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1.
J Biochem ; 142(5): 647-54, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17878218

RESUMO

The yjeA gene, encoding a secreted protein, YjeA, of Bacillus subtilis, was cloned and characterized. A derivative of YjeA, the recombinant YjeA-H, which contained a C-terminal His(6)-tag, was purified from Escherichia coli for functional studies. YjeA-H was shown to be an endonuclease, which hydrolyses both single-stranded and double-stranded DNA, but not RNA. Covalently closed circular pBR322 DNA incubated with YjeA-H was shown by gel electrophoresis to be first nicked to an open circular form, and then to a linearized structure on a background of DNA smear, and finally to small species of linear molecules that accumulated gradually. When (32)P-labelled pBR322 DNA was used as substrate, YjeA-H was shown to progressively nick both DNA strands in a random fashion, creating intermediates of various structures, as well as DNA smears comprising linear molecules of different sizes. The final products were found to consist essentially of degraded species of DNA. The detection of a putative signal peptide at the N-terminus of YjeA, together with the purification of YjeA-H from the culture supernatants of E. coli yjeA-H clones, and the identification of YjeA in the culture medium of Bacillus subtilis, supports the conclusion that YjeA is a secretory protein of Bacillus subtilis.


Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias , Desoxirribonucleases/genética , Proteínas de Escherichia coli/genética , Genes Bacterianos/genética , Sequência de Aminoácidos , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Desoxirribonucleases/metabolismo , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Hidrólise , Dados de Sequência Molecular , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Especificidade por Substrato
3.
Diabetes Care ; 26(6): 1856-61, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12766123

RESUMO

OBJECTIVE: To study the healing effect of recombinant human epidermal growth factor (hEGF) on diabetic foot ulcers. RESEARCH DESIGN AND METHODS: A total of 127 consecutive patients were screened and 61 diabetic subjects were recruited into this double-blind randomized controlled study. Predetermined criteria were used for diagnosis and classification of the diabetic wound. The patients were randomized into three groups. All patients attended our Diabetes Ambulatory Care Center every other week for joint consultation with the diabetologist and the podiatrist. Group 1 (control) was treated with Actovegin 5% cream (Actovegin), group 2 with Actovegin plus 0.02% (wt/wt) hEGF, and group 3 with Actovegin plus 0.04% (wt/wt) hEGF. The study end point was the complete closure of the wound. Failure to heal was arbitrarily defined as incomplete healing after 12 weeks. RESULTS: Final data were obtained from 61 patients randomly assigned into three groups. The mean ages of the patients, wound sizes, wound duration, metabolic measurements, and comorbidities were comparable within groups, except that group 3 had more female patients. Mean follow-up for the patients was 24 weeks. Data were cutoff at 12 weeks, and results were analyzed by intention to treat. After 12 weeks, in group 1 (control) eight patients had complete healing, two patients underwent toe amputation, and nine had nonhealing ulcers. In group 2 (0.02% [wt/wt] hEGF) 12 patients experienced wound healing, 2 had toe amputations, and 7 had nonhealing ulcers. Some 20 of 21 patients in group 3 (0.04% [wt/wt] hEGF) showed complete wound healing. Healing rates were 42.10, 57.14, and 95% for the control, 0.02% (wt/wt) hEGF, and 0.04% (wt/wt) hEGF groups, respectively. Kaplan-Meier survival analysis suggested that application of cream with 0.04% (wt/wt) hEGF caused more ulcers to heal by 12 weeks and increased the rate of healing compared with the other treatments (log-rank test, P = 0.0003). CONCLUSIONS: Our data support the contention that application of hEGF-containing cream, in addition to good foot care from a multidisciplinary team, significantly enhances diabetic foot ulcer wound healing and reduces the healing time.


Assuntos
Pé Diabético/tratamento farmacológico , Fator de Crescimento Epidérmico/uso terapêutico , Cicatrização/efeitos dos fármacos , Idade de Início , Idoso , Método Duplo-Cego , Feminino , Úlcera do Pé/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Proteínas Recombinantes/uso terapêutico , Fatores de Tempo
4.
Protein Expr Purif ; 29(1): 51-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12729725

RESUMO

Manduca diuresin (MD), a 30 amino acid peptide isolated from the tobacco hornworm Manduca sexta, was found to play an important role in the regulation of water and salt balance in the insect. To facilitate studies relating to the function and structure of MD, a synthetic gene encoding MD was assembled and expressed in Escherichia coli. Using an excretion vector, expression of the MD gene in an induced transformant was detected at the transcriptional and translational levels by Northern-blot and ELISA analyses, respectively. With the use of glutathione-S-transferase as the reporter protein, MD was confirmed to be expressed in E. coli. The recombinant product was resolved by reverse-phase HPLC into three peptide groups of different retention times, which were shown by mass spectrometry to be composed of MD deletants missing various lengths of the C-terminus. Despite the deletions and the absence of an amidated C-terminus, the deletants were shown to be biologically active, suggesting the importance of the N-terminus of MD for biological activity.


Assuntos
Escherichia coli/metabolismo , Peptídeos/química , Peptídeos/isolamento & purificação , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , DNA/metabolismo , Ensaio de Imunoadsorção Enzimática , Glutationa Transferase/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Manduca , Modelos Genéticos , Dados de Sequência Molecular , Oligonucleotídeos/química , Peptídeos/metabolismo , Biossíntese de Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Transcrição Gênica
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