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1.
Benef Microbes ; : 1-14, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37128181

RESUMEN

Previously, we demonstrated that post-immunobiotics derived from Lactobacillus gasseri TMT36, TMT39, and TMT40 strains (HK36, HK39 and HK40, respectively) differentially regulated Toll-like receptor 3 (TLR3)-mediated antiviral respiratory immunity in infant mice. In this work, we investigated whether the HK36, HK39 and HK40 nasal treatments were able to improve the resistance against primary respiratory syncytial virus (RSV) infection and secondary pneumococcal pneumonia. Our results demonstrated that the three treatments increased the resistance to primary viral infection by reducing variations in body weight, RSV titers and lung damage of infected infant mice. Post-immunobiotics significantly enhanced the expressions of interferon (IFN)-λ, IFN-ß, IFN-γ, interleukin(IL) - 1ß, IL-6, IL-27, Mx1, RNAseL and 2'-5'-oligoadenylate synthetase 1 (OAS1) genes and decreased tumour necrosis factor (TNF)-α in alveolar macrophages of RSV-challenged mice. In addition, the studies in the model of RSV-Streptococcus pneumoniae superinfection showed that the HK39 and HK40 treatments were capable of reducing lung damage, lung bacterial cell counts, and the dissemination of S. pneumoniae into the blood of infant mice. The protective effect was associated with increases in IFN-ß, IFN-γ, IL-10, and IL-27 in the respiratory tract. This study demonstrates that the nasal application of the post-immunobiotics HK39 and HK40 stimulates innate respiratory immunity and enhances the defences against primary RSV infection and secondary pneumococcal pneumonia offering an alternative to combat respiratory superinfections in children, which can be fatal.

2.
Benef Microbes ; 13(1): 61-72, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35098908

RESUMEN

Lactobacillus delbrueckii subsp. delbrueckii TUA4408L has the ability to grow and ferment soymilk and is able to modulate the innate immune response of intestinal epithelial cells in vitro. These two properties prompt us to evaluate whether the soymilk fermented with the TUA4408L strain can induce beneficial immunomodulatory effects in vivo. For this purpose, pigs were selected as a preclinical model. The studies performed here demonstrated that the L. delbrueckii subsp. delbrueckii TUA4408L-fermented soymilk (TUA4408L FSM) reduced blood markers of inflammation and differentially regulated the expression of inflammatory and regulatory cytokines in the intestinal mucosa. These immunological changes induced by the TUA4408L FSM were associated to an enhanced resistance to pathogenic Escherichia coli and an improved grow performance and meat quality of pigs. The experiments and analysis in our study indicate that the immunobiotic TUA4408L FSM could be an interesting non-dairy functional food to beneficially modulate the intestinal immune system, improve protection against pathogens and reduce inflammatory damage. The preclinical study carried out here in pigs could have a better correlation in humans, compared to a rodent model. However, the clinical relevance of these findings still needs to be confirmed by further research, for example, in controlled human challenge studies.


Asunto(s)
Lactobacillus delbrueckii , Probióticos , Leche de Soja , Animales , Lactobacillus , Lactobacillus delbrueckii/metabolismo , Probióticos/metabolismo , Probióticos/farmacología , Porcinos
3.
Eur J Neurol ; 18(11): 1299-303, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21435111

RESUMEN

BACKGROUND AND PURPOSES: Excessive daytime sleepiness (EDS) is a common sleep disorder in patients with Parkinson disease (PD). Non-ergot dopamine agonists increase the risk of unanticipated sleep episodes. OBJECTIVE: We aimed to assess the influence of renal function on EDS in patients with PD. METHODS: Sixty-two patients treated with ropinirole or pramipexole were recruited for this study. We evaluated the historical and clinical characteristics including the motor symptom rating scales, Epworth Sleepiness Scale (ESS), and estimated glomerular filtration rate (eGFR). An ESS score of 10 or greater was defined as EDS. Participants with eGFR < 60 ml/min/1.73 m(2) were determined to have chronic kidney disease (CKD). Multiple logistic regression analysis was performed to determine the predictive factors of EDS. RESULTS: Chronic kidney disease was found to be a significant predictive factor for EDS in all patients (P = 0.014). We observed a negative correlation between the severity of daytime sleepiness and renal function in patients treated with pramipexole alone (r(s) = -0.637, P < 0.001). CONCLUSIONS: Chronic kidney disease may be a risk factor for EDS, especially in patients treated with pramipexole, which is directly excreted in the urine.


Asunto(s)
Trastornos de Somnolencia Excesiva/epidemiología , Enfermedades Renales/complicaciones , Enfermedades Renales/epidemiología , Enfermedad de Parkinson/complicaciones , Anciano , Benzotiazoles/efectos adversos , Benzotiazoles/agonistas , Benzotiazoles/farmacocinética , Comorbilidad/tendencias , Trastornos de Somnolencia Excesiva/psicología , Agonistas de Dopamina/efectos adversos , Agonistas de Dopamina/farmacocinética , Femenino , Humanos , Indoles/efectos adversos , Indoles/agonistas , Indoles/farmacocinética , Enfermedades Renales/psicología , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/fisiopatología , Pramipexol
5.
Science ; 168(3938): 1477-8, 1970 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-5445941

RESUMEN

Exposure of normal human skin in vivo to ultraviolet irradiation at wavelengths shorter than 320 nanometers stimtulated an unscheduled DNA synthesis in all of the cell layers of the epidermis and in the upper dermnial fibrocytes. The skin of patients with xeroderma pigmentosum did not show this response. correlation of these findings with previous tissue culture studies suggests that the defect in repair of the damaged DNA in xeroderma cells occurs in vivo as well as in vitro.


Asunto(s)
ADN/biosíntesis , Piel/metabolismo , Xerodermia Pigmentosa/metabolismo , Autorradiografía , Humanos , Genética de Radiación , Piel/efectos de la radiación , Timidina/metabolismo , Tritio , Rayos Ultravioleta
6.
Genes Immun ; 9(4): 302-8, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18418398

RESUMEN

T-box transcription factor, T-bet, has a central role in the differentiation of T-helper (Th) progenitor cells to Th1 or Th2 effector cells, partly by regulating the expression of genes such as interferon-gamma (IFN-gamma). However, the direct target genes, especially those mediating the transcriptional network initiated by T-bet, are not yet fully understood. By combining chromatin immunoprecipitation from Th1 cells with human cytosine-phosphate-guanine-island array analysis, Onecut 2 (OC2), which encodes a member of the ONECUT class of transcriptional activators, was identified as a direct target gene of T-bet. OC2 is expressed in Th1 but not Th2 cells and reporter assays showed that T-bet transactivates OC2 transcription through putative T-bet half-sites locating -451 to -347 of OC2 promoter region. Moreover, we found that OC2 binds and transactivates human T-bet promoter. These results suggest that not only cell-extrinsic regulation via the IFN-gamma/STAT1 pathway, but also cell-intrinsic transcriptional positive feedback loop between T-bet and OC2 could be involved in Th1 development.


Asunto(s)
Proteínas de Homeodominio/genética , Proteínas de Dominio T Box/genética , Células TH1/inmunología , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Sitios de Unión , Células COS , Chlorocebus aethiops , Inmunoprecipitación de Cromatina , Secuencia de Consenso , Islas de CpG/genética , Genes Reporteros , Hemaglutininas/metabolismo , Proteínas de Homeodominio/química , Proteínas de Homeodominio/metabolismo , Humanos , Luciferasas de Renilla/metabolismo , Datos de Secuencia Molecular , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas , Unión Proteica , Estructura Terciaria de Proteína , Proteínas de Dominio T Box/metabolismo , Células TH1/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Activación Transcripcional
7.
Nucleic Acids Res ; 29(22): 4617-24, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11713311

RESUMEN

A recJ homolog was cloned from the extremely thermophilic bacterium Thermus themophilus HB8. It encodes a 527 amino acid protein that has 33% identity to Escherichia coli RecJ protein and includes the characteristic motifs conserved among RecJ homologs. Although T.thermophilus RecJ protein (ttRecJ) was expressed as an inclusion body, it was purified in soluble form through denaturation with urea and subsequent refolding steps. Limited proteolysis showed that ttRecJ has a protease-resistant core domain, which includes all the conserved motifs. We constructed a truncated ttRecJ gene that corresponds to the core domain (cd-ttRecJ). cd-ttRecJ was overexpressed in soluble form and purified. ttRecJ and cd-ttRecJ were stable up to 60 degrees C. Size exclusion chromatography indicated that ttRecJ exists in several oligomeric states, whereas cd-ttRecJ is monomeric in solution. Both proteins have 5'-->3' exonuclease activity, which was enhanced by increasing the temperature to 50 degrees C. Mg(2+), Mn(2+) or Co(2+) ions were required to activate both proteins, whereas Ca(2+) and Zn(2+) had no effects.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas de Escherichia coli , Exodesoxirribonucleasas/genética , Thermus thermophilus/genética , Secuencias de Aminoácidos/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Dicroismo Circular , Clonación Molecular , ADN Bacteriano/química , ADN Bacteriano/genética , ADN de Cadena Simple/genética , ADN de Cadena Simple/metabolismo , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Exodesoxirribonucleasas/aislamiento & purificación , Exodesoxirribonucleasas/metabolismo , Exonucleasas/metabolismo , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos/genética , Genoma Bacteriano , Cinética , Datos de Secuencia Molecular , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Espectrofotometría Ultravioleta , Temperatura
8.
Cancer Res ; 54(12): 3267-72, 1994 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-8205549

RESUMEN

Glial fibrillary acidic protein (GFAP)-positive astrocytoma cells were stably transfected with an expression vector carrying a murine complementary DNA for GFAP in the antisense orientation. Three stably transfected GFAP-negative transformants were identified by indirect immunofluorescence and expanded in vitro. The stably transfected and control cell clones were analyzed for morphological alterations, growth in monolayer and soft agar, adhesiveness, and in vitro invasive potential. In contrast to control astrocytoma cells which retained an astrocytic phenotype with polygonal or triangular cells extending multiple long and thin processes, the antisense GFAP-transfected cells demonstrated marked morphological alterations in the form of flat, epithelioid cells devoid of long, astrocytic glial processes. The antisense GFAP-transfected clones demonstrated a greater degree of cell crowding and piling at confluence than did controls. By tritiated thymidine analysis, the antisense GFAP-transfected cell clones demonstrated a 2-3-fold increase in incorporation of the radiolabel, suggesting an enhanced proliferative potential over controls. Antisense GFAP-transfected astrocytoma clones formed larger and more numerous colonies than did controls when tested for anchorage-independent growth in soft agar. Following a time-course adhesion assay, antisense GFAP-transfected astrocytoma clones were found to be less adherent to their substratum than controls. When assessed in an in vitro invasion assay system, antisense GFAP-transfected astrocytoma cells more readily penetrated Matrigel-coated filters than did controls. These data have shown that eliminating GFAP expression from astrocytoma cells has affected astrocytoma cell morphology and adhesion. The data also suggest that the growth and invasive potential of the antisense GFAP-transfected astrocytoma cells have been significantly enhanced by altering the expression of this glial-specific cytoskeletal protein in this experimental cell system.


Asunto(s)
Astrocitoma/genética , Astrocitoma/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , ADN sin Sentido/genética , ADN sin Sentido/farmacología , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/fisiología , Animales , Adhesión Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Clonales , Humanos , Ratones , Ratones Desnudos , Invasividad Neoplásica , Trasplante de Neoplasias , Células Madre Neoplásicas/patología , Transfección , Trasplante Heterólogo , Células Tumorales Cultivadas
9.
Cancer Res ; 47(2): 636-8, 1987 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-3098416

RESUMEN

The appearance of 5-[(L)-S-cysteinyl]dopa, a major product in pheomelanogenesis was examined in affected and nonaffected skins from 20 patients with clinical signs of dysplastic melanocytic nevi. Analysis by high performance liquid chromatography and electrochemical detection showed that 20 of the 35 lesions had a pathological formation of 5-[(L)-S-cysteinyl]dopa (0.04-28.86 ng/micrograms acid soluble protein). 5-[(L)-S-cysteinyl]dopa was not detected in any of the normal uninvolved skin samples analyzed.


Asunto(s)
Cisteinildopa/análisis , Dihidroxifenilalanina/análogos & derivados , Nevo Pigmentado/análisis , Biopsia , Cromatografía Líquida de Alta Presión , Humanos , Melanocitos/análisis , Lesiones Precancerosas/análisis , Piel/análisis
10.
Cancer Res ; 60(24): 6886-9, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11156386

RESUMEN

To identify the genes located downstream of the activated Ki-Ras signaling pathways in human colon cancer cells, a PCR-based cDNA subtraction library was constructed between HCT116 cells and HCT116-derived activated Ki-ras-disrupted cells (HKe3). One of the genes in HCT116 that was evidently up-regulated was epiregulin, a member of the epidermal growth factor family that is expressed in many kinds of human cancer cells. HKe3-stable transfectants expressing activated Ki-Ras regained over-expression of epiregulin. To further elucidate the biochemical structure and significance of epiregulin expression in tumorigenesis, HKe3-stable transfectants expressing epiregulin (e3-pSE cells) were established. Epiregulin existed as highly glycosylated membrane-bound forms, and TPA rapidly induced ectodomain shedding of epiregulin. Furthermore, the conditioned medium of e3-pSE cells showed more DNA synthesis for 32D cells expressing epidermal growth factor receptor (DER) cells than that of HKe3. Although anchorage-independent growth in soft agar was not observed for e3-pSE cells, tumorigenicity in nude mice was observed evidently, and their growth rate was correlated with each amount of exogenous epiregulin expression. These results suggested that activated Ki-Ras will be one of the factors contributing to the overexpression of epiregulin in human colon cancer cells, and that epiregulin will play a critical role in human tumorigenesis in vivo.


Asunto(s)
Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Genes ras/genética , Proteína Oncogénica p21(ras)/metabolismo , Transducción de Señal , Animales , Biotinilación , Northern Blotting , Medios de Cultivo Condicionados/metabolismo , ADN/metabolismo , ADN Complementario/metabolismo , Epirregulina , Biblioteca de Genes , Humanos , Ligandos , Ratones , Ratones Desnudos , Reacción en Cadena de la Polimerasa , Pruebas de Precipitina , Acetato de Tetradecanoilforbol/farmacología , Transfección , Células Tumorales Cultivadas , Regulación hacia Arriba
11.
Biochim Biophys Acta ; 965(2-3): 176-84, 1988 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-3365452

RESUMEN

Bradykinin-hydrolyzing enzyme was purified 200-fold from a soluble fraction of cornified cells from 2-day-old rat epidermis. The enzyme has an Mr of 80,000 as identified by SDS polyacrylamide gel electrophoresis and HPLC gel filtration. The isoelectric point of the enzyme is 5.05. The enzyme hydrolyzed Phe5-Ser6 of bradykinin and seven bradykinin-related peptides, and Tyr5-Ser6 of Tyr5-bradykinin. Production of bradykinin fragments, Arg-Pro-Pro-Gly-Phe and Ser-Pro-Phe-Arg, proceeded in a stoichiometric fashion. Km and Vmax values for bradykinin were 33 microM and 22.2 mumol/min per mg, respectively. The enzyme did not hydrolyze azocasein, denatured hemoglobin or synthetic substrates for other epidermal proteinases. The enzyme activity was enhanced by reducing agents and inhibited by sulfhydryl-blocking agents and divalent cations. Diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride had no effects. The enzyme has a pH optimum of 7.0-7.5 and is stable at 4 degrees C for 1 month, but loses activity completely at 60 degrees C for 10 min. The epidermal endopeptidase differs in several properties from endooligopeptidase A purified from brain which hydrolyzes Phe5-Ser6 of bradykinin.


Asunto(s)
Cisteína Endopeptidasas/aislamiento & purificación , Epidermis/enzimología , Secuencia de Aminoácidos , Animales , Animales Recién Nacidos/metabolismo , Bradiquinina/metabolismo , Cromatografía Líquida de Alta Presión , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa , Estabilidad de Medicamentos , Electroforesis en Gel de Poliacrilamida , Activación Enzimática/efectos de los fármacos , Concentración de Iones de Hidrógeno , Punto Isoeléctrico , Datos de Secuencia Molecular , Peso Molecular , Ratas , Ratas Endogámicas , Especificidad por Sustrato
12.
Biochim Biophys Acta ; 925(1): 48-56, 1987 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-3297171

RESUMEN

Cysteine proteinase inhibitor exists in two forms in terminally differentiated keratinocytes. One is readily soluble in 20 mM sodium phosphate buffer but the other is bound to the plasma membrane and is poorly soluble. The cysteine proteinase inhibitor (CPI) from the membrane was extracted from cornified epidermal layers of 2-day-old rats and its properties were compared with those of soluble CPI. This CPI (bound CPI) was solubilized in alkaline 8 M urea containing 2-mercaptoethanol from the residual tissue exhaustively treated with buffered 4 M urea. CPI was separated from keratin by ammonium sulfate precipitation and purified by means of papain affinity chromatography, ion exchange column chromatography and gel filtration. Bound CPI had an Mr value of about 16,000, a pI value of 3.8 and was unstable at above 80 degrees C, while soluble CPI was of Mr 13,000 and stable at above 80 degrees C. Both CPIs were stable at 4 degrees C in the range of 3.0-9.0. Bound CPI contained half cystine and the ratio of acidic-to-basic amino acids was 3.18. Bound CPI inhibited rat liver cathepsins B, H, and L but did not inhibit the activity of noncysteine proteinases. Papain activity was inhibited by bound CPI at three sites, noncompetitively, and the Ki value was calculated to be 0.11 nM.


Asunto(s)
Endopeptidasas/metabolismo , Epidermis/análisis , Inhibidores de Proteasas/aislamiento & purificación , Animales , Animales Recién Nacidos , Cisteína Endopeptidasas , Papaína/antagonistas & inhibidores , Ratas , Ratas Endogámicas
13.
Biochim Biophys Acta ; 579(2): 334-45, 1979 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-93971

RESUMEN

(1) Combination of techniques for extraction and purification of histidine rich protein established by several investigators were employed for comparison of histidine-rich protein in granular cells and cornified cells of newborn rats. (2) Histidine-rich protein extracted from the same cell fraction by two different techniques either in 1 M potassium phosphate buffer (Ugel) or in 4 M urea (Dale) showed identical elution profiles on CM 52 cellulose ion exchange chromatography and the same SDS polyacrylamide gel electrophoretic patterns. (3) Histidine-rich protein from granular cells contained polypeptides of larger molecular sizes than those in histidine-rich protein from cornfield cells, although amino acid composition of the two histidine-rich protein was non-distinguishable (histidine residue was more than 7%). (4) Antibodies raised in rabbits by injection of histidine rich protein from granular cells and that from cornfield cells immunologically cross-reacted. Furthermore, the antisera were found to be reactive over both keratohyalin granules and cornified cells, but not epidermal cells of the lower strata.


Asunto(s)
Histidina/análisis , Hialina/análisis , Queratinas/análisis , Proteínas/análisis , Piel/análisis , Animales , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Histidina/inmunología , Inmunoquímica , Proteínas/inmunología , Ratas , Solubilidad
14.
Biochim Biophys Acta ; 632(2): 214-26, 1980 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-6158344

RESUMEN

A protein solubilized in Tris-HCl/saline buffer from keratinized cells of newborn rat epidermis exhibited inhibitor activity to papain and ficin, but not to trypsin, cathepsin D and pepsin. This protein was purified from keratinized cells as well as nonkeratinized and germinative cells by means of IgG affinity chromatography. The inhibitors extracted from all cell layers were immunologically identical and had a molecular weight of approximately 12,500 +/- 500. Since amino acid analysis showed that the inhibitor contains about 35 residues of glycine per mol, [3H]glycine was used to investigate synthesis of the protein. The inhibitor from nonkeratinized and germinative cells was radioactively labeled by 2 h after injection and appeared in keratinized cells by 48 h after injection. Indirect immunofluorescence microscopy demonstrated in situ distribution of the protein in the entire epidermis, and the protein localized by the plasma membrane in granular cells and diffusely in keratinized cells was shown to be insoluble in Tris-HCl saline buffer. The results indicate that a thiol-proteinase inhibitor is synthesized in epidermal cells during keratinization and is retained as part of the cytoplasmic structure


Asunto(s)
Epidermis/metabolismo , Inhibidores de Proteasas/metabolismo , Aminoácidos/análisis , Animales , Animales Recién Nacidos , Ficaína/antagonistas & inhibidores , Queratinas/metabolismo , Peso Molecular , Papaína/antagonistas & inhibidores , Inhibidores de Proteasas/aislamiento & purificación , Ratas , Distribución Tisular
15.
Biochim Biophys Acta ; 439(1): 95-106, 1976 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-60135

RESUMEN

1. Proteins were extracted from cornified cells of newborn rats and human palm with 8 M urea containing 0.1 M beta-mercaptoethanol. Two fractions, rat FIIIa and human F5.5 were obtained by acid precipitation for further study. 2. Antibodies raised in rabbits by injection of rat FIIIa gave two precipitin lines by agarose diffusion against rat FIIIa, but only one line against human F5.5. One of the antigenic determinants of rat FIIIa was found to be a protein of approximately 66 000 daltons. The other seems to be formed with two polypeptides in the range of 60 000 and 66 000 daltons. The antigenic determinant of human F5.5 was a protein of approximately 64 000 daltons which immunologically cross-reacted only with the antiserum to a protein of 66 000 daltons in rat FIIIa. 3. The antisera also cross-reacted with proteins extracted from epidermis of guinea pig, hamster, hairless mouse, dog ear, dog snout and dog foot pad, but did not react with the epidermis of either rabbit immunized with rat FIIIa or non-treated normal rabbit. 4. Indirect immunofluorescence demonstrated a reaction of rabbit anti-rat FIIIa serum over cornified cells as well as over granular, spinous and basal cells of the epidermis of newborn rat and human.


Asunto(s)
Proteínas , Piel/análisis , Animales , Animales Recién Nacidos , Reacciones Cruzadas , Electroforesis en Gel de Poliacrilamida , Epítopos , Humanos , Inmunodifusión , Peso Molecular , Proteínas/inmunología , Ratas , Piel/inmunología , Piel/ultraestructura , Especificidad de la Especie
16.
Biochim Biophys Acta ; 707(1): 21-7, 1982 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-6753937

RESUMEN

Cysteine proteinase inhibitors isolated from rat and human epidermis were purified to homogeneity and had isoelectric points of pH 4.31 and pH 5.10, respectively, Both inhibitors caused noncompetitive inhibition to the same degree against papain (EC 3.4.22.2), but the activity of human inhibitor against rat liver cathepsins B (EC 3.4.22.1), H (EC 3.4.22.16), and L (EC 3.422.-) was more effective than that of rat inhibitor. Dependency on pH was observed with rat inhibitor for cathepsins B and H, and with human inhibitor for cathepsin L. The reaction of the inhibitors with papain and cathepsins H and L occurred immediately, while the inhibition reaction of cathepsin B increased progressively during a preincubation time up to 40 min. Incubation at pH 7.0 maximized the progressive inhibitory activity. These findings demonstrate that cysteine proteinase inhibitors from rat and human epidermis inhibited a variety of cysteine proteinases. However, the inhibitor and enzyme interaction depends upon the enzyme, inhibitor source, and experimental conditions such as pH and preincubation time.


Asunto(s)
Inhibidores de Proteasas/aislamiento & purificación , Proteínas/aislamiento & purificación , Piel/análisis , Animales , Animales Recién Nacidos , Cisteína Endopeptidasas , Inhibidores de Cisteína Proteinasa , Endopeptidasas , Humanos , Concentración de Iones de Hidrógeno , Cinética , Inhibidores de Proteasas/farmacología , Proteínas/farmacología , Ratas , Ratas Endogámicas , Especificidad de la Especie
17.
Biochim Biophys Acta ; 991(1): 19-24, 1989 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-2713418

RESUMEN

A tissue carboxypeptidase-A-like enzyme was purified to apparent homogeneity from terminally differentiated epidermal cells of 2-day-old rats by potato inhibitor affinity chromatography followed by FPLC Mono Q column chromatography. The enzyme has an Mr of 35,000 as determined by SDS-polyacrylamide gel electrophoresis and HPLC gel filtration. It has a pH optimum of 8.5 for hydrolysis of benzyloxycarbonyl-Phe-Leu (Km = 0.22 mM, kcat = 57.9 s-1). The enzyme does not hydrolyze substrates with Arg, Lys and Pro at the C-terminal and Pro at the penultimate position. Angiotensin I was effectively hydrolyzed (Km = 0.06 mM, kcat = 6.48 s-1) and produced both des-Leu10-angiotensin I and angiotensin II. The enzyme activity, relatively stable at 4 degrees C and pH 8.0-10.5, was inactivated at pH values higher than 12.0 and lower than 5.0 or at 65 degrees C for 10 min. Inhibitor profiles of the epidermal enzyme also differed slightly from those of tissue carboxypeptidase A of pancreatic or mast cell origin.


Asunto(s)
Carboxipeptidasas/aislamiento & purificación , Epidermis/enzimología , Angiotensina I/metabolismo , Animales , Carboxipeptidasas/antagonistas & inhibidores , Carboxipeptidasas/metabolismo , Carboxipeptidasas A , Cromatografía de Afinidad , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Encefalinas/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Mastocitos/enzimología , Ratas , Ratas Endogámicas , Especificidad por Sustrato
18.
Biochim Biophys Acta ; 624(1): 205-10, 1980 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-6157424

RESUMEN

Effects of CaCl2 on in vitro polymerization of keratin extracted from cornified cells of newborn rat were investigated by means of light-scattering and supramolecular structures. Elongation and parallel assembly of filaments occurred with addition of CaCl2 to dialyzed keratin solutions and was detected by an increase in light-scattering intensity. Nonfibrous aggregates which occurred in higher buffer concentrations and in lower pH were also recorded as intensity increased. MgCl2, ZnCl2, and GdCl3 demonstrated similar effects, but NaCl and KCl showed no effect.


Asunto(s)
Epidermis/ultraestructura , Queratinas/análisis , Animales , Animales Recién Nacidos , Tampones (Química) , Cloruro de Calcio/farmacología , Cationes Bivalentes/farmacología , Concentración de Iones de Hidrógeno , Queratinas/farmacología , Luz , Magnesio/farmacología , Metales de Tierras Raras/farmacología , Cloruro de Potasio/farmacología , Ratas , Dispersión de Radiación , Cloruro de Sodio/farmacología , Zinc/farmacología
19.
J Mol Biol ; 196(4): 961-2, 1987 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-3681987

RESUMEN

Tobacco necrosis virus is a spherical plant virus consisting of 180 copies of coat protein and a single-stranded RNA. The virus has been crystallized in cubic space group P4(2)32 with a = 338 A. The locations and the orientations of the two virus particles in the unit cell have been determined on the basis of the symmetries of both the particle and the crystal. The crystal diffracts X-rays to at least 2.5 A resolution and is quite stable to X-ray beams (1 A = 0.1 nm).


Asunto(s)
Virus de Plantas/ultraestructura , Difracción de Rayos X
20.
J Mol Biol ; 210(2): 383-98, 1989 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-2600971

RESUMEN

The structure of a low-potential ferredoxin isolated from Bacillus thermoproteolyticus has been refined by a restrained least-squares method. The final crystallographic R factor is 0.204 for 2906 reflections with F greater than 3 sigma F in the 6.0 to 2.3 A resolution range. The model contains 81 amino acid residues, one [4Fe-4S] cluster, and 59 water molecules. The root-mean-square deviation from ideal values for bond lengths is 0.018 A, and the mean coordinate error is estimated to be 0.25 A. The present ferredoxin is similar in the topology of the polypeptide backbone to the dicluster-type ferredoxins from Peptococcus aerogenes and Azotobacter vinelandii, but has considerable insertions and deletions of the peptide segments as well as different secondary structures. Although all but the C-terminal C zeta atoms of P. aerogenes ferredoxin superpose on the C alpha atoms of A. vinelandii ferredoxin, only 60% superpose on the C alpha atoms of B. thermoproteolyticus ferredoxin, with a root-mean-square distance of 0.82 A for each pair. The conformations of the peptide segments surrounding the [4Fe-4S] clusters in these three ferredoxins are all conserved. Moreover, the schemes for the NH...S hydrogen bonds in these ferredoxins are nearly identical. The site of the aromatic ring of Tyr27 in B. thermoproteolyticus ferredoxin is close spatially to that of Tyr28 in P. aerogenes ferredoxin with reference to the cluster, but these residues do not correspond in the spatial alignment of their polypeptide backbones. We infer that in monocluster-type ferredoxins, the side-chain at the 27th residue has a crucial effect on the stability of the cluster. Of the four cysteine residues that bind to the second Fe-S cluster in the dicluster-type ferredoxins, two are conserved in the monocluster-type ferredoxins from Desulfovibrio gigas. D. desulfuricans Norway, and Clostridium thermoaceticum. The tertiary structure of B. thermoproteolyticus ferredoxin suggests that in such monocluster-type ferredoxins these two cysteine residues, which in it correspond to Ala21 and Asp53, form a disulfide bridge.


Asunto(s)
Bacillus/enzimología , Ferredoxinas/ultraestructura , Secuencia de Aminoácidos , Cristalografía , Cisteína , Disulfuros , Enlace de Hidrógeno , Datos de Secuencia Molecular , Prolina , Conformación Proteica , Agua , Difracción de Rayos X
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