohort study was conducted with random selection of adult participants from the general population, with an estimated sample size of 2600 individuals. The results of the first 857 participants are presented, along with a group of 145 voluntary participants who served as interveners during the eruption. Data on epidemiology and volcano exposure were collected, and participants underwent physical examinations, including anthropometry, blood pressure measurement, spirometry, and venous blood extraction for toxicological assessment. Results: In the general population (n = 857), descriptive analysis revealed that the participants were mostly middle-aged individuals (50.8 ± 16.4), with a predominance of females. Before the eruption, the participants resided at a median distance of 6.7 km from the volcano in the Western region and 10.9 km in the Eastern region. Approximately 15.4% of the sample required evacuation, whose 34.8% returning to their homes on average after 3 months. A significant number of participants reported engaging in daily tasks involving cleaning of volcanic ash both indoors and outdoors. The most reported acute symptoms included ocular irritation, insomnia, mood disorders (anxiety-depression), and respiratory symptoms. Multivariate analysis results show that participants in the western region had a higher likelihood of lower respiratory tract symptoms (OR 1.99; 95% CI:1.33–2.99), depression and anxiety (OR 1.95; 95% CI:1.30–2.93), and insomnia (OR 2.03; 95% CI:1.33–3.09), compared to those in the eastern region. Conclusion: The ongoing follow-up of the ISVOLCAN cohort will provide valuable insights into the short, medium, and long-term health impact related to the material emitted during the Tajogaite eruption, based on the level of exposure suffered by the affected population. [ABSTRACT FROM AUTHOR]

Biobased polymers derived from plant oils are sustainable alternatives to petro based polymers. In recent years, multienzyme cascades have been developed for the synthesis of biobased ω-aminocarboxylic acids, which serve as building blocks for polyamides. In this work, we have developed a novel enzyme cascade for the synthesis of 12-aminododeceneoic acid, a precursor for nylon-12, starting from linoleic acid. Seven bacterial ω-transaminases (ω-TAs) were cloned, expressed in Escherichia coli and successfully purified by affinity chromatography. Activity towards the oxylipin pathway intermediates hexanal and 12-oxododecenoic acid in their 9(Z) and 10(E) isoforms was demonstrated for all seven transaminases in a coupled photometric enzyme assay. The highest specific activities were obtained with ω-TA from Aquitalea denitrificans (TRAD), with 0.62 U mg−1 for 12-oxo-9(Z)-dodecenoic acid, 0.52 U mg−1 for 12-oxo-10(E)-dodecenoic acid and 1.17 U mg−1 for hexanal. A one-pot enzyme cascade was established with TRAD and papaya hydroperoxide lyase (HPLCP-N), reaching conversions of 59% according to LC-ELSD quantification. Starting from linoleic acid, up to 12% conversion to 12-aminododecenoic acid was achieved with a 3-enzyme cascade comprising soybean lipoxygenase (LOX-1), HPLCP-N and TRAD. Higher product concentrations were achieved by the consecutive addition of enzymes compared to simultaneous addition at the beginning. Key points: • Seven ω-transaminases converted 12-oxododecenoic acid into its corresponding amine. • A three-enzyme cascade with lipoxygenase, hydroperoxide lyase, and ω-transaminase was established for the first time. • A one-pot transformation of linoleic acid to 12-aminododecenoic acid, a precursor of nylon-12 was achieved. [ABSTRACT FROM AUTHOR]

This study described the clinical, virological, and serological responses of immunologically naïve and vaccinated horses to African horse sickness virus (AHSV) serotype 9. Naïve horses developed a clinical picture resembling the cardiac form of African horse sickness. This was characterized by inappetence, reduced activity, and hyperthermia leading to lethargy and immobility–recumbency by days 9–10 post-infection, an end-point criteria for euthanasia. After challenge, unvaccinated horses were viremic from days 3 or 4 post-infection till euthanasia, as detected by serogroup-specific (GS) real time RT-PCR (rRT-PCR) and virus isolation. Virus isolation, antigen ELISA, and GS-rRT-PCR also demonstrated high sensitivity in the post-mortem detection of the pathogen. After infection, serogroup-specific VP7 antibodies were undetectable by blocking ELISA (b-ELISA) in 2 out of 3 unvaccinated horses during the course of the disease (9–10 dpi). Vaccinated horses did not show significant side effects post-vaccination and were largely asymptomatic after the AHSV-9 challenge. VP7-specific antibodies could not be detected by the b-ELISA until day 21 and day 30 post-inoculation, respectively. Virus neutralizing antibody titres were low or even undetectable for specific serotypes in the vaccinated horses. Virus isolation and GS-rRT-PCR detected the presence of AHSV vaccine strains genomes and infectious vaccine virus after vaccination and challenge. This study established an experimental infection model of AHSV-9 in horses and characterized the main clinical, virological, and immunological parameters in both immunologically naïve and vaccinated horses using standardized bio-assays. [ABSTRACT FROM AUTHOR]

The aim of the present study is to describe the behavioral and emotional disturbances in the Fragile X Syndrome (FXS) and to analize the impact of having a member with FXS on different aspects of family functioning. A sample of 79 parents with a member with FXS and 80 parents with a member with typical development participated in the study. Results showed that between 17% and 66% of children and adolescents with FXS displayed significant behavioral and emotional disturbances and fewer prosocial behaviors. In addition, after controlling for behavioral and emotional difficulties, our results showed that families affected by FXS experienced a more negative impact on feelings about parenting, finances, siblings, and the degree of difficulty of living with a child or adolescent with FXS, and greater family adaptability and cohesion than the comparison group. In conclusion, our results highlight that it is important to consider these differences in clinical practice when supporting and counselling families affected by FXS. [ABSTRACT FROM AUTHOR]

Background: Previous literature highlights the importance of causal attributions in achievement and motivation. However, the studies about causal attributions in second language acquisition (SLA) are limited and scarce. Aims: This study was designed to determine the frequency of successful and unsuccessful activities per English level and to compare the causal attributions (explanations of outcomes) on successful and failure authentic tasks undertaken in the context of learning English as a foreign language (EFL) acquisition in an Official School of Languages (OSL). Sample: To this aim, 407 native Spanish students from levels A1 (n = 111), A2 (n = 113), B1 (n = 98), and B2 (n = 85) in OSL participated in this study. Method: Participants completed Attribution to Success and Failure Questionnaires (ASQ & AFQ). Results: Results of ANOVAs and Scheffe post hoc test show main significant differences between A1 and B2 students. Students at A1 level perceive their success in the foreign language (FL) as dependent on some internal but unstable controllable variables, such as effort and strategy, and to some external variables such as teacher influence, task difficulty, and class atmosphere. On the contrary, students at B2 level perceive that their successful outcomes in FL depend on ability, marks, class level, preparation, and enjoyment within the classroom, whereas they perceive that their failure outcomes are dependent on external factors such as luck, teacher influence, and/or task difficulty. Conclusions: Results provide evidence that students from OSL employ multiple causal attributions to explain their academic success and failure, which may also have educational implications for class teachers. [ABSTRACT FROM AUTHOR]

Studies that have compared the knowledge that pre-service teachers (PSE) and in-service teachers (PCE) have about ADHD have shown conflicting results. In addition, the role that teaching experience with children with ADHD has on knowledge, self-efficacy and teacher stress has not been addressed in previous studies. Therefore, this study aims to: a) compare the knowledge, misconceptions and knowledge gaps of the PCE and PSE of Spain, about ADHD; b) analyze the experience of PCE with children with ADHD and the relationship with knowledge, self-efficacy, and teacher stress; c) analyze the relations of knowledge about ADHD with sociodemographic variables. 134 PSE and 115 PCE participated. They completed the Knowledge Scale on Attention Deficit Hyperactivity Disorder (KADDS), the Teaching Stress Index (STI) and a socio-demographic information questionnaire. The results indicate that the knowledge of both groups is similar, although the PSE obtained more successes on symptoms / diagnosis and the PCE presented more misconceptions on the total scale and on symptoms / diagnosis. The PCE, who had experience with children with ADHD, experienced a higher level of teacher stress and greater self-efficacy. Knowledge about ADHD correlated with career subjects, courses on ADHD and years of professional experience. [ABSTRACT FROM AUTHOR]

The article provides an overview of discourse of mass communications in Venezuela. It mentions change to the discursive practices of television and marketing firms. It also mentions cause of Audience migration which include public rejection of the politicization of television and of the conflictive nature of the content broadcast on terrestrial networks, and economic restrictions placed on private television companies that affected their investment potential.

The laboratory diagnosis of African horse sickness (AHS) is important for: (a) demonstrating freedom from infection in a population, animals or products for trade (b) assessing the efficiency of eradication policies; (c) laboratory confirmation of clinical diagnosis; (d) estimating the prevalence of AHS infection; and (e) assessing postvaccination immune status of individual animals or populations. Although serological techniques play a secondary role in the confirmation of clinical cases, their use is very important for all the other purposes due to their high throughput, ease of use and good cost‐benefit ratio. The main objective of this study was to support the validation of AHS VP7 Blocking ELISA up to the Stage 3 of the World Animal Health Organization (OIE) assay validation pathway. To achieve this, a collaborative ring trial, which included all OIE Reference Laboratories and other AHS‐specialist diagnostic centres, was conducted in order to assess the diagnostic performance characteristics of the VP7 Blocking ELISA. In this trial, a panel of sera of different epidemiological origin and infection status was used. Through this comprehensive evaluation we can conclude that the VP7 Blocking ELISA satisfies the OIE requirements of reproducibility. The VP7 Blocking ELISA, in its commercial version is ready to enter Stage 4 of the validation pathway (Programme Implementation). Specifically, this will require testing the diagnostic performance of the assay using contemporary serum samples collected during control campaigns in endemic countries. [ABSTRACT FROM AUTHOR]

The recently discovered Methanonatronarchaeia are extremely halophilic and moderately thermophilic methyl-reducing methanogens representing a novel class-level lineage in the phylum Euryarchaeota related to the class Halobacteria. Here we present a detailed analysis of 1D-nano liquid chromatography-electrospray ionization tandem mass spectrometry data obtained for "Methanonatronarchaeum thermophilum" AMET1 grown in different physiological conditions, including variation of the growth temperature and substrates. Analysis of these data allows us to refine the current understanding of the key biosynthetic pathways of this triple extremophilic methanogenic euryarchaeon and identify proteins that are likely to be involved in its response to growth condition changes. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the knowledge, misconceptions, and knowledge gaps of Peruvian pre-service teachers (PSTs) and in-service teachers (ISTs). To do so, 112 PSTs and 113 ISTs completed the Knowledge and Beliefs About Developmental Dyslexia Scale (KBDDS). Results show that ISTs scored significantly higher than PSTs. Moreover, misconceptions and lack of information were higher in PSTs. The most noteworthy misconceptions were that dyslexia is due to poor visual perception and that letter or word reversals are the most important criterion in the identification of dyslexia. Age, years of teaching experience, prior exposure to a child with dyslexia, and self-efficacy were positively correlated with knowledge about dyslexia in ISTs. [ABSTRACT FROM AUTHOR]

Our microbiome should be understood as one of the most complex components of the human body. The use of β-lactam antibiotics is one of the microbiome covariates that influence its composition. The extent to which our microbiota changes after an antibiotic intervention depends not only on the chemical nature of the antibiotic or cocktail of antibiotics used to treat specific infections, but also on the type of administration, duration and dose, as well as the level of resistance that each microbiota develops. We have begun to appreciate that not all bacteria within our microbiota are vulnerable or reactive to different antibiotic interventions, and that their influence on both microbial composition and metabolism may differ. Antibiotics are being used worldwide on a huge scale and the prescription of antibiotics is continuing to rise; however, their effects on our microbiota have been reported for only a limited number of them. This article presents a critical review of the antibiotics or antibiotic cocktails whose use in humans has been linked to changes in the composition of our microbial communities, with a particular focus on the gut, oral, respiratory, skin and vaginal microbiota, and on their molecular agents (genes, proteins and metabolites). We review the state of the art as of June 2016, and cover a total of circa 68 different antibiotics. The data herein are the first to compile information about the bacteria, fungi, archaea and viruses most influenced by the main antibiotic treatments prescribed nowadays. [ABSTRACT FROM AUTHOR]

The microbiota should be considered as just another component of the human epigenetic landscape. Thus, health is also a reflection of the diversity and composition of gut microbiota and its metabolic status. In defining host health, it remains unclear whether diversity is paramount, or whether greater weight is held by gut microbiota composition or mono- or multiple-functional capacity of the different taxa and the mechanisms involved. A network-biology approach may shed light on the key gut players acting to protect against, or promote, disorders or diseases. This could be achieved by integrating data on total and active species, proteins and molecules, and their association with host response. In this review, we discuss the utilization of top-down and bottom-up approaches, following a functional hierarchy perspective. [ABSTRACT FROM AUTHOR]

The present study investigated knowledge, misconceptions, and lack of information about dyslexia among pre-service (PST) and in-service (IST) Spanish-speaking teachers in Spain and Peru. Two hundred and forty-six pre-service teachers and 267 in-service teachers completed the Knowledge and Beliefs about Developmental Dyslexia Scale (KBDDS). In-service teachers scored significantly higher on the total scale, and on the symptoms/diagnosis and general information subscales, than pre-service teachers. The percentages for misconceptions and lack of information ("do not know responses") were higher for PSTs than for ISTs on the general information subscale, the symptoms/diagnosis subscale, and the treatment subscale. Analyses of individual items were conducted to differentiate concepts that teachers did not know from misconceptions. In-service teacher self-efficacy, years of teaching experience, post-graduate training in dyslexia, and prior exposure to a child with dyslexia were positively related to knowledge about dyslexia. Implications for pre-service teacher training and professional development are discussed. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the reaction times and errors of Spanish children with developmental dyslexia to the reaction times and errors of readers without dyslexia on a masked lexical decision task with identity or repetition priming. A priming paradigm was used to study the role of the lexical deficit in dyslexic children, manipulating the frequency and length of the words, with a short Stimulus Onset Asynchrony (SOA = 150 ms) and degraded stimuli. The sample consisted of 80 participants from 9 to 14 years old, divided equally into a group with a developmental dyslexia diagnosis and a control group without dyslexia. Results show that identity priming is higher in control children (133 ms) than in dyslexic children (55 ms). Thus, the “frequency” and “word length” variables are not the source or origin of this reduction in identity priming reaction times in children with developmental dyslexia compared to control children. [ABSTRACT FROM PUBLISHER]

Dyslexia in adulthood affects around 4% of the population. Thus, this study offers an overview of the methodological aspects and the areas of research in dyslexia in adulthood. From a bibliographical search conducted in the Psychological Abstracts database: PsycINFO, we identified and selected the studies the review was to focus on. Results show in relation to methodological aspects, quantitative research methods are preferred in 59.4% of cases, whereas 5.7% opted for qualitative methods. Also, in 10% of the studies, used N=1 designs and in an under 10% studies used surveys, longitudinal/ follow-up studies or neurobiological procedures. In relation to the topics of research, 40.6% analyzed cognitive processes (phonemic awareness, memory, IQ, naming speed) and/or academic achievement (word reading, pseudoword reading, spelling, and reading comprehension), the 25.4% we-re neurobiological studies (neurological and genetics), the 12% were studies focusing on intervention, the 8% focused on identification/ diagnostic, and 5.4% analyzed associated problems to dyslexia in adulthood. The primary objectives of the research appear to be the characterisation of dyslexia and studies about neurobiological basis of dyslexia in adulthood. Research is also extended towards other, more practical matters. [ABSTRACT FROM AUTHOR]

Recent reports have suggested that the establishment of industrially relevant enzyme collections from environmental genomes has become a routine procedure. Across the studies assessed, a mean number of approximately 44 active clones were obtained in an average size of approximately 53 000 clones tested using naïve screening protocols. This number could be significantly increased in shorter times when novel metagenome enzyme sequences obtained by direct sequencing are selected and subjected to high-throughput expression for subsequent production and characterization. The pre-screening of clone libraries by naïve screens followed by the pyrosequencing of the inserts allowed for a 106-fold increase in the success rate of identifying genes encoding enzymes of interest. However, a much longer time, usually on the order of years, is needed from the time of enzyme identification to the establishment of an industrial process. If the hit frequency for the identification of enzymes performing at high turnover rates under real application conditions could be increased while still covering a high natural diversity, the very expensive and time-consuming enzyme optimization phase would likely be significantly shortened. At this point, it is important to review the current knowledge about the success of fine-tuned naïve- and sequence-based screening protocols for enzyme selection and to describe the environments worldwide that have already been subjected to enzyme screen programmes through metagenomic tools. Here, we provide such estimations and suggest the current challenges and future actions needed before environmental enzymes can be successfully introduced into the market. [ABSTRACT FROM AUTHOR]

Natural biodiversity undoubtedly inspires biocatalysis research and innovation. Biotransformations of interest also inspire the search for appropriate biocatalysts in nature. Indeed, natural genetic resources have been found to support the hydrolysis and synthesis of not only common but also unusual synthetic scaffolds. The emerging tool of metagenomics has the advantage of allowing straightforward identification of activity directly applicable as biocatalysis. However, new enzymes must not only have outstanding properties in terms of performance but also other properties superior to those of well-established commercial preparations in order to successfully replace the latter. Esterases (EST) and lipases (LIP) from the α/β-hydrolase fold superfamily are among the enzymes primarily used in biocatalysis. Accordingly, they have been extensively examined with metagenomics. Here we provided an updated (October 2015) overview of sequence and functional data sets of 288 EST–LIP enzymes with validated functions that have been isolated in metagenomes and (mostly partially) characterized. Through sequence, biochemical, and reactivity analyses, we attempted to understand the phenomenon of variability and versatility within this group of enzymes and to implement this knowledge to identify sequences encoding EST–LIP which may be useful for biocatalysis. We found that the diversity of described EST–LIP polypeptides was not dominated by a particular type of protein or highly similar clusters of proteins but rather by diverse nonredundant sequences. Purified EST–LIP exhibited a wide temperature activity range of 10–85 °C, although a preferred bias for a mesophilic temperature range (35–40 °C) was observed. At least 60% of the total characterized metagenomics-derived EST–LIP showed outstanding properties in terms of stability (solvent tolerance) and reactivity (selectivity and substrate profile), which are the features of interest in biocatalysis. We hope that, in the future, the search for and utilization of sequences similar to those already encoded and characterized EST–LIP enzymes from metagenomes may be of interest for promoting unresolved biotransformations in the chemical industry. Some examples are discussed in this review. [ABSTRACT FROM PUBLISHER]

Background: bariatric surgery is widely employed nowadays. Nutritional complications following malabsorptive bariatric surgery are common.Objectives: to compare protein malnutrition incidence, the amount of protein intake and the influence of various risk factors in patients undergoing Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD).Methods: retrospective study comparing the development of hypoalbuminemia in 92 patients undergoing BPD and 121 RYGB, before surgery and 3, 6, 12, 18 and 24 months after it. Protein intake was estimated by serum prealbumin. The influence of prior body mass index (BMI), age and sex was analyzed.Results: hypoprealbuminemia was found in around 40% of patients 3 months after both procedures, decreasing to about 10% after 2 years of surgery. Hypoalbuminemia incidence was close to 20% in the first post-surgery year in BPD, persisting in 10-15% of cases thereafter. After RYGB, hypoalbuminemia incidence was lower (5-9% in all postoperative follow-up measurements). During the first year after surgery, hypoalbuminemia was more frequent after BPD than after RYGB (at the 3rd month (OR:3.9; p=0.006; 95%CI:1.5-10.4), 6th (OR:5.0; p=0.002; 95% CI:1.8-13.8), and at the 12th month (OR:4.4;p=0.007;95%;CI:1.5-12.8)), but not after the first year. A higher preoperative BMI favored it (OR: 1.03; p=0.046; 95% CI:1-1.06), as well as greater age during the first 6 months.Conclusion: Patients with BPD had a higher risk for hypoproteinemia than those undergoing RYGB, especially during the first year post-surgery. Higher preoperative BMI, and age (in the short-term period) could have a significant inverse relation to hypoproteinemia. [ABSTRACT FROM AUTHOR]

Euryarchaea from the genus H alorhabdus have been found in hypersaline habitats worldwide, yet are represented by only two isolates: H alorhabdus utahensis AX-2T from the shallow Great Salt Lake of Utah, and H alorhabdus tiamatea SARL4 BT from the Shaban deep-sea hypersaline anoxic lake ( DHAL) in the Red Sea. We sequenced the H . tiamatea genome to elucidate its niche adaptations. Among sequenced archaea, H . tiamatea features the highest number of glycoside hydrolases, the majority of which were expressed in proteome experiments. Annotations and glycosidase activity measurements suggested an adaptation towards recalcitrant algal and plant-derived hemicelluloses. Glycosidase activities were higher at 2% than at 0% or 5% oxygen, supporting a preference for low-oxygen conditions. Likewise, proteomics indicated quinone-mediated electron transport at 2% oxygen, but a notable stress response at 5% oxygen. H alorhabdus tiamatea furthermore encodes proteins characteristic for thermophiles and light-dependent enzymes (e.g. bacteriorhodopsin), suggesting that H . tiamatea evolution was mostly not governed by a cold, dark, anoxic deep-sea habitat. Using enrichment and metagenomics, we could demonstrate presence of similar glycoside hydrolase-rich H alorhabdus members in the Mediterranean DHAL Medee, which supports that H alorhabdus species can occupy a distinct niche as polysaccharide degraders in hypersaline environments. [ABSTRACT FROM AUTHOR]

Abstract: Antibody detection is the basis of large-scale sheep brucellosis diagnosis because of its sensitivity and specificity. In contrast, information on the cellular mediated immune (CMI) response triggered after Brucella melitensis infection, a cornerstone in the protection against this pathogen, is more limited, particularly regarding the effect of the virulence of the infecting strain in the induced CMI reaction. Here, the interferon-gamma (IFN-γ) profiles evoked after exposure by different routes to virulent (H38) and attenuated (Rev.1) B. melitensis strains in 14 pregnant sheep and 87 ewe lambs, respectively, were characterized accounting for different host-related factors, and compared with their serological response and with the basal IFN-γ responses observed in 155 animals non exposed to Brucella. No significant differences in the IFN-γ response of Rev.1 vaccinated animals depending on the inoculation route was observed, in contrast with their serological results. Response in H38-challenged followed a similar trend although peaked later, and an effect of the abortion on the IFN-γ response was detected. This information could help to understand the interaction bacteria–host that leads to its intracellular survival and could be useful for the design of new diagnostic approaches. [Copyright &y& Elsevier]

Highlights: [•] Kinetic analysis of CeO2-TiO2 materials in toluene and E. coli photo-elimination. [•] Modelling of chemical and biological degradation processes under UV and Visible light illumination. [•] The Ce-Ti systems outperforms titania (including P25) and ceria single oxide references. [•] The Ce-Ti system shows potential for general application in the elimination of pollutants. [Copyright &y& Elsevier]

The aim of this study was to compare the effects of two grouping formats on the reading comprehension. Reading comprehension Instruction used reciprocal teaching (RT) that is an instructional procedure to teach students cognitive strategies that might lead to improved reading comprehension. A sample of 43 students in the fourth year of primary education was selected: 18 children were instructed in regular classroom (GG), 8 were instructed in small group (PG), while the remaining 17 made up the comparison group (GC). Two types of comprehension measures were used: tasks of specific effects (getting the main idea, comprehension-monitoring test) and transfer effect measures (standardized test, word meaning inference, and free recall). Thus, the results show that both RT conditions benefited from the instruction, performing better than the comparison group in measures of specific effects and in the transfer effect measures. Furthermore, students from small group (PG) outperformed students in GG and GC on specific effects and in the transfer effect measures. [ABSTRACT FROM AUTHOR]

Mediterranean Sea is facing a very high risk of oil pollution due to the high number of oil extractive and refining sites along the basin coasts, and the intense maritime traffic of oil tankers. All the Mediterranean countries have adopted severe regulations for minimizing pollution events and bioremediation feasibility studies for the most urgent polluted sites are undergoing. However, the analysis of the scientific studies applying modern ‘meta-omics’ technologies that have been performed on marine oil pollution worldwide showed that the Southern Mediterranean side has been neglected by the international research. Most of the studies in the Mediterranean Sea have been done in polluted sites of the Northern side of the basin. Those of the Southern side are poorly studied, despite many of the Southern countries being major oil producers and exporters. The recently EU-funded research project ULIXES has as a major objective to increase the knowledge of the bioremediation potential of sites from the Southern Mediterranean countries. ULIXES is targeting four major polluted sites on the coastlines of Egypt, Jordan, Morocco and Tunisia, including seashore sands, lagoons, and oil refinery polluted sediments. The research is designed to unravel, categorize, catalogue, exploit and manage the diversity and ecology of microorganisms thriving in these polluted sites. Isolation of novel hydrocarbon degrading microbes and a series of state of the art ‘meta-omics’ technologies are the baseline tools for improving our knowledge on biodegradation capacities mediated by microbes under different environmental settings and for designing novel site-tailored bioremediation approaches. A network of twelve European and Southern Mediterranean partners is cooperating for plugging the existing gap of knowledge for the development of novel bioremediation processes targeting such poorly investigated polluted sites. [ABSTRACT FROM AUTHOR]

Attention-deficit/hyperactivity disorder (ADHD) is frequently associated with learning disabilities. The present study examined the written composition of children with ADHD, which depends to a large degree on continuous self-regulation and attentional control skills for organizing information and maintaining the level of effort. Fifty children with ADHD and 50 normally developing children, matched on age and IQ, were assessed using a composition writing task. The results contribute to prior research findings by showing that the children with ADHD performed significantly worse than the comparison groups on the majority of the planning, translation, and revision process measures usually employed to assess the quality of written compositions. Deficiencies in executive functioning or poor linguistic and metalinguistic competence could account for the results found. More research is needed to clarify the underlying causes of the written composition performance profile of children with ADHD. [ABSTRACT FROM PUBLISHER]

Recent research has disclosed a tight connection between obesity, metabolic gut microbial activities and host health. Obtaining a complete understanding of this relationship remains a major goal. Here, we conducted a comparative metagenomic and metaproteomic investigation of gut microbial communities in faecal samples taken from an obese and a lean adolescent. By analysing the diversity of 16S rDNA amplicons (10% operational phylogenetic units being common), 22 Mbp of consensus metagenome sequences (∼ 70% common) and the expression profiles of 613 distinct proteins (82% common), we found that in the obese gut, the total microbiota was more abundant on the phylum Firmicutes (94.6%) as compared with Bacteroidetes (3.2%), although the metabolically active microbiota clearly behaves in a more homogeneous manner with both contributing equally. The lean gut showed a remarkable shift towards Bacteroidetes (18.9% total 16S rDNA), which become the most active fraction (81% proteins). Although the two gut communities maintained largely similar gene repertoires and functional profiles, improved pili- and flagella-mediated host colonization and improved capacity for both complementary aerobic and anaerobic de novo B12 synthesis, 1,2-propanediol catabolism (most likely participating in de novo B12 synthesis) and butyrate production were observed in the obese gut, whereas bacteria from lean gut seem to be more engaged in vitamin B6 synthesis. Furthermore, this study provides functional evidence that variable combinations of species from different phyla could 'presumptively' fulfil overlapping and/or complementary functional roles required by the host, a scenario where minor bacterial taxa seem to be significant active contributors. [ABSTRACT FROM AUTHOR]

The present study examined the written narrations and the influence of linguistic measures on narrative competence of children with specific language impairment (SLI). A narration task was used to assess narrative abilities in 25 children with SLI and 25 normally developing children, matched on age and IQ. Results indicated that the two groups did differ in the production of narratives. The children with SLI provided short narratives, poorly organized and less cohesive. Also, writings were characterized by more syntax errors and had high proportion of phonologically inaccurate spelling errors. Hierarchical regression analysis showed that different linguistic measures - auditory comprehension, verbal fluency and sequential auditory memory - played a predictive role in narrative competence. [ABSTRACT FROM AUTHOR]

Abstract: The photocatalytic disinfection potential of TiO2- and Cu-, Zn- and Ag-promoted TiO2 embedded in polymer-based materials has been analyzed upon both ultraviolet and visible light excitations. A complete set of microorganisms including two Gram-negative (Escherichia coli and Pseudomonas earuginosa) and two Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria and a yeast (Pichia jadinii) was used throughout the study. This series covers clinically and food derived infection relevant pathogens. A kinetic modeling using an “adsorption Langmuir–Hinshelwood” type mechanism was used to interpret the disinfection tests and the performance of the different TiO2 photo-biocide agents. The results clearly indicate that Ag- and Zn-containing materials are the most effective in all conditions tested (e.g. irrespective of the microorganism nature and light energy) and this seems intimately linked with intrinsic characteristics of the radical species reaching the surface of the polymer-oxide nanocomposite films as detected by electron paramagnetic resonance. [Copyright &y& Elsevier]

Purpose: The objective of this systematic review was to characterise the methodological issues, as well as clinical, diagnosis, microbiological and treatment characteristics of patients with spinal tuberculosis. Methods: We conducted a systematic review including prospective or retrospective case series written in English, Spanish, French, German and Italian published in the period from January 1980 to March 2011. Results: Thirty-seven articles were included with a total of 1,997 patients; the median of the percentage of men was 53% (interquartile range [IQR] 48-64) and the median of the patients mean age was 43.4 (IQR 37-55). The most common symptom reported was back pain, and thoracic spine was the most frequent segment involved. Spinal plain radiography was done in 35 studies (94.6%), magnetic resonance imaging (MRI) in 26 (70.2%), computed tomography scan (CT-scan) in 13 (35%) and microbiological diagnosis in 29 (78.3%). Surgical treatment was reported in 28 articles 75.7%; finally, 24 articles reported follow-up, and in 15 of them at least 80% of patients improved. Conclusions: Spinal TB is still an important public health issue, it must be suspected in the presence of back pain or characteristic images and should be confirmed with microbiological procedures. Chemotherapy treatment is often used; in contrast, there is heterogeneity in the percentage of patients treated by surgery. [ABSTRACT FROM AUTHOR]

Summary So far only little is known about the microbial ecology of Mediterranean deep-sea hypersaline anoxic lakes (DHALs). These brine lakes were formed by evaporite dissolution/brine seeps and are important model environments to provide insights into possible metabolisms and distributions of microorganisms on the early Earth. Our study on the Lake Thetis, a new thalassohaline DHAL located South-East of the Medriff Corridor, has revealed microbial communities of contrasting compositions with a high number of novel prokaryotic candidate divisions. The major finding of our present work is co-occurrence of at least three autotrophic carbon dioxide fixation pathways in the brine-seawater interface that are likely fuelled by an active ramified sulphur cycle. Genes for the reductive acetyl-CoA and reductive TCA pathways were also found in the brine suggesting that these pathways are operational even at extremely elevated salinities and that autotrophy is more important in hypersaline environments than previously assumed. Surprisingly, genes coding for RuBisCo were found in the highly reduced brine. Three types of sulphide oxidation pathways were found in the interface. The first involves a multienzyme Sox complex catalysing the complete oxidation of reduced sulphur compounds to sulphate, the second type recruits SQR sulphide:quinone reductase for oxidation of sulphide to elemental sulphur, which, in the presence of sulphide, could further be reduced by polysulphide reductases in the third pathway. The presence of the latter two allows a maximal energy yield from the oxidation of sulphide and at the same time prevents the acidification and the accumulation of S0 deposits. Amino acid composition analysis of deduced proteins revealed a significant overrepresentation of acidic residues in the brine compared with the interface. This trait is typical for halophilic organisms as an adaptation to the brine's extreme hypersalinity. This work presents the first metagenomic survey of the microbial communities of the recently discovered Lake Thetis whose brine constitutes one of saltiest water bodies ever reported. [ABSTRACT FROM AUTHOR]

The phylogenetic and functional structure of the microbial community residing in a Ca-rich anoxic sediment of a sub-saline shallow lake (Laguna de Carrizo, initially operated as a gypsum (CaSO × 2 HO) mine) was estimated by analyzing the diversity of 16S rRNA amplicons and a 3.1 Mb of consensus metagenome sequence. The lake has about half the salinity of seawater and possesses an unusual relative concentration of ions, with Ca and SO being dominant. The 16S rRNA sequences revealed a diverse community with about 22% of the bacterial rRNAs being less than 94.5% similar to any rRNA currently deposited in GenBank. In addition to this, about 79% of the archaeal rRNA genes were mostly related to uncultured Euryarchaeota of the CCA47 group, which are often associated with marine and oxygen-depleted sites. Sequence analysis of assembled genes revealed that 23% of the open reading frames of the metagenome library had no hits in the database. Among annotated genes, functions related to (thio) sulfate and (thio) sulfonate-reduction and iron-oxidation, sulfur-oxidation, denitrification, synthrophism, and phototrophic sulfur metabolism were found as predominant. Phylogenetic and biochemical analyses indicate that the inherent physical-chemical characteristics of this habitat coupled with adaptation to anthropogenic activities have resulted in a highly efficient community for the assimilation of polysulfides, sulfoxides, and organosulfonates together with nitro-, nitrile-, and cyanide-substituted compounds. We discuss that the relevant microbial composition and metabolic capacities at Laguna de Carrizo, likely developed as an adaptation to thrive in the presence of moderate salinity conditions and potential toxic bio-molecules, in contrast with the properties of previously known anoxic sediments of shallow lakes. [ABSTRACT FROM AUTHOR]

Abstract: Presence of metallic Ag or oxidic Cu and Zn species on an anatase surface is shown to allow drastic improvement of the disinfection capability of polymer-based TiO2-containing nanocomposite films against both gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacteria and upon both ultraviolet and visible light excitations. The inorganic incorporation to the polymer matrix is reached without alteration of the main physico-chemical (structural and thermal) characteristics of the organic component. Irrespective of the excitation wavelength, the disinfection capability improvement is observed for Ag and Zn promoted film materials but not for the Cu-containing composite. A study of the optical properties attempts to interpret the biocidal enhancement observed in presence of such Ag, Cu, and Zn-containing species at inorganic–organic interfaces. [Copyright &y& Elsevier]

Recent advances in molecular microbial ecology and systems biology enhance insight into microbial community structure and functioning. They provide conceptual and technical bases for the translation of species-data and community-data into a model framework accounting for the functioning of and interactions between metabolic networks of species in multispecies environments. Function-directed and single cell-directed approaches supplement and improve metagenomics-derived community information. The topology of the metabolic network, reconstructed from a species’ genome sequence, provides insight into its metabolic environments and interactions with other microorganisms. Progress in the theoretical and experimental analysis of flux through metabolic networks paves the way for their application at the community level, contributing to understanding of material flows between and within species and their resilience toward perturbations. [Copyright &y& Elsevier]

The article analyzes administrative work in non-formal education through two fundamental aspects: one, which is related to administration in general, includes the planning, design, organization, execution, monitoring and evaluation of plans, programs, and projects according to activities and work; the other has to do with socio-educative factors and pedagogies which predominate in teaching and learning processes, inherent within the actions of this educational method. In a similar fashion, nonformal, informal and formal education is defined conceptually as well as within the fields of action of non-formal education, and principle projections in order to insert programs that deal with the conditions and necessities of diverse populations. [ABSTRACT FROM AUTHOR]

It was designed and evaluated a system that avoids in the mechanized elk incorporate to the sugarcane (Saccharum spp) bundle such impurities as stones, earth and stubbles. The principle is that the cutter should place the sugarcane stem on a metallic structure so that, this is not in contact with the floor (about 20 cm.separated) and also make form to the bundle so that “it claws” on the elk machine can take it in a single action. To determine the system effectiveness, during 2007-2008 harvest, in the area of supply of sugarmills Central Motzorongo, two aspects, the cutter yield and carried strange matter percentage were evaluated. The subjected results to the variance analysis allow asserting that the system of containers was superior to the traditional one when reducing or to eliminate the earth and stones and with it to increase the economic benefit and of operation. It is recommended to continue the generalization to all the supply areas with similar conditions to that of the study. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 incorporation into an isotactic polypropylene (iPP) polymeric matrix was achieved via a straightforward and cost-effective melting process using laboratory-made nanometric anatase-TiO2 and an industrial polymer. The structural characteristics of the resulting nanocomposite thin films as a function of the inorganic component content were examined using wide and small angle X-ray scattering (WAXS/SAXS) and vibrational Raman spectroscopy. Electron scanning and transmission microscopy (SEM/TEM) studies were also performed to provide evidence of the nanometric dispersion of the oxide within the polymer matrix, showing the presence of average aggregates of ca. 80nm. TiO2 incorporation into the iPP renders self-sterilized nanocomposite films upon light excitation, the activity of which was tested against Gram negative (P. aeruginosa) and positive (E. faecalis) bacteria. TiO2 displays maximum activity for a sample containing a 2wt.% of anatase-TiO2 irrespective of the microorganism nature. The antimicrobial activity of the nanocomposite films is significantly enhanced with respect to that of the oxide alone. This key fact is interpreted on physical basis with the help of a complete optical (UV–vis and photoluminescence) and electron paramagnetic resonance (EPR) characterization. [Copyright &y& Elsevier]

In recent years, the application of approaches for harvesting DNA from the environment, the so-called, ‘metagenomic approaches’ has proven to be highly successful for the identification, isolation and generation of novel enzymes. Functional screening for the desired catalytic activity is one of the key steps in mining metagenomic libraries, as it does not rely on sequence homology. In this mini-review, we survey high-throughput screening tools, originally developed for directed evolution experiments, which can be readily adapted for the screening of large libraries. In particular, we focus on the use of in vitro compartmentalization (IVC) approaches to address potential advantages and problems the merger of culture-independent and IVC techniques might bring on the mining of enzyme activities in microbial communities. [ABSTRACT FROM AUTHOR]

Recent progress has revealed that the capture of genetic resources of complex microbial communities in metagenome libraries allows the discovery of a richness of new enzymatic diversity that had not previously been imagined. Activity-based screening of such libraries has demonstrated that this new diversity is not simply variations on known sequence themes, but rather the existence of entirely new sequence classes and novel functionalities. This new diversity, the surface of which has thus far only been scratched, constitutes potential for a wealth of new and improved applications in industry, medicine, agriculture, etc., and promises to facilitate in a significant manner our transition to a sustainable society, by contributing to the transition to renewable sources of energy, chemicals and materials, the lowering of pollutant burdens, lower processes energies, etc. Current bottlenecks in metagenomics include insufficient functional characterization and amplifying non-validated annotations of proteins in databases. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We describe here an extraordinary purple-colored DNA ligase, LigFa, from the acidophilic ferrous iron-oxidizing archaeon Ferroplasma acidiphilum, a di-ferric enzyme with an extremely low pH activity optimum. Unlike any other DNA ligase studied to date, LigFa contains two Fe3+-tyrosinate centers and lacks any requirement for either Mg2+ or K~ for activity. DNA ligases from closest phylogenetic and ecophysiological relatives have normal pH optima (6.0-7.5), lack iron, and require Mg2+/K+ for activity. Ferric iron retention is pH-dependent, with release resulting in partial protein unfolding and loss of activity. Reduction of the Fe3+ to Fe2+ results in an 80% decrease in DNA substrate binding and an increase in the pH activity optimum to 5.0. DNA binding induces significant conformational change around the iron site(s), suggesting that the ferric irons of LigFa act both as structure organizing and stabilizing elements and as Lewis acids facilitating DNA binding at low pH. [ABSTRACT FROM AUTHOR]

Current advances in metagenomics have revolutionized the research in fields of microbial ecology and biotechnology, enabling not only a glimpse into the uncultured microbial population and mechanistic understanding of possible biogeochemical cycles and lifestyles of extreme organisms but also the high-throughput discovery of new enzymes for industrial bioconversions. Nowadays, the genetic and enzymatic differences across the gradients from ‘neutral and pristine’ to ‘extreme and polluted’ environments are well documented. Yet, extremophilic organisms are possibly the least well understood because our ability to study and understand their metabolic potential has been hampered by our inability to isolate pure cultures. There are at least two obstacles for reaping the fruit of the microbial diversity of extremophiles: first, in spite of the recent progress in development of new culturing techniques most extremophiles cannot be cultured using traditional culturing technologies; and second, the problem of the very low biomass densities often occurs under the conditions hostile for life, which often do not yield enough DNA and reduces the effectiveness of cloning. [Copyright &y& Elsevier]

Ferroplasma is a genus of the Archaea, one of the three branches of the tree of life, and belongs to the order Thermoplasmatales (Euryarchaeota), which contains the most acidophilic microbes yet known. Ferroplasma species live in acid mine drainage, acidic pools and environments containing sulphidic ores such as pyrite and characterized by pH values of 0–2 and high concentrations of ferrous iron and other heavy metals. F. acidiphilum strain YT is a chemoautotroph that grows optimally at pH 1.7 and gains energy by oxidizing ferrous iron and carbon by the fixation of carbon dioxide. Here we show that 86% of 189 investigated cellular proteins of F. acidiphilum are iron-metalloproteins. These include proteins with deduced structural, chaperone and catalytic roles, not described as iron-metalloproteins in any other organism so far investigated. The iron atoms in the proteins seem to organize and stabilize their three-dimensional structures, to act as ‘iron rivets’. Analysis of proteins of the phylogenetic neighbour Picrophilus torridus and of the habitat neighbour Acidithiobacillus ferrooxidans revealed far fewer and only typical metalloproteins. F. acidiphilum therefore has a currently unique iron-protein-dominated cellular machinery and biochemical phylogeny. [ABSTRACT FROM AUTHOR]

Modern biocatalysis is developing new and precise tools to improve a wide range of production processes, which reduce energy and raw material consumption and generate less waste and toxic side-products. Biocatalysis is also achieving new advances in environmental fields, from enzymatic bioremediation to the synthesis of renewable and clean energies and biochemical cleaning of ‘dirty’ fossil fuels. Despite the obvious benefits of biocatalysis, the major hurdles hindering the exploitation of the repertoire of enzymatic processes are, in many cases, the high production costs and the low yields obtained. This article will discuss these issues, pinpointing specific new advances in recombinant DNA techniques amenable to future biocatalyst development, in addition to drawing the attention of the biotechnology community to the active pursuit and development of environmental biocatalysis, from remediation with enzymes to novel green processes. [Copyright &y& Elsevier]

A metagenome expression library of bulk DNA extracted from the rumen content of a dairy cow was established in a phage lambda vector and activity-based screening employed to explore the functional diversity of the microbial flora. Twenty-two clones specifying distinct hydrolytic activities (12 esterases, nine endo-β-1,4-glucanases and one cyclodextrinase) were identified in the library and characterized. Sequence analysis of the retrieved enzymes revealed that eight (36%) were entirely new and formed deep-branched phylogenetic lineages with no close relatives among known ester- and glycosyl-hydrolases. Bioinformatic analyses of the hydrolase gene sequences, and the sequences and contexts of neighbouring genes, suggested tentative phylogenetic assignments of the rumen organisms producing the retrieved enzymes. The phylogenetic novelty of the hydrolases suggests that some of them may have potential for new applications in biocatalysis. [ABSTRACT FROM AUTHOR]

Advances in the field of genomics and ‘metagenomics’ have dramatically revised our view of microbial biodiversity and its potential for biotechnological applications. Considering the estimation that >99% of microorganisms in most environments are not amenable to culturing, very little is known about their genomes, genes and encoded enzymatic activities. The isolation, archiving and analysis of environmental DNA (or so-called ‘metagenomes’) has enabled us to mine microbial diversity, allowing us to access their genomes, identify protein coding sequences and even to reconstruct biochemical pathways, providing insights into the properties and functions of these organisms. The generation and analysis of (meta)genomic libraries is thus a powerful approach to harvest and archive environmental genetic resources. It will enable us to identify which organisms are present, what they do, and how their genetic information can be beneficial to mankind. [Copyright &y& Elsevier]

Summary: We created a metagenome expression library from the brine:seawater interface of the Urania hypersaline basin, screened it for esterases, and characterized five of these. Two had no significant sequence homology to known esterases, hydrolyzed both carboxylesters and thioesters, and exhibited unusual, habitat-specific characteristics (preference for high hydrostatic pressure and salinity). One has an unusual structural signature incorporating three catalytic active centers mediating distinct hydrolytic activities and an adaptive tertiary-quaternary structure that alters between three molecular states, according to the prevailing physicochemical conditions. Some of the esterases have high activities, specificities, enantioselectivities, and exceptional stability in polar solvents, and they are therefore potentially useful for industrial biotransformations. One possesses the highest enantioselectivity toward an ester of the important chiral synthon solketal (E: 126[S]; 98%ee). [Copyright &y& Elsevier]

Abstract: The lipases from Thermomyces lanuginosus (immobilized by granulation with silica) and Candida antarctica B (adsorbed on Lewatit, “Novozym 435”) were comparatively assayed for the synthesis of sugar esters by transesterification of sugars with fatty acid vinyl esters in 2-methyl-2-butanol:dimethylsulfoxide mixtures. We found that lipase from C. antarctica B is particularly useful for the preparation of 6,6′-di-acylsucrose, whereas T. lanuginosus lipase catalyzes selectively the synthesis of 6-O-acylsucrose. The granulated T. lanuginosus lipase retained more than 80% of its initial activity after 20 cycles of 6h. Both lipases were similarly effective for the regioselective synthesis of 6′-O-palmitoylmaltose and 6-O-lauroylglucose. The effect of the synthesized sugar esters on the growth in liquid medium of various microorganisms (Gram-positive, Gram-negative and yeasts) was evaluated. 6-O-lauroylsucrose and 6′-O-lauroylmaltose inhibited the growth of Bacillus sp. at a concentration of 0.8mg/ml, and of Lactobacillus plantarum at 4mg/ml. Sucrose dilaurates and 6-O-lauroylglucose did not show antimicrobial activity, probably due to their low aqueous solubility. As regards the inhibition of yeasts, none of the tested carbohydrate esters inhibited significantly the growth of Zygosaccharomyces rouxii and Pichia jadinii. [Copyright &y& Elsevier]

A new principle for expression of heat-sensitive recombinant proteins in Escherichia coli at temperatures close to 4°C was experimentally evaluated. This principle was based on simultaneous expression of the target protein with chaperones (Cpn60 and Cpn10) from a psychrophilic bacterium, Oleispira antarctica RB8T, that allow E. coli to grow at high rates at 4°C (maximum growth rate, 0.28 h-1) (M. Ferrer, T. N. Chernikova, M. Yakimov, P. N. Golyshin, and K. N. Timmis, Nat. Biotechnol. 21:1266–1267, 2003). The expression of a temperature-sensitive esterase in this host at 4 to 10°C yielded enzyme specific activity that was 180-fold higher than the activity purified from the non-chaperonin-producing E. coli strain grown at 37°C (32,380 versus 190 μmol min-1 g-1). We present evidence that the increased specific activity was not due to the low growth temperature per se but was due to the fact that low temperature was beneficial to folding, with or without chaperones. This is the first report of successful use of a chaperone-based E. coli strain to express heat-labile recombinant proteins at temperatures below the theoretical minimum growth temperature of a common E. coli strain (7.5°C). [ABSTRACT FROM AUTHOR]

The cpn60 and cpn10 genes from psychrophilic bacterium, Oleispira antarctica RB8, showed a positive effect in Escherichia coli growth at low temperature, shifting its theoretical minimal growth temperature from +7.5°C to −13.7°C [Ferrer, M., Chernikova, T.N., Yakimov, M., Golyshin, P.N., and Timmis, K.N. (2003) Nature Biotechnol 21: 1266–1267]. To provide experimental support for this finding, Cpn60 and 10 were overproduced in E. coli and purified to apparent homogeneity. Recombinant O.Cpn60 was identical to the native protein based on tetradecameric structure, and it dissociates during native PAGE. Gel filtration and native PAGE revealed that, in vivo and in vitro, (O.Cpn60)7 was the active oligomer at 4–10°C, whereas at > 10°C, this complex was converted to (O.Cpn60)14. The dissociation reduces the ATP consumption (energy-saving mechanism) and increases the refolding capacity at low temperatures. In order for this transition to occur, we demonstrated that K468 and S471 may play a key role in conforming the more advantageous oligomeric state in O.Cpn60. We have proved this hypothesis by showing that single and double mutations in K468 and S471 for T and G, as in E.GroEL, produced a more stable double-ring oligomer. The optimum temperature for ATPase and chaperone activity for the wild-type chaperonin was 24–28°C and 4–18°C, whereas that for the mutants was 45–55°C and 14–36°C respectively. The temperature inducing unfolding (TM) increased from 45°C to more than 65°C. In contrast, a single ring mutant, O.Cpn60SR, with three amino acid substitutions (E461A, S463A and V464A) was as stable as the wild type but possessed refolding activity below 10°C. Above 10°C, this complex lost refolding capacity to the detriment of the double ring, which was not an efficient chaperone at 4°C as the single ring variant. We demonstrated that expression of O.Cpn60WT and O.Cpn60SR leads to a higher growth of E. coli at 4°C (µmax, 0.22 and 0.36 h−1 respectively), whereas at 10–15°C, only E. coli cells expressing O.Cpn60 or O.Cpn60DR grew better than parental cells (– cpn). These results clearly indicate that the single-to-double ring transition in Oleispira chaperonin is a wild-type mechanism for its thermal acclimation. Although previous studies have also reported single-to-double ring transitions under many circumstances, this is the first clear indication that single-ring chaperonins are necessary to support growth when the temperature falls from 37°C to 4°C. [ABSTRACT FROM AUTHOR]

Lipase from Thermomyces lanuginosus (formerly Humicola lanuginosa ) was immobilized using granulation by incubating low-particle-size silica with the lipase. Granules with a particle diameter in the range 0.3-1 mm were obtained. The immobilized lipase was tested in the acylation of sucrose with vinyl laurate in mixtures of tert -amyl alcohol: dimethyl sulfoxide. Results were compared with immobilization of enzyme by adsorption on polypropylene (Accurel EP100), deposition on Celite by precipitation, and covalent attachment to Eupergit C. Granulated lipase converted >95% of sucrose into 6- O -lauroylsucrose in 6 h. Accurel-lipase was also very active, converting 70% of sucrose into monoester in 2 h. The residual activity of granules after five reaction cycles under the best reaction conditions was 72%; this value was considerably higher than the one observed for the same lipase adsorbed on Accurel (15% residual activity after five cycles). [ABSTRACT FROM AUTHOR]