Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Influenza Other Respir Viruses ; 18(6): e13340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890805

RESUMO

BACKGROUND: Viral recombination that occurs by exchanging genetic materials between two viral genomes coinfecting the same host cells is associated with the emergence of new viruses with different virulence. Herein, we detected a patient coinfected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta and Omicron variants and identified various recombinants in the SARS-CoV-2 full-length spike gene using long-read and Sanger sequencing. METHODS: Samples from five patients in Japan with household transmission of coronavirus disease 2019 (COVID-19) were analyzed using molecular assays for detection and identification of SARS-CoV-2. Whole-genome sequencing was conducted using multiplex PCR with short-read sequencing. RESULTS: Among the five SARS-CoV-2-positive patients, the mutation-specific assay identified the Delta variant in three, the Omicron variant in one, and an undetermined in one. The undermined patient was identified as Delta using whole-genome sequencing, but samples showed a mixed population of Delta and Omicron variants. This patient was analyzed for viral quasispecies by long-read and Sanger sequencing using a full-length spike gene amplicon. In addition to the Delta and Omicron sequences, the viral quasispecies analysis identified nine different genetic recombinant sequences with various breakpoints between Delta and Omicron sequences. The nine detected recombinant sequences in the spike gene showed over 99% identity with viruses that were detected during the Delta and Omicron cocirculation period from the United States and Europe. CONCLUSIONS: This study demonstrates that patients coinfected with different SARS-CoV-2 variants can generate various viral recombinants and that various recombinant viruses may be produced during the cocirculation of different variants.


Assuntos
COVID-19 , Coinfecção , Genoma Viral , Recombinação Genética , SARS-CoV-2 , Sequenciamento Completo do Genoma , Humanos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , COVID-19/virologia , COVID-19/complicações , Coinfecção/virologia , Genoma Viral/genética , Glicoproteína da Espícula de Coronavírus/genética , Masculino , Japão , Feminino , Filogenia , Mutação , Pessoa de Meia-Idade
2.
J Infect Chemother ; 28(7): 1001-1004, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35430092

RESUMO

A concern has been raised that the persistent COVID-19 infection in an immunocompromised host can be the source of the SARS-CoV-2 variants. This is the case of a 61-year-old man in complete remission of a follicular lymphoma after six cycles of rituximab and bendamustine with additional two cycles of rituximab completed eight months prior to the episode of COVID-19 pneumonia. The patient's respiratory failure was long-lasting, and required mechanical ventilation until day 75. Acquired immunity tested negative throughout the observational period. The viral RNA was detectable until day 100 while the infectious virus was isolated until day 79. Seven haplotypes were identified and the non-synonymous mutations accumulated in the spike gene which included E484Q and S494P. In the management of COVID-19 cases with suppressed immune statuses, initial evaluation of existing immunity and monitoring for infectiousness throughout the clinical course including the convalescent stage may be necessary.


Assuntos
COVID-19 , SARS-CoV-2 , Haplótipos , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Rituximab/uso terapêutico , SARS-CoV-2/genética
3.
Infant Ment Health J ; 42(5): 705-717, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34449892

RESUMO

We aimed to clarify the factor structure of a bonding measure among Japanese fathers with infants and the factors associated with the subscales. Among fathers of children attending the 4-month health checkup, the Japanese version of the Mother-to-Infant Bonding Scale had a two-factor structure comprising "anger" and "lack of affection." Anger was associated with fathers' work demands and poor mental condition, and lack of affection with fathers' older age, poor mental condition, and interpersonal problems at home. Paternal parenting support needs to account for not only the fathers themselves, but also interpersonal communication at home and in the work environment.


Nos propusimos clarificar la estructura de factores de una medida de acercamiento afectivo entre los papás japoneses con infantes y los factores asociados con las subescalas. Entre los papás de niños que asistían al chequeo de salud de 4 meses, la versión japonesa de la Escala de Acercamiento Afectivo Madre a Infante tuvo una estructura de dos factores que comprende "ira" y "falta de afecto." La "Ira" se asoció con las responsabilidades del trabajo de los papás y la débil condición mental, y la "falta de afecto" con la más vieja edad de los papás, la débil condición mental y los problemas interpersonales en casa. La crianza paterna apoya las necesidades de dar cuenta no sólo de los padres mismos, sino también de la comunicación interpersonal en casa y el ambiente de trabajo.


Notre but était de clarifier la structure de facteur d'une mesure de lien entre les pères japonais de nourrissons et les facteurs liés aux sous-échelles. Parmi les pères d'enfants présents pour leur visite médicale de 4 mois la version japonaise de l'Echelle de Lien Mère-Nourrisson était une structure de deux facteurs comprenant "la colère" et "le manque d'affection". "La colère" était liée aux exigences du travail des pères et à une condition mentale moins élevée, et "le manque d'attention" était lié à l'âge plus élevés des pères, à une condition mentale moins élevée et à des problèmes relationnels à la maison. Le soutien de parentage paternel a besoin d'être pris en compte non seulement pour ce qui concerne les pères eux-mêmes mais aussi la communication relationnelle à la maison et l'environnement au travail.


Assuntos
Saúde da Criança , Relações Pai-Filho , Idoso , Criança , Pai , Feminino , Humanos , Lactente , Japão , Masculino , Poder Familiar
4.
J Epidemiol ; 31(12): 608-614, 2021 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-32863372

RESUMO

BACKGROUND: Discrepancies between parents' reports of paternal parenting have been gaining attention, but epidemiological evidence is scarce in Asia. This study aimed to clarify agreement/discrepancy between paternal and maternal recognition of paternal parenting and the association between actual paternal parenting time and background factors. METHODS: Data from couples whose children attended 4-month child health check-ups in Fukushima City were analyzed (N = 509). Based on paternal recognition of paternal parenting (PRPP) and maternal recognition of paternal support (MRPS), couples were classified into four groups. Each group's paternal household work and parenting time were analyzed. Univariable and multivariable analysis were performed to investigate the association between agreement/discrepancy and background factors of children and parents. RESULTS: Frequency of positive agreement (PRPP+ and MRPS+) was 83.9%, whereas negative agreement (PRPP- and MRPS-) was 2.6%. As for discrepancy, PRPP+ and MRPS- was 8.4% and PRPP- and MRPS+ was 5.1%. Fathers' total median parenting time was 2 (weekdays) and 6 (weekends) hours, and showed significant differences among the four groups. Multivariable analysis revealed that compared to positive agreement, maternal mental health condition and pregnancy intention were significantly associated with the discrepancy PRPP+ and MRPS-, paternal mental health condition and marital satisfaction with the discrepancy PRPP- and MRPS+, and maternal mental health condition with negative agreement. CONCLUSIONS: We identified differences in parenting time and mental health characteristics among couples depending on agreement/discrepancy in recognition of paternal parenting. Assessing both parents' profiles is necessary in clinical practice to promote paternal participation in childcare.


Assuntos
Mães , Poder Familiar , Criança , Estudos Transversais , Pai , Feminino , Humanos , Masculino , Gravidez , Autoavaliação (Psicologia)
5.
Artigo em Inglês | MEDLINE | ID: mdl-32197447

RESUMO

Little scientific evidence exists on ways to decrease the psychological stress experienced by disaster responders, or how to maintain and improve their mental health. In an effort to grasp the current state of research, we examined research papers, agency reports, the manuals of aid organisations, and educational materials, in both English and Japanese. Using MEDLINE, Ichushi-Web (Japanese search engine), Google Scholar, websites of the United Nations agencies, and the database of the Grants System for Japan's Ministry of Health, Labour, and Welfare, 71 pertinent materials were identified, 49 of which were analysed. As a result, 55 actions were extracted that could potentially protect and improve the mental health of disaster responders, leading to specific recommendations. These include (1) during the pre-activity phase, enabling responders to anticipate stressful situations at a disaster site and preparing them to monitor their stress level; (2) during the activity phase, engaging in preventive measures against on-site stress; (3) using external professional support when the level of stress is excessive; and (4) after the disaster response, getting back to routines, sharing of experiences, and long-term follow-up. Our results highlighted the need to offer psychological support to disaster responders throughout the various phases of their duties.


Assuntos
Desastres , Saúde Mental , Estresse Psicológico , Serviços de Saúde , Japão
6.
Health Care Women Int ; 41(3): 330-344, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31335256

RESUMO

Postpartum depression is a serious problem not only for mothers, but also for their children and families. Evidence is scarce on the effectiveness of couple-targeted antenatal interventions aimed at preventing postpartum depression in Asia. Therefore, we implemented an antenatal parenting support program from Australia ("empathy program") at three sites in Japan, and assessed the characteristics of participating couples and changes in their mental health indicators before and after the program (during pregnancy and 6 weeks postpartum, respectively). In this program, participant couples discussed concerns during pregnancy and a "difficult day" scenario with other same-gender participants and then with their own partners. In total, 100 couples attended the program. Among 60 participating mothers, 20% screened positive for maternal depression symptoms (defined as an Edinburgh Postnatal Depression Scale greater than 9). Changes in paternal empathy and maternal antenatal Edinburgh Postnatal Depression Scale score were significantly associated with maternal postpartum Edinburgh Postnatal Depression Scale score in multivariable analyses. Our results indicate that a key in preventing postpartum depression is paternal involvement and long-term support from antenatal phase.


Assuntos
Depressão Pós-Parto/prevenção & controle , Pai/psicologia , Mães/psicologia , Poder Familiar/psicologia , Parto/psicologia , Educação de Pacientes como Assunto , Estresse Psicológico/prevenção & controle , Adulto , Criança , Depressão Pós-Parto/psicologia , Feminino , Humanos , Japão , Masculino , Saúde Mental , Período Pós-Parto , Gravidez , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/psicologia , Avaliação de Programas e Projetos de Saúde , Escalas de Graduação Psiquiátrica , Apoio Social
7.
Artigo em Inglês | MEDLINE | ID: mdl-30380803

RESUMO

Young women in their late teens and early 20s are at the highest risk for depression onset. The present study aimed to assess depressive symptoms among female college students in Fukushima. More specifically, it aimed to clarify factors predicting possible symptom profiles, with an emphasis on determining how nuclear radiation risks affect the reporting of depression symptoms. A cross-sectional survey was conducted of 310 female students at a college in the Fukushima prefecture, Japan, in December 2015, and 288 participants submitted valid questionnaires. In total, 222 (77.1%) participants lived in Fukushima at the time of the Great East Japan Earthquake. The measures included the World Health Organization-Five Well-Being Index, the Fukushima Future Parents Attitude Measure, and risk perception of radiation health effects. A total of 46.5% of participants reported depressive symptoms. Path analysis revealed that higher radiation risk perceptions and reduced efficacy with reproduction related to a decline in self-esteem and self-efficacy, which was subsequently associated with increased depressive symptoms. These findings highlight the importance of radiation education among children and young adults, both after a nuclear accident and during disaster preparation, particularly in the context of reproductive and mental health.


Assuntos
Depressão/psicologia , Acidente Nuclear de Fukushima , Saúde Mental/estatística & dados numéricos , Lesões por Radiação/psicologia , Estudantes/psicologia , Adolescente , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Lesões por Radiação/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
8.
Acute Med Surg ; 2(3): 183-189, 2015 07.
Artigo em Inglês | MEDLINE | ID: mdl-29123718

RESUMO

Aim: Bystander cardiopulmonary resuscitation including automated external defibrillator use increases the chance of survival after out-of-hospital cardiac arrest. However, bystanders may be distressed by witnessing out-of-hospital cardiac arrest and may hesitate to initiate cardiopulmonary resuscitation. The present study examined factors associated with layperson confidence in carrying out resuscitation of out-of-hospital cardiac arrest patients. Methods: We carried out a cross-sectional survey in February 2012. Laypeople were asked about background characteristics, whether they had performed cardiopulmonary resuscitation, had received cardiopulmonary resuscitation training, were aware of the location of the neighborhood automated external defibrillator, and felt confident in performing resuscitation, and their potential emotional distress if a resuscitation attempt were to prove unsuccessful. Results: Participants comprised 4,853 respondents. Of these, 2,372 (49%) had received cardiopulmonary resuscitation training, and 3,607 (74%) knew where the neighborhood automated external defibrillator was located. Confidence in performing chest compressions was reported by 2,667 (55%), confidence in performing rescue breathing by 2,498 (52%), and confidence in using an automated external defibrillator by 2,822 (58%). Potential emotional distress if a resuscitation attempt proved unsuccessful was reported by 4,247 (88%). Multivariate regression analysis showed that having carried out cardiopulmonary resuscitation, having received cardiopulmonary resuscitation training, and awareness of the neighborhood automated external defibrillator location were significantly associated with confidence in performing cardiopulmonary resuscitation. Conclusions: Our results suggest that more extensive cardiopulmonary resuscitation training and information regarding neighborhood automated external defibrillator locations may increase layperson confidence in initiating resuscitation.

9.
Acute Med Surg ; 1(3): 135-144, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29930837

RESUMO

AIM: This study investigated the association between the number of phone calls made to hospitals from ambulances requesting if they can accept prehospital emergency patients with cardiovascular events, and the prehospital transportation time. METHODS: Using ambulance records, we retrospectively enrolled adult patients suffering acute myocardial infarction from 1998 to 2007, and out-of-hospital cardiac arrest of cardiac origin from 2000 to 2007, transported to medical institutions by the emergency medical service in Osaka City. RESULTS: During the study period, 8,596 patients with acute myocardial infarction without arrest and 9,283 out-of-hospital cardiac arrests of cardiac origin were registered. The hospital arrival time (from patient's call until hospital arrival) increased along with the increasing number of phone calls to hospitals from ambulances for patients with acute myocardial infarction (from 23.2 min with one phone call to 39.7 min with ≥5 phone calls; P for trend <0.001), and for those with out-of-hospital cardiac arrest (from 24.4 min with one phone call to 36.6 min with ≥5 phone calls; P for trend <0.001). In a multivariable analysis, chronological factors such as weekend and night-time were significantly associated with an increment in the phone calls to hospitals from ambulances. CONCLUSIONS: From ambulance records in Osaka City, we showed that the increased number of phone calls to hospitals from ambulances led to prolongation of the hospital arrival time.

10.
Microb Cell Fact ; 11: 82, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22709572

RESUMO

BACKGROUND: Reproduction and sustainability are important for future society, and bioprocesses are one technology that can be used to realize these concepts. However, there is still limited variation in bioprocesses and there are several challenges, especially in the operation of energy-requiring bioprocesses. As an example of a microbial platform for an energy-requiring bioprocess, we established a process that efficiently and enzymatically synthesizes 2'-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase. This method consists of the coupling reactions of the reversible nucleoside degradation pathway and energy generation through the yeast glycolytic pathway. RESULTS: Using E. coli that co-express deoxyriboaldolase and phosphopentomutase, a high amount of 2'-deoxyribonucleoside was produced with efficient energy transfer under phosphate-limiting reaction conditions. Keeping the nucleobase concentration low and the mixture at a low reaction temperature increased the yield of 2'-deoxyribonucleoside relative to the amount of added nucleobase, indicating that energy was efficiently generated from glucose via the yeast glycolytic pathway under these reaction conditions. Using a one-pot reaction in which small amounts of adenine, adenosine, and acetone-dried yeast were fed into the reaction, 75 mM of 2'-deoxyinosine, the deaminated product of 2'-deoxyadenosine, was produced from glucose (600 mM), acetaldehyde (250 mM), adenine (70 mM), and adenosine (20 mM) with a high yield relative to the total base moiety input (83%). Moreover, a variety of natural dNSs were further synthesized by introducing a base-exchange reaction into the process. CONCLUSION: A critical common issue in energy-requiring bioprocess is fine control of phosphate concentration. We tried to resolve this problem, and provide the convenient recipe for establishment of energy-requiring bioprocesses. It is anticipated that the commercial demand for dNSs, which are primary metabolites that accumulate at very low levels in the metabolic pool, will grow. The development of an efficient production method for these compounds will have a great impact in both fields of applied microbiology and industry and will also serve as a good example of a microbial platform for energy-requiring bioprocesses.


Assuntos
Desoxiadenosinas/metabolismo , Metabolismo Energético , Escherichia coli/metabolismo , Microbiologia Industrial/métodos , Saccharomyces cerevisiae/metabolismo , Acetaldeído/metabolismo , Desoxiadenosinas/química , Escherichia coli/genética , Engenharia Genética , Glucose/metabolismo , Estrutura Molecular , Saccharomyces cerevisiae/genética
11.
Circ J ; 75(12): 2821-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21959265

RESUMO

BACKGROUND: Detailed characteristics of those who experience an out-of-hospital cardiac arrest (OHCA) with public-access defibrillation (PAD) are unknown. METHODS AND RESULTS: A prospective, population-based observational study involving consecutive OHCA patients with emergency responder resuscitation attempts was conducted from July 1, 2004 through December 31, 2008 in Osaka City. We extracted data for OHCA patients shocked by a public-access automated external defibrillator (AED) and evaluated the patients' and rescuers' characteristics. The main outcome measure was neurologically favorable 1-month survival. During the study period, 10,375 OHCA patients were registered and of 908 patients suffering ventricular fibrillation arrest, 53 (6%) received public-access AED shocks by lay-rescuers, with the proportion increasing from 0% in 2004 to 11% in 2008 (P for trend<0.001). Railway stations (34%) were the places where PAD shocks were most frequently delivered, followed by nursing homes (11%), medical facilities (9%), and fitness facilities (7%). In 57% of cases, the subject received public-access AED shocks delivered by non-medical persons, including employees of railway companies (13%), school teachers (6%), employees of fitness facilities (6%), and security guards (6%). The proportion of neurologically favorable 1-month survival tended to increase from 0% in 2005 to 58% in 2008 (P for trend=0.081). CONCLUSIONS: Railway stations are the most common places where shocks by public-access AEDs were delivered in large urban communities of Japan, and among lay-rescuers railway station workers use AEDs more frequently.


Assuntos
Desfibriladores , Cardioversão Elétrica , Parada Cardíaca Extra-Hospitalar/terapia , Ressuscitação , População Urbana , Adulto , Idoso , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/mortalidade , Estudos Prospectivos , Ressuscitação/instrumentação , Ressuscitação/métodos
12.
N Biotechnol ; 26(1-2): 75-82, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19818317

RESUMO

Bacillus sphaericus AKU 229 was found to produce an acetaldehyde-tolerant and phosphorylated compound-tolerant phosphopentomutase useful for enzymatic 2'-deoxyribonucleoside production. The gene encoding the phosphopentomutase was cloned and expressed in Escherichia coli. The E. coli expressing B. sphaericus phosphopentomutase was an excellent catalyst as to production of 2'-deoxyribonucleoside in the presence of acetaldehyde and phosphorylated compounds such as fructose 1,6-diphosphate, and d-glyceraldehyde 3-phosphate, which are derived from glucose through glycolysis with yeast cells, and exist abundantly in the practical reaction mixture for enzymatic 2'-deoxyribonucleoside production.


Assuntos
Bacillus/enzimologia , Biotecnologia/métodos , Desoxirribonucleosídeos/biossíntese , Fosfotransferases/metabolismo , Acetaldeído/farmacologia , Sequência de Aminoácidos , Bacillus/efeitos dos fármacos , Bacillus/genética , Biocatálise/efeitos dos fármacos , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Redes e Vias Metabólicas/efeitos dos fármacos , Dados de Sequência Molecular , Fosforilação/efeitos dos fármacos , Fosfotransferases/química , Fosfotransferases/genética , Alinhamento de Sequência , Transformação Genética/efeitos dos fármacos
13.
Kansenshogaku Zasshi ; 83(1): 36-44, 2009 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-19227223

RESUMO

We examined water from 182 non-circulating hot spring bathing facilities in Japan for possible Legionella occurrence from June 2005 to December 2006, finding Legionella-positive cultures in 119 (29.5%) of 403 samples. Legionellae occurrence was most prevalent in bathtub water (39.4%), followed by storage tank water (23.8%), water from faucets at the bathtub edge (22.3%), and source-spring water (8.3%), indicating no statistically significant difference, in the number of legionellae, having an overall mean of 66 CFU/100mL. The maximum number of legionellae in water increased as water was sampled downstream:180 CFU/100 mL from source spring, 670 from storage tanks, 4,000 from inlet faucets, and 6,800 from bathtubs. The majority--85.7%--of isolated species were identified as L. pneumophila : L. pneumophila serogroup (SG) 1 in 22%, SG 5 in 21%, and SG 6 in 22% of positive samples. Multivariate logistic regression models used to determine the characteristics of facilities and sanitary management associated with Legionella contamination indicated that legionellae was prevalent in bathtub water under conditions where it was isolated from inlet faucet/pouring gate water (odds ratio [OR] = 6.98, 95% confidence interval [CI] = 2.14 to 22.8). Risk of occurrence was also high when the bathtub volume exceeded 5 m3 (OR = 2.74, 95% CI = 1.28 to 5.89). Legionellae occurrence was significantly reduced when the bathing water pH was lower than 6.0 (OR = 0.12, 95% CI = 0.02 to 0.63). Similarly, occurrence was rare in inlet faucet water or the upper part of the plumbing system for which pH was lower than 6.0 (OR = 0.06, 95% CI = 0.01 to 0.48), and when the water temperature was maintained at 55 degrees C or more (OR = 0.10, 95% CI = 0.01 to 0.77). We also examined the occurrence of amoeba, Mycobacterium spp., Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus in water samples.


Assuntos
Banhos , Legionella/isolamento & purificação , Microbiologia da Água , Banhos/normas , Concentração de Íons de Hidrogênio , Fatores de Risco , Temperatura
14.
Biotechnol Lett ; 28(12): 877-81, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16786272

RESUMO

A one-pot enzymatic synthesis of 2'-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase was established. Glycolysis by baker's yeast (Saccharomyces cerevisiae) generated ATP which was used to produce D: -glyceraldehyde 3-phosphate production from glucose via fructose 1,6-diphosphate. The D: -glyceraldehyde 3-phosphate produced was transformed to 2'-deoxyribonucleoside via 2-deoxyribose 5-phosphate and then 2-deoxyribose 1-phosphate in the presence of acetaldehyde and a nucleobase by deoxyriboaldolase, phosphopentomutase expressed in Escherichia coli, and a commercial nucleoside phosphorylase. About 33 mM 2'-deoxyinosine was produced from 600 mM glucose, 333 mM acetaldehyde and 100 mM adenine in 24 h. 2'-Deoxyinosine was produced from adenine due to the adenosine deaminase activity of E. coli transformants.


Assuntos
Desoxirribonucleosídeos/biossíntese , Escherichia coli/metabolismo , Saccharomyces/enzimologia , Transformação Bacteriana/genética , Acetaldeído/metabolismo , Biotecnologia/métodos , Escherichia coli/genética , Glucose/metabolismo , Pentosiltransferases/farmacologia , Fosfotransferases/metabolismo , Ribosemonofosfatos/metabolismo , Transformação Bacteriana/fisiologia
15.
Biosci Biotechnol Biochem ; 70(6): 1371-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16794316

RESUMO

2-Deoxyribose 5-phosphate production through coupling of the alcoholic fermentation system of baker's yeast and deoxyriboaldolase-expressing Escherichia coli was investigated. In this process, baker's yeast generates fructose 1,6-diphosphate from glucose and inorganic phosphate, and then the E. coli convert the fructose 1,6-diphosphate into 2-deoxyribose 5-phosphate via D-glyceraldehyde 3-phosphate. Under the optimized conditions with toluene-treated yeast cells, 356 mM (121 g/l) fructose 1,6-diphosphate was produced from 1,111 mM glucose and 750 mM potassium phosphate buffer (pH 6.4) with a catalytic amount of AMP, and the reaction supernatant containing the fructose 1,6-diphosphate was used directly as substrate for 2-deoxyribose 5-phosphate production with the E. coli cells. With 178 mM enzymatically prepared fructose 1,6-diphosphate and 400 mM acetaldehyde as substrates, 246 mM (52.6 g/l) 2-deoxyribose 5-phosphate was produced. The molar yield of 2-deoxyribose 5-phosphate as to glucose through the total two step reaction was 22.1%. The 2-deoxyribose 5-phosphate produced was converted to 2-deoxyribose with a molar yield of 85% through endogenous or exogenous phosphatase activity.


Assuntos
Acetaldeído/metabolismo , Álcoois/metabolismo , Aldeído Liases/metabolismo , Escherichia coli/metabolismo , Glucose/metabolismo , Ribosemonofosfatos/biossíntese , Saccharomyces cerevisiae/metabolismo , Acetaldeído/química , Escherichia coli/genética , Fermentação , Frutosedifosfatos/biossíntese , Glucose/química , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Estrutura Molecular , Fosfatos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Temperatura
16.
Appl Microbiol Biotechnol ; 71(5): 615-21, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16283293

RESUMO

2'-Deoxyribonucleosides are important as building blocks for the synthesis of antisense drugs, antiviral nucleosides, and 2'-deoxyribonucleotides for polymerase chain reaction. The microbial production of 2'-deoxyribonucleosides from simple materials, glucose, acetaldehyde, and a nucleobase, through the reverse reactions of 2'-deoxyribonucleoside degradation and the glycolytic pathway, was investigated. The glycolytic pathway of baker's yeast yielded fructose 1,6-diphosphate from glucose using the energy of adenosine 5'-triphosphate generated from adenosine 5'-monophosphate through alcoholic fermentation with the yeast. Fructose 1,6-diphosphate was further transformed to 2-deoxyribose 5-phosphate in the presence of acetaldehyde by deoxyriboaldolase-expressing Escherichia coli cells via D-glyceraldehyde 3-phosphate. E. coli transformants expressing phosphopentomutase and nucleoside phosphorylase produced 2'-deoxyribonucleosides from 2-deoxyribose 5-phosphate and a nucleobase via 2-deoxyribose 1-phosphate through the reverse reactions of 2'-deoxyribonucleoside degradation. Coupling of the glycolytic pathway and deoxyriboaldolase-catalyzing reaction efficiently supplied 2-deoxyribose 5-phosphate, which is a key intermediate for 2'-deoxyribonucleoside synthesis. 2'-Deoxyinosine (9.9 mM) was produced from glucose, acetaldehyde, and adenine through three-step reactions via fructose 1,6-diphosphate and then 2-deoxyribose 5-phosphate, the molar yield as to glucose being 17.8%.


Assuntos
Acetaldeído/metabolismo , Adenina/metabolismo , Biotecnologia/métodos , Desoxirribonucleosídeos/metabolismo , Glucose/metabolismo , Ribosemonofosfatos/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Glicólise , Inosina/análogos & derivados , Inosina/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo
17.
Appl Environ Microbiol ; 69(7): 3791-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12839746

RESUMO

The gene encoding a deoxyriboaldolase (DERA) was cloned from the chromosomal DNA of Klebsiella pneumoniae B-4-4. This gene contains an open reading frame consisting of 780 nucleotides encoding 259 amino acid residues. The predicted amino acid sequence exhibited 94.6% homology with the sequence of DERA from Escherichia coli. The DERA of K. pneumoniae was expressed in recombinant E. coli cells, and the specific activity of the enzyme in the cell extract was as high as 2.5 U/mg, which was threefold higher than the specific activity in the K. pneumoniae cell extract. One of the E. coli transformants, 10B5/pTS8, which had a defect in alkaline phosphatase activity, was a good catalyst for 2-deoxyribose 5-phosphate (DR5P) synthesis from glyceraldehyde 3-phosphate and acetaldehyde. The E. coli cells produced DR5P from glucose and acetaldehyde in the presence of ATP. Under the optimal conditions, 100 mM DR5P was produced from 900 mM glucose, 200 mM acetaldehyde, and 100 mM ATP by the E. coli cells. The DR5P produced was further transformed to 2'-deoxyribonucleoside through coupling the enzymatic reactions of phosphopentomutase and nucleoside phosphorylase. These results indicated that production of 2'-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase is possible with the addition of a suitable energy source, such as ATP.


Assuntos
Acetaldeído/metabolismo , Aldeído Liases/metabolismo , Desoxirribonucleosídeos/biossíntese , Escherichia coli/enzimologia , Escherichia coli/genética , Glucose/metabolismo , Ribosemonofosfatos/biossíntese , Aldeído Liases/química , Aldeído Liases/genética , Sequência de Aminoácidos , Sequência de Bases , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Transformação Bacteriana
18.
Biosci Biotechnol Biochem ; 67(4): 933-6, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12784646

RESUMO

2-Deoxyribose 5-phosphate was produced from acetaldehyde and dihydroxyacetone phosphate via D-glyceraldehyde 3-phosphate by Klebsiella pneumoniae B-4-4 through deoxyriboaldolase- and triosephosphate isomerase-catalyzing reactions. Under the optimum conditions, 98.7 mM 2-deoxyribose 5-phosphate was produced from 200 mM acetaldehyde and 117 mM dihydroxyacetone phosphate in 2 h with a molar yield of 84%. The 2-deoxyriobse 5-phosphate produced was directly transformed to 2'-deoxyribonucleoside by phosphopentomutase- and nucleoside phosphorylase-catalyzing reactions.


Assuntos
Desoxirribonucleosídeos/biossíntese , Klebsiella pneumoniae/metabolismo , Ribosemonofosfatos/biossíntese , Acetaldeído/metabolismo , Pentosiltransferases/metabolismo , Fosfotransferases/metabolismo , Fosfatos Açúcares/metabolismo , Trioses/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...