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1.
BJOG ; 120(13): 1685-94; discussion 1944-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23937774

RESUMO

OBJECTIVE: To analyse life-threatening obstetric complications that occurred in public hospitals in Argentina. DESIGN: Multicentre collaborative cross-sectional study. SETTING: Twenty-five hospitals included in the Perinatal Network of Buenos Aires Metropolitan Area. POPULATION: Women giving birth in participating hospitals during a 1-year period. METHODS: All cases of severe maternal morbidity (SMM) and maternal mortality (MM) during pregnancy (including miscarriage and induced abortion), labour and puerperium were included. Data were collected prospectively. MAIN OUTCOME MEASURES: Identification criteria, main causes and incidence of SMM; case-fatality rates, morbidity-mortality index and effective intervention's use rate. RESULTS: A total of 552 women with life-threatening conditions were identified: 518 with SMM, 34 with MM. Identification criteria for SMM were case-management (48.9%), organ dysfunction (15.2%) and mixed criteria (35.9%). Incidence of SMM was 0.8% (95% confidence interval [95% CI] 0.73-0.87%) and hospital maternal death ratio was 52.3 per 100 000 live births (95% CI 35.5-69.1). Main causes of MM were abortion complications and puerperal sepsis; main causes of SMM were postpartum haemorrhage and hypertension. Overall case-fatality rate was 6.2% (95% CI 4.4-8.6): the highest due to sepsis (14.8%) and abortion complications (13.3%). Morbidity-mortality index was 15:1 (95% CI 7.5-30.8). Use rate of known effective interventions to prevent or treat main causes of MM and SMM was 52.3% (95% CI 46.9-57.7). CONCLUSIONS: This study describes the importance of life-threatening obstetric complications that took place in public hospitals with comprehensive obstetric care and the low utilisation of known effective interventions that may decrease rates of SMM and MM. It also provides arguments that justify the need to develop a surveillance system for SMM.


Assuntos
Mortalidade Materna , Complicações na Gravidez/epidemiologia , Transtornos Puerperais/epidemiologia , Aborto Incompleto/terapia , Aborto Induzido/efeitos adversos , Aborto Induzido/mortalidade , Adulto , Antibioticoprofilaxia , Anticonvulsivantes/uso terapêutico , Argentina , Estudos Transversais , Feminino , Hospitais Públicos , Humanos , Sulfato de Magnésio/uso terapêutico , Gravidez , Estudos Prospectivos , Sepse/mortalidade , Curetagem a Vácuo , Adulto Jovem
2.
Proc Natl Acad Sci U S A ; 105(48): 18964-9, 2008 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-19033196

RESUMO

Following birth, the breast-fed infant gastrointestinal tract is rapidly colonized by a microbial consortium often dominated by bifidobacteria. Accordingly, the complete genome sequence of Bifidobacterium longum subsp. infantis ATCC15697 reflects a competitive nutrient-utilization strategy targeting milk-borne molecules which lack a nutritive value to the neonate. Several chromosomal loci reflect potential adaptation to the infant host including a 43 kbp cluster encoding catabolic genes, extracellular solute binding proteins and permeases predicted to be active on milk oligosaccharides. An examination of in vivo metabolism has detected the hallmarks of milk oligosaccharide utilization via the central fermentative pathway using metabolomic and proteomic approaches. Finally, conservation of gene clusters in multiple isolates corroborates the genomic mechanism underlying milk utilization for this infant-associated phylotype.


Assuntos
Bifidobacterium/genética , Trato Gastrointestinal/microbiologia , Leite Humano , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bifidobacterium/metabolismo , Aleitamento Materno , Feminino , Genoma Bacteriano , Humanos , Recém-Nascido , Leite Humano/química , Leite Humano/metabolismo , Dados de Sequência Molecular , Família Multigênica , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Filogenia , Gravidez
3.
J Bacteriol ; 192(24): 6497-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20952571

RESUMO

Methylosinus trichosporium OB3b (for "oddball" strain 3b) is an obligate aerobic methane-oxidizing alphaproteobacterium that was originally isolated in 1970 by Roger Whittenbury and colleagues. This strain has since been used extensively to elucidate the structure and function of several key enzymes of methane oxidation, including both particulate and soluble methane monooxygenase (sMMO) and the extracellular copper chelator methanobactin. In particular, the catalytic properties of soluble methane monooxygenase from M. trichosporium OB3b have been well characterized in context with biodegradation of recalcitrant hydrocarbons, such as trichloroethylene. The sequence of the M. trichosporium OB3b genome is the first reported from a member of the Methylocystaceae family in the order Rhizobiales.


Assuntos
Genoma Bacteriano , Methylosinus trichosporium/classificação , Methylosinus trichosporium/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Dados de Sequência Molecular
4.
Appl Environ Microbiol ; 75(9): 2841-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19270133

RESUMO

Organisms of the candidate phylum termite group 1 (TG1) are regularly encountered in termite hindguts but are present also in many other habitats. Here, we report the complete genome sequence (1.64 Mbp) of "Elusimicrobium minutum" strain Pei191(T), the first cultured representative of the TG1 phylum. We reconstructed the metabolism of this strictly anaerobic bacterium isolated from a beetle larva gut, and we discuss the findings in light of physiological data. E. minutum has all genes required for uptake and fermentation of sugars via the Embden-Meyerhof pathway, including several hydrogenases, and an unusual peptide degradation pathway comprising transamination reactions and leading to the formation of alanine, which is excreted in substantial amounts. The presence of genes encoding lipopolysaccharide biosynthesis and the presence of a pathway for peptidoglycan formation are consistent with ultrastructural evidence of a gram-negative cell envelope. Even though electron micrographs showed no cell appendages, the genome encodes many genes putatively involved in pilus assembly. We assigned some to a type II secretion system, but the function of 60 pilE-like genes remains unknown. Numerous genes with hypothetical functions, e.g., polyketide synthesis, nonribosomal peptide synthesis, antibiotic transport, and oxygen stress protection, indicate the presence of hitherto undiscovered physiological traits. Comparative analysis of 22 concatenated single-copy marker genes corroborated the status of "Elusimicrobia" (formerly TG1) as a separate phylum in the bacterial domain, which was so far based only on 16S rRNA sequence analysis.


Assuntos
Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Isópteros/microbiologia , Animais , Trato Gastrointestinal/microbiologia , Ordem dos Genes , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
5.
Dalton Trans ; 45(30): 12006-14, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27389315

RESUMO

Novel nanohybrid materials were prepared by immobilizing Co nanoparticles on a microporous framework MIL-53(Al) as a porous host matrix. The synthesized cobalt-containing materials were characterized by XRD, STEM, and oxygen titration. The catalytic performance of Co@MIL-53(Al) nanohybrids was examined in Fischer-Tropsch synthesis (FTS) for the first time. A higher selectivity to C5+ hydrocarbons and lower selectivity to methane for Co@MIL-53(Al) as compared to conventional Co/Al2O3 were observed.

6.
Genome Announc ; 4(6)2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27811105

RESUMO

Alkaliphilus metalliredigens strain QYMF is an anaerobic, alkaliphilic, and metal-reducing bacterium associated with phylum Firmicutes QYMF was isolated from alkaline borax leachate ponds. The genome sequence will help elucidate the role of metal-reducing microorganisms under alkaline environments, a capability that is not commonly observed in metal respiring-microorganisms.

7.
Genome Announc ; 3(1)2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25614562

RESUMO

We report the genome sequence of Anaeromyxobacter sp. Fw109-5, isolated from nitrate- and uranium-contaminated subsurface sediment of the Oak Ridge Integrated Field-Scale Subsurface Research Challenge (IFC) site, Oak Ridge Reservation, TN. The bacterium's genome sequence will elucidate its physiological potential in subsurface sediments undergoing in situ uranium bioremediation and natural attenuation.

8.
Hypertension ; 19(2 Suppl): II132-6, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1735567

RESUMO

The antihypertensive effect, tolerability, and influence on placental and fetal circulation of cadralazine, a 6-substituted derivative of 3-hydrazinopyridoxine structurally related to hydralazine, was assessed in 46 preeclamptic patients in the third trimester of pregnancy and with diastolic blood pressure of 100-120 mm Hg after 24 hours of bed rest. Patients who fulfilled the inclusion criteria at the initial report (24-48-hour run-in period after hospitalization) entered the titration period. During titration, cadralazine was administered at an initial dose of 5 mg once a day; if after 3 days diastolic blood pressure was still above 90 mm Hg, 5 mg more was added for another 3 days, and so forth, until the maximum dose (20 mg once a day) was reached. Patients who did not lower diastolic blood pressure below 90 mm Hg were considered nonresponders; those who achieved the desired diastolic level (responders) entered the maintenance period, which lasted until delivery. Eight patients delivered during the titration period (premature discontinuation group). A significant decrease in systolic and diastolic blood pressures was observed between the initial report and the titration period. During titration, there were 27 responders (71%) and 11 nonresponders. One of the responders was lost to follow-up. Cadralazine proved to be effective in lowering blood pressure levels; in the group of responders, a mean diastolic reduction of 20% was observed. This significant decrease was not affected by the diastolic blood pressure increase observed at the end of gestation. No adverse effects from the drug were observed on fetal development or immediate postnatal adaptation to stress during labor, and only mild maternal side effects were detected (headache).


Assuntos
Anti-Hipertensivos/uso terapêutico , Pré-Eclâmpsia/tratamento farmacológico , Piridazinas/uso terapêutico , Adulto , Anti-Hipertensivos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Feminino , Feto/irrigação sanguínea , Frequência Cardíaca/efeitos dos fármacos , Humanos , Projetos Piloto , Placenta/irrigação sanguínea , Gravidez , Piridazinas/administração & dosagem , Fluxo Sanguíneo Regional/efeitos dos fármacos
9.
Gene ; 97(2): 259-66, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1999290

RESUMO

A new dual-replicon recombinant plasmid, pPR53-tsr, has been constructed; it is a derivative of the expression vector pPR-TGATG-1 [Mashko et al., Gene 88 (1990) 121-126]. In contrast to its progenitor, pPR53-tsr is a low-copy-number (low-Cop) plasmid amplifiable in temperature-dependent fashion. In addition to both the replicon and the par locus from plasmid pSC101, providing segregational stability and a low Cop at 28 degrees C, the new plasmid contains a mutant ColE1 replicon whose RNAII is synthesized under the control of the pL promoter. The presence of a thermolabile repressor, cIts857, allows the thermo-inducible amplification of pPR53-tsr; the increased plasmid Cop is estimated at approx. 200 per genome 6 h after thermal induction at 42 degrees C. Thus, pPR53-tsr can be used as a donor of the thermo-inducible dual-replicon fragment for recombinant plasmids. Here, we employ such an approach for optimization of production of human interleukin-1 beta (hIL-1 beta) in Escherichia coli at a high level. The thermo-induced level of recombinant hIL-1 beta (re-hIL-1 beta) biosynthesis was around 9% of total cellular protein when the dual-replicon high-Cop vector was used. A method based on acidification of the water-soluble protein fraction to pH 4.0 has been developed that allows for the isolation of 80%-pure re-hIL-1 beta. The homogeneous material was obtained by two subsequent hydrophobic sorbent chromatographies. The protein yield ranged between 3-5 mg of re-hIL-1 beta/g of wet cells. The re-hIL-1 beta specific activity was about 2 x 10(8) units/mg, coinciding with that of the authentic hIL-1 beta.


Assuntos
Escherichia coli/genética , Expressão Gênica , Interleucina-1/genética , Replicon , Sequência de Bases , Clonagem Molecular , Replicação do DNA , Eletroforese em Gel de Poliacrilamida , Humanos , Interleucina-1/biossíntese , Dados de Sequência Molecular , Plasmídeos , Regiões Promotoras Genéticas , Mapeamento por Restrição , Temperatura
10.
Gene ; 88(1): 121-6, 1990 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-2187746

RESUMO

A TGATG vector system was developed that allows for the construction of hybrid operons with partially overlapping genes, employing the effects of translational coupling to optimize expression of cloned cistrons in Escherichia coli. In this vector system (plasmid pPR-TGATG-1), the coding region of a foreign gene is attached to the ATG codon situated on the vector, to form the hybrid operon transcribed from the phage lambda PR promoter. The cloned gene is the distal cistron of this hybrid operon ('overlappon'). The efficiently translated cro'-cat'-'trpE hybrid cistron is proximal to the promoter. The coding region of this artificial fused cistron [the length of the corresponding open reading frame is about 120 amino acids (aa)] includes the following: the N-terminal portions of phage lambda Cro protein (20 aa), the CAT protein of E. coli (72 aa) and 3' C-terminal codons of the E. coli trpE gene product. At the 3'-end of the cro'-cat'-'trpE fused cistron there is a region for efficient translation reinitiation: a Shine-Dalgarno sequence of the E. coli trpD gene and the overlapping stop and start codons (TGATG). In this sequence, the last G is the first nucleotide of the unique SacI-recognition site (GAGCT decreases C) and so integration of the structural part of the foreign gene into the vector plasmid may be performed using blunt-end DNA linking after the treatment of pPR-TGATG-1 with SacI and E. coli DNA polymerase I or its Klenow fragment.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Vetores Genéticos , Sequência de Bases , Clonagem Molecular , DNA Recombinante/análise , Genes Bacterianos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Mapeamento por Restrição
11.
Int J Radiat Oncol Biol Phys ; 10(10): 1975-85, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6490426

RESUMO

We have developed a general purpose, comprehensive, and highly reliable computerized Record and Verify System to detect and prevent mistakes in the delivery of external beam radiation therapy. This system helps prevent accidental delivery of dangerous dose, improves quality control, and provides invaluable record keeping and report generating capabilities. Currently, treatment machine and couch parameter settings of four different machines are monitored by the system and compared with prescribed values. The system inhibits a machine from being turned on if the settings do not agree with the prescribed values to within specified maximum permissible deviations. The system is user-friendly and provides useful, complete, and easily accessible data. We describe many aspects of the system including hardware, software, data, and operation, and we conclude with a brief discussion of clinical experience and preliminary data.


Assuntos
Computadores , Sistemas de Informação , Radioterapia , Registros , Humanos , Neoplasias/radioterapia
12.
Inflamm Bowel Dis ; 4(2): 89-94, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9589295

RESUMO

Patients with Crohn's disease (CD) have an increased risk of developing gallstones, but the mechanisms are unknown. In a previous study, we found a subnormal cholesterol saturation in the bile of patients with short ileal resections due to CD. The aim of this study was to test the hypothesis that (a) CD patients with a long ileal resection have an altered biliary composition and (b) that CD patients with short or long ileal resection have an increased content of bilirubin in their bile. Biliary lipid composition, cholesterol saturation, bile acid pattern, and bilirubin concentration were determined in fasting duodenal bile of 10 CD patients with long ileal resections and in 4 patients with short resections. Ten healthy subjects served as controls. Cholesterol saturation was significantly lower in those CD patients who had a long or short resection compared with the healthy subjects. Bile acid composition in the CD patients was characterized by a significant decrease in the deoxycholic acid fraction and a prominent increase in the ursodeoxycholic acid fraction. The bilirubin concentrations, expressed as micromoles of bilirubin per millimole bile acid, were 45-50% higher in patients who had a long or a short ileal resection compared with healthy controls. Based on these results, CD patients who had had an ileal resection seem not to be at an increased risk of cholesterol gallstone formation but rather at risk of developing pigment stones.


Assuntos
Bile/química , Colelitíase/cirurgia , Doença de Crohn/cirurgia , Adulto , Bilirrubina/análise , Colelitíase/etiologia , Colesterol/metabolismo , Doença de Crohn/complicações , Feminino , Humanos , Ileíte/complicações , Ileíte/cirurgia , Masculino , Pessoa de Meia-Idade , Probabilidade , Valores de Referência , Fatores de Risco
13.
Photosynth Res ; 70(1): 43-52, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-16228361

RESUMO

The genome of Rhodobacter capsulatus has been completely sequenced. It consists of a single chromosome containing 3.5 Mb and a circular plasmid of 134 kb. This effort, started in 1992, began with a fine-structure restriction map of an overlapping set of cosmids that covered the genome. Cosmid sequencing led to a gapped genome that was filled by primer walking on the chromosome and by using lambda clones. Methods had to be developed to handle strong stops in the high GC (68%) inserts. Annotation was done with the ERGO system at Integrated Genomics, as was the reconstruction of the cell's metabolism. It was possible to recognize 3709 orfs of which functional assignments could be made with high confidence to 2392 (65%). Unusual features include the presence of numerous cryptic phage genomes embedded in the chromosome.

14.
Aliment Pharmacol Ther ; 13(10): 1323-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10540047

RESUMO

BACKGROUND: Heparin given intravenously has shown beneficial effects in the treatment of refractory ulcerative colitis in open trials. Low molecular weight heparin (LMWH) offers advantages in the method of administration but have not been evaluated in inflammatory bowel disease conditions. AIM: To assess the tolerability and safety of subcutaneous self-administered LMWH in outpatients with refractory ulcerative colitis and to evaluate any potential adjuvant therapeutic effect. PATIENTS AND METHODS: Twelve patients with mild to moderately active ulcerative colitis were included in the trial. The patients had either responded poorly to treatment with conventional therapy, including oral and/or rectal glucocorticosteroids, or had experienced a rapid relapse during or shortly after GCS therapy. Dalteparin sodium 5000 units s.c. injection was administered twice daily for 12 weeks. Patients were monitored for possible adverse events and changes in clinical symptoms, and endoscopic and histological scores were analysed. Leucocyte scanning was performed at inclusion and at the end of the study. RESULTS: Tolerability and compliance were excellent and no serious adverse events occurred. Eleven patients improved symptomatically and six (50%) attained complete remission after 12 weeks of treatment. Endoscopic, scintigraphic and histological scores were found to be significantly improved. CONCLUSION: Self-administered LMWH given s.c. may be a safe adjuvant therapy for patients with active, glucocorticosteroids-refractory ulcerative colitis. A controlled trial should be undertaken to confirm the positive effects found in this study.


Assuntos
Anticoagulantes/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Heparina de Baixo Peso Molecular/uso terapêutico , Adulto , Idoso , Anticoagulantes/efeitos adversos , Quimioterapia Adjuvante , Colite Ulcerativa/diagnóstico por imagem , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Heparina de Baixo Peso Molecular/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Exametazima
15.
Mol Biol (Mosk) ; 21(5): 1297-309, 1987.
Artigo em Russo | MEDLINE | ID: mdl-3316974

RESUMO

A new method of optimization of foreign gene expression in E. coli, based on the construction of hybrid operons with partially overlapping genes is described. The partial overlapping of the translation termination and initiation sites in the formed operon must provide translational coupling of appropriate gene product synthesis. Such an approach has provided the synthesis of human interferon alpha F in E. coli cells under the control of the lacUV5-promotor up to about (3-4).10(7) units per liter of bacterial culture. The reinitiation of the distal gene translation is shown to take place in the intercistronic region. Substitution of the lacUV5 promotor by the more efficient tac one allowed to increase the synthesis level of interferon alpha F to (1-2).10(8) units per liter. The conclusion is made about the equimolarity of distal and proximal to the promotor genes products syntheses when the intercistronic region of E. coli trpE-trpD genes are used for translational coupling.


Assuntos
Escherichia coli/genética , Regulação da Expressão Gênica , Engenharia Genética , Interferon Tipo I/genética , Óperon , Sequência de Bases , Humanos , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Plasmídeos , Biossíntese de Proteínas
16.
Mol Biol (Mosk) ; 22(4): 1033-44, 1988.
Artigo em Russo | MEDLINE | ID: mdl-3054501

RESUMO

The study on the rate of initiation of model gene cat transcription under the control of E. coli (Plac UV5, Ptrp, Pcat, Ptac), phage lambda (PL, PR), phi X174 (PD) promotors was carried out by means of hybridization of pulse labelled in vivo mRNA with the DNA coding parts. The presence of gene bla(Apr) with its own constitutive promoter in all the recombinants permitted to use the level of appropriate mRNA in the cell as an internal standard. This method allowed to evaluate the true efficiency of the promoters in question. The strength of the promoters studied is shown to be equal within the limit of one order value.


Assuntos
Cloranfenicol O-Acetiltransferase/genética , Colífagos/genética , Escherichia coli/genética , Regulação da Expressão Gênica , Genes Reguladores , Regiões Promotoras Genéticas , Sequência de Bases , Clonagem Molecular , Escherichia coli/enzimologia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Plasmídeos , Recombinação Genética
17.
Mol Biol (Mosk) ; 21(1): 73-86, 1987.
Artigo em Russo | MEDLINE | ID: mdl-2437441

RESUMO

The trpOP, lacUV5, tacOP, PR and PL-promotors were cloned in the previously obtained pML4 vector plasmid. The expression of structural gene cat was studied by the chloramphenicolacetyltransferase determination in cell extracts. The level of protein synthesis by appropriate recombinant plasmids was analysed in vivo and in vitro. It was shown that the efficiency of the gene expression is determined by both the "strength" of the promotors and mRNA translation specificity. The obtained collection of the plasmids might be used for the determination of the promotor strength by the hybridization of pulse-labeled mRNA with DNA and an effective expression of the genes by means of "hybrid protein gene" and "hybrid operon" constructions.


Assuntos
Acetiltransferases/genética , Clonagem Molecular , Escherichia coli/genética , Regulação da Expressão Gênica , Genes , Regiões Promotoras Genéticas , Acetiltransferases/metabolismo , Bacteriófago lambda/genética , Cloranfenicol O-Acetiltransferase , DNA Recombinante , Escherichia coli/enzimologia , Cinética , Conformação de Ácido Nucleico , Plasmídeos , RNA Bacteriano/genética , RNA Mensageiro/genética
18.
Mol Biol (Mosk) ; 21(5): 1310-21, 1987.
Artigo em Russo | MEDLINE | ID: mdl-2960884

RESUMO

The possibility of creating artificial overlappons was studied on the model of two genes, that coding for the N-terminal part of lambda cro protein and the cat of E. coli. To test the dependence of translational coupling efficiency on the intercistronic region a series of recombinant DNA molecules carrying different hybrid operons with partially overlapping genes was constructed. The translational efficiency of the distal to the promoter gene was shown to depend on the intercistronic region structure: overlapping of the AUG codon with the terminating one of the proximal gene in the UGAUG manner is optimal for the translational coupling, and the displacement of AUG at several nucleotides in both directions decreases the translational reinitiation efficiency for the ribosomes, that have synthesised the first gene product.


Assuntos
Proteínas de Ligação a DNA , Óperon , Biossíntese de Proteínas , Recombinação Genética , Acetiltransferases/genética , Bacteriófago lambda/genética , Cloranfenicol O-Acetiltransferase , Códon , Escherichia coli/genética , Hibridização de Ácido Nucleico , Plasmídeos , Proteínas Repressoras/genética , Proteínas Virais , Proteínas Virais Reguladoras e Acessórias
19.
Mol Biol (Mosk) ; 25(5): 1273-84, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1753956

RESUMO

The use of the polymerase chain reaction was proposed for intron excision from genomic genes with known nucleotide sequences. Three exons (5, 6 and 7) of genomic interleukin 1 beta gene were amplified by means of thermostable DNA polymerase TthI from Thermus thermophilus on the base of cloned in M13 phage human genomic interleukin 1 beta gene. Synthetic oligonucleotides complementary to sequences flanking exons were used as primers. The fragments obtained by exon DNA amplification were joined in the correct order due to reciprocal complementation of end sequences, that was foreseen during synthesis of oligonucleotide primers followed by amplification of the enlarged fragments. As a result the structural interleukin-1 beta gene consisting of three exons was assembled. DNA sequences carrying the ATG initiation codon and XbaI recognition site at the 5'-end, and PstI recognition site at the 3'-end (essential for insertion into the expression vector) were formed by the additional end sequences of primers. The nucleotide sequence analysis of the obtained structural gene revealed its complete identity with natural interleukin 1 beta human gene. We created the expression vector pPR114 with phage lambda promoter PR thermo-inducible in case of the cIts857 repressor presence in cells. It was used for expression of the present gene. The interleukin 1 beta synthesized in E. coli had biological activity.


Assuntos
DNA/genética , Escherichia coli/genética , Amplificação de Genes , Expressão Gênica , Interleucina-1/genética , Íntrons , Bacteriófagos/genética , Sequência de Bases , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Genes Bacterianos , Genes Virais , Vetores Genéticos , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
20.
Mol Gen Mikrobiol Virusol ; (8): 36-41, 1987 Aug.
Artigo em Russo | MEDLINE | ID: mdl-3119998

RESUMO

The expression of human leucocyte interferon alpha F gene in plasmid pLM-IFN alpha F-273 is controlled by a hybrid tac (trp-lac) promoter. A structural gene for interferon alpha F is a component of the hybrid operon lacZ'-IFN alpha F-TcR, that contains an E. coli trp-operon intercystronic region. Plasmid pLM IFN alpha F-273--directed interferon synthesis allows to obtain about 10(7) IU/l. This plasmid was cloned in broad-host-range vector plasmid pAYC31. The hybrid bi-repliconed plasmid containing interferon gene as well as its single-repliconed deletion derivatives obtained by the in vivo recombination, were introduced into obligate methylotroph Methylobacillus flagellatum KT and Pseudomonas putida PpG6. Methylotrophic strain and Pseudomonas were able to transcribe the interferon gene from E. coli tac promoter, the yield of interferon being 2-4-fold higher as compared with the one in the initial host.


Assuntos
Clonagem Molecular , Interferon Tipo I/genética , Methylococcaceae/genética , Pseudomonas/genética , Vetores Genéticos , Humanos , Plasmídeos
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