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1.
J Infect Dis ; 221(11): 1855-1863, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-31900482

RESUMEN

BACKGROUND: Noroviruses are a leading cause of acute gastroenteritis. Genogroup 2 type 4 (GII.4) has been the dominant norovirus genotype worldwide since its emergence in the mid-1990s. Individuals with a functional fucosyltransferase-2 gene, known as secretors, have increased susceptibility to GII.4 noroviruses. We hypothesized that this individual-level trait may drive GII.4 norovirus predominance at the human population level. METHODS: We conducted a systematic review for studies reporting norovirus outbreak or sporadic case genotypes and merged this with data on proportions of human secretor status in various countries from a separate systematic review. We used inverse variance-weighted linear regression to estimate magnitude of the population secretor-GII.4 proportion association. RESULTS: Two hundred nineteen genotype and 112 secretor studies with data from 38 countries were included in the analysis. Study-level GII.4 proportion among all noroviruses ranged from 0% to 100%. Country secretor proportion ranged from 43.8% to 93.9%. We observed a 0.69% (95% confidence interval, 0.19-1.18) increase in GII.4 proportion for each percentage increase in human secretor proportion, controlling for Human Development Index. CONCLUSIONS: Norovirus evolution and diversity may be driven by local population human host genetics. Our results may have vaccine development implications including whether specific antigenic formulations would be required for different populations.


Asunto(s)
Infecciones por Caliciviridae/transmisión , Infecciones por Caliciviridae/genética , Infecciones por Caliciviridae/virología , Brotes de Enfermedades/prevención & control , Femenino , Fucosiltransferasas , Genotipo , Salud Global , Humanos , Masculino , Norovirus/clasificación , Norovirus/genética , Filogenia , Galactósido 2-alfa-L-Fucosiltransferasa
2.
Int J Behav Nutr Phys Act ; 13: 59, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-27178056

RESUMEN

BACKGROUND: Most schools have not fully implemented wellness policies, and those that have rarely incorporate meaningful student participation. The aim of the Fuel Up to Play 60 (FUTP60) program is to help schools implement wellness policies by engaging students in activities to improve access to healthful, good tasting food and drinks, and increase the number and type of opportunities for students to be physically active. The aim of this paper is to present initial student-level results from an implementation of FUTP60 in 72 schools, grades 6-9. METHODS: The study used a non-controlled pretest/posttest with serial cross-sectional data. School process data and student-level data were collected in fall 2009 (pre-intervention) and spring 2010 (post-intervention). School wellness practices were captured during a baseline needs assessment survey. Validated self-administered questionnaires assessing dietary and physical activity (PA) behaviors were administered to students in grades 6-9 in the 72 pilot schools. Mixed-effects logistic regression controlling for clustering of schools and demographics was used to calculate odds ratios and confidence intervals to evaluate changes pre- and post- intervention. RESULTS: All 72 schools implemented FUTP60 during the 2009-2010 school year. Action strategies most frequently chosen by the schools included increasing breakfast participation and new activities before and after school. Positive and significant changes in students' behaviors (n = 32,482 at pretest and 29,839 at post-test) were noted for dairy, whole grains, fruit, and vegetable consumption and PA levels pre- and post-intervention (OR 1.05 to 1.27). Students aware of the program at post-test were significantly more likely to report healthier eating and PA behaviors than students unaware of the program (OR 1.1 to 1.34). CONCLUSIONS: FUTP60 pilot findings indicate that a low intensity program focused on wellness policy implementation is associated with small positive changes in student behaviors, especially when students were aware of the program. Although these initial results are promising, a more rigorous controlled study is warranted as a next step.


Asunto(s)
Dieta , Ejercicio Físico , Conducta Alimentaria , Conductas Relacionadas con la Salud , Promoción de la Salud/métodos , Servicios de Salud Escolar , Instituciones Académicas , Concienciación , Desayuno , Estudios Transversales , Ingestión de Alimentos , Ambiente , Femenino , Humanos , Proyectos Piloto , Políticas , Estudiantes
3.
bioRxiv ; 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38260588

RESUMEN

The immune system comprises multiple cell lineages and heterogeneous subsets found in blood and tissues throughout the body. While human immune responses differ between sites and over age, the underlying sources of variation remain unclear as most studies are limited to peripheral blood. Here, we took a systems approach to comprehensively profile RNA and surface protein expression of over 1.25 million immune cells isolated from blood, lymphoid organs, and mucosal tissues of 24 organ donors aged 20-75 years. We applied a multimodal classifier to annotate the major immune cell lineages (T cells, B cells, innate lymphoid cells, and myeloid cells) and their corresponding subsets across the body, leveraging probabilistic modeling to define bases for immune variations across donors, tissue, and age. We identified dominant tissue-specific effects on immune cell composition and function across lineages for lymphoid sites, intestines, and blood-rich tissues. Age-associated effects were intrinsic to both lineage and site as manifested by macrophages in mucosal sites, B cells in lymphoid organs, and T and NK cells in blood-rich sites. Our results reveal tissue-specific signatures of immune homeostasis throughout the body and across different ages. This information provides a basis for defining the transcriptional underpinnings of immune variation and potential associations with disease-associated immune pathologies across the human lifespan.

4.
Infect Immun ; 80(10): 3621-33, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22868499

RESUMEN

We developed means to deliver multiple heterologous antigens on dual plasmids with non-antibiotic-resistance markers in a single recombinant attenuated vaccine strain of Salmonella enterica serotype Typhimurium. The first component of this delivery system is a strain of S. Typhimurium carrying genomic deletions in alr, dadB, and asd, resulting in obligate requirements for diaminopimelic acid (DAP) and d-alanine for growth. The second component is the Asd(+)-DadB(+) plasmid pair carrying wild-type copies of asdA and dadB, respectively, to complement the mutations. To evaluate the protection efficacy of the dual-plasmid vaccine, S. Typhimurium strain χ9760 (a strain with multiple attenuating mutations: Δasd Δalr ΔdadB ΔrecF) was transformed with Asd(+) and DadB(+) plasmids specifying pneumococcal antigens PspA and PspC, respectively. Both plasmids were stable in χ9760 for 50 generations when grown in nonselective medium. This was significantly (P < 0.05) greater than the stability seen in its recF(+) counterpart χ9590 and could be attributed to reduced interplasmid recombination in χ9760. Oral immunization of BALB/c mice with 1 × 10(9) CFU of χ9760 (carrying Asd(+)-PspA and DadB(+)-PspC plasmids) elicited a dominant Th1-type serum IgG response against both antigens and protected mice against intraperitoneal challenge with 200 50% lethal doses (LD(50)s) of virulent Streptococcus pneumoniae strain WU2 or intravenous challenge with 100 LD(50)s of virulent S. pneumoniae strain L81905 or intranasal challenge with a lethal dose of S. pneumoniae A66.1 in a pneumonia model. Protection offered by χ9760 was superior to that offered by the mixture of two strains, χ9828 (Asd(+)-PspA) and χ11026 (DadB(+)-PspC). This novel dual-plasmid system marks a remarkable improvement in the development of live bacterial vaccines.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Plásmidos , Salmonelosis Animal/prevención & control , Vacunas contra la Salmonella/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Proteínas Bacterianas/genética , Femenino , Inmunoglobulina A/metabolismo , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C , Neumonía Neumocócica/prevención & control , Proteínas Recombinantes/inmunología , Salmonella typhimurium/inmunología , Vacunas Atenuadas , Vacunas Sintéticas
5.
Int J Microbiol ; 2021: 6631920, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33519936

RESUMEN

Fresh-produce consumers may be at risk of pathogen infection due to fecal contamination of the agricultural environment. Indicators of fecal contamination may be used as a proxy to evaluate the potential presence of human pathogens, such as norovirus and hepatitis A, on agricultural samples. The objective of this systematic review was to determine whether the presence of human norovirus or hepatitis A was associated with microbial indicators in agricultural samples including fresh produce, equipment surfaces, and hands. Four databases (Embase, PubMed, Web of Science, and Agricola) were systematically searched and fifteen articles met inclusion and exclusion criteria. After data extraction, individual indicator-pathogen relationships were assessed using Cohen's Kappa coefficient. The level of agreement between norovirus with adenovirus was 0.09 (n = 16, 95% CI -0.05, 0.23), indicating poor agreement using Landis and Koch's criterion. Similarly, the Kappa coefficient between norovirus with E. coli (κ = 0.04, n = 14, 95% CI -0.05, 0.49) or total coliforms (κ = 0.03, n = 4, 95% CI -0.01, 0.02) was also poor. The level of agreement between hepatitis A with adenovirus (κ = -0.03, n = 3, 95% CI -0.06, 0.01) or fecal coliforms (κ = 0, n = 1, 95% CI 0, 0) was also poor. There were moderate relationships between hepatitis A with E. coli (κ = 0.49, n = 3, 95% CI 0.28, 0.70) and total coliforms (κ = 0.47, n = 2, 95% CI 0.47, 0.47). Based on these limited results, common indicator organisms are not strong predictors of the presence of norovirus and hepatitis A virus in the agricultural environment.

6.
Front Cell Infect Microbiol ; 11: 676638, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34295834

RESUMEN

Introduction: Staphylococcus aureus strains, including methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA), are a main cause of nosocomial infection in the world. The majority of nosocomial S. aureus-infection are traced back to a source of contaminated surfaces including surgery tables. We assessed the efficacy of a mixture of levulinic acid (LA) and sodium dodecyl sulfate (SDS), hereafter called MoWa, to eradicate nosocomial pathogens from contaminated surfaces. Methods and Results: A dose response study demonstrated that MoWa killed 24 h planktonic cultures of S. aureus strains starting at a concentration of (LA) 8.2/(SDS) 0.3 mM while 24 h preformed biofilms were eradicated with 32/1.3 mM. A time course study further showed that attached MRSA bacteria were eradicated within 4 h of incubation with 65/2 mM MoWa. Staphylococci were killed as confirmed by bacterial counts, and fluorescence micrographs that were stained with the live/dead bacterial assay. We then simulated contamination of hospital surfaces by inoculating bacteria on a surface prone to contamination. Once dried, contaminated surfaces were sprayed with MoWa or mock-treated, and treated contaminated surfaces were swabbed and bacteria counted. While bacteria in the mock-treated samples grew at a density of ~104 cfu/cm2, those treated for ~1 min with MoWa (1.0/0.04 M) had been eradicated below limit of detection. A similar eradication efficacy was obtained when surfaces were contaminated with other nosocomial pathogens, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, or Staphylococcus epidermidis. Conclusions: MoWa kills planktonic and biofilms made by MRSA and MSSA strains and showed great efficacy to disinfect MRSA-, and MSSA-contaminated, surfaces and surfaces contaminated with other important nosocomial pathogens.


Asunto(s)
Infección Hospitalaria , Desinfectantes , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Desinfectantes/farmacología , Hospitales , Humanos , Staphylococcus aureus
7.
MSMR ; 28(6): 16-19, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34379381

RESUMEN

This report provides mid-season vaccine effectiveness (VE) estimates from the Armed Forces Health Surveillance Division (AFHSD), the DoD Global Respiratory Pathogen Surveillance (DoDGRS) program, and the Naval Health Research Center (NHRC) for the 2019-2020 influenza season. Using a test negative case-control study design, the AFHSD performed a VE analysis for active component service members while the DoDGRS program and NHRC collaborated to perform a VE analysis for DoD beneficiaries and U.S.-Mexico border civilians. Among active component service members, there was low to moderate protection against influenza B, moderate protection against A(H3N2), and non-statistically significant low protection against influenza A overall and A(H1N1). Among DoD beneficiaries and U.S.-Mexico border civilians, there was statistically significant moderate protection against influenza B, influenza A overall, A(H1N1), and A(H3N2).


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Personal Militar , Estudios de Casos y Controles , Humanos , Subtipo H3N2 del Virus de la Influenza A , Virus de la Influenza B , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Estaciones del Año , Vacunación
9.
J Mol Biol ; 353(2): 410-26, 2005 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-16169012

RESUMEN

S100A1 is an EF-hand-containing Ca(2+)-binding protein that undergoes a conformational change upon binding calcium as is necessary to interact with protein targets and initiate a biological response. To better understand how calcium influences the structure and function of S100A1, the three-dimensional structure of calcium-bound S100A1 was determined by multidimensional NMR spectroscopy and compared to the previously determined structure of apo. In total, 3354 nuclear Overhauser effect-derived distance constraints, 240 dihedral constraints, 160 hydrogen bond constraints, and 362 residual dipolar coupling restraints derived from a series of two-dimensional, three-dimensional, and four-dimensional NMR experiments were used in its structure determination (>21 constraints per residue). As with other dimeric S100 proteins, S100A1 is a symmetric homodimer with helices 1, 1', 4, and 4' associating into an X-type four-helix bundle at the dimer interface. Within each subunit there are four alpha-helices and a short antiparallel beta-sheet typical of two helix-loop-helix EF-hand calcium-binding domains. The addition of calcium did not change the interhelical angle of helices 1 and 2 in the pseudo EF-hand significantly; however, there was a large reorientation of helix 3 in the typical EF-hand. The large conformational change exposes a hydrophobic cleft, defined by residues in the hinge region, the C terminus, and regions of helix 3, which are important for the interaction between S100A1 and a peptide (TRTK-12) derived from the actin-capping protein CapZ.


Asunto(s)
Calcio/metabolismo , Estructura Terciaria de Proteína , Proteínas S100/química , Secuencia de Aminoácidos , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Péptidos/química , Péptidos/metabolismo , Unión Proteica , Estructura Secundaria de Proteína , Proteínas S100/genética , Proteínas S100/metabolismo , Alineación de Secuencia
10.
Eur J Pharmacol ; 438(3): 183-8, 2002 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-11909610

RESUMEN

We have investigated the effect of 2(4-((2-carboxymethyl)phenyl)ethylamino)-5'-N-ethylcarboxamidoadenosine (CGS 21680), a potent and selective agonist at adenosine A2A receptors, on pulmonary inflammation induced by allergen challenge in the ovalbumin-sensitised, Brown Norway rat. Aerosol administration of ovalbumin (5 mg x ml(-1) for 60 min; calculated dose 0.4 mg x kg(-1)) induced increases in bronchoalveolar lavage fluid leukocyte numbers, protein content and myeloperoxidase and eosinophil peroxidase activities measured 24 h post challenge. CGS 21680 (10 and 100 microg x kg(-1) given intratracheally (i.t.) 30 min before and 3 h after allergen challenge) inhibited dose-dependently all the parameters of inflammation. Qualitatively similar results were obtained with the glucocorticosteroid, budesonide (0.1, 1 and 10 mg x kg(-1) given 3 h prior to ovalbumin challenge). CGS 21680 given i.t. reduced blood pressure in anaesthetised rats at similar doses to those at which anti-inflammatory effects were manifested. Both the anti-inflammatory and hypotensive responses to CGS 21680 were blocked by pretreatment with the selective adenosine A2A receptor antagonist, 4-(2-(7-amino-2-(2-furyl)(1,2,4)triazolo(2,3-a(1,3,5)triazin-5-yl amino)ethyl)phenol (ZM 241385), 3 mg x kg(-1) p.o., 1 h prior to the agonist. Thus, CGS 21680 manifests broad-spectrum anti-inflammatory activity in a model of allergic asthma in the Brown Norway rat through activation of adenosine A2A receptors. The striking similarity to budesonide, a clinically used anti-inflammatory agent, suggests that adenosine A2A receptor agonists may be useful alternatives to glucocorticosteroids in the treatment of asthma.


Asunto(s)
Adenosina/análogos & derivados , Adenosina/farmacología , Asma/prevención & control , Fenetilaminas/farmacología , Agonistas del Receptor Purinérgico P1 , Alérgenos/inmunología , Animales , Antiinflamatorios/farmacología , Asma/inmunología , Presión Sanguínea/efectos de los fármacos , Budesonida/farmacología , Relación Dosis-Respuesta a Droga , Inflamación/patología , Inflamación/prevención & control , Pulmón/irrigación sanguínea , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Ovalbúmina/inmunología , Ratas , Ratas Endogámicas BN , Receptor de Adenosina A2A , Triazinas/farmacología , Triazoles/farmacología , Resistencia Vascular/efectos de los fármacos
11.
Int J Sports Phys Ther ; 7(2): 219-25, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22530195

RESUMEN

Individuals with midfoot injuries may present to physical therapists in a variety of clinical settings. The ability of the physical therapy practitioner to optimally manage the care of such an individual may be dependent on understanding the diagnostic imaging that is indicated or has been been completed. Among the potentially most debilitating midfoot injuries are Lisfranc fracture-dislocations. This case outlines the use of conventional radiology, standard computerized tomography (CT), and three-dimensional CT for differential diagnosis of Lisfranc and associated midfoot injury in a 26 year-old female recreational athlete. Her subsequent surgical and post-surgical management is briefly discussed.Physical therapists evaluating patients with suspected midfoot injuries should be cognizant of the tendency for Lisfranc injuries to escape initial detection, possibly precipitating misdiagnosis or delay to diagnosis. Nonweight-bearing radiography may be insensitive to demonstrating the anatomical disruption of significant midfoot injuries. Weight-bearing radiographic views along with selective use of MRI and CT aid in proper identification of injury to the tarsometatarsal joints and optimal management of patients with these injuries.

12.
Cancer Res ; 71(5): 1849-57, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21233335

RESUMEN

Activation of the translation initiation factor 4E (eIF4E) promotes malignant transformation and metastasis. Signaling through the AKT-mTOR pathway activates eIF4E by phosphorylating the inhibitory 4E binding proteins (4E-BP). This liberates eIF4E and allows binding to eIF4G. eIF4E can then be phosphorylated at serine 209 by the MAPK-interacting kinases (Mnk), which also interact with eIF4G. Although dispensable for normal development, Mnk function and eIF4E phosphorylation promote cellular proliferation and survival and are critical for malignant transformation. Accordingly, Mnk inhibition may serve as an attractive cancer therapy. We now report the identification of a potent, selective and orally bioavailable Mnk inhibitor that effectively blocks 4E phosphorylation both in vitro and in vivo. In cultured cancer cell lines, Mnk inhibitor treatment induces apoptosis and suppresses proliferation and soft agar colonization. Importantly, a single, orally administered dose of this Mnk inhibitor substantially suppresses eIF4E phosphorylation for at least 4 hours in human xenograft tumor tissue and mouse liver tissue. Moreover, oral dosing with the Mnk inhibitor significantly suppresses outgrowth of experimental B16 melanoma pulmonary metastases as well as growth of subcutaneous HCT116 colon carcinoma xenograft tumors, without affecting body weight. These findings offer the first description of a novel, orally bioavailable MNK inhibitor and the first preclinical proof-of-concept that MNK inhibition may provide a tractable cancer therapeutic approach.


Asunto(s)
Antineoplásicos/farmacología , Benzofuranos/farmacología , Factor 4E Eucariótico de Iniciación/metabolismo , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Neoplasias Pulmonares/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Secuencia de Bases , Western Blotting , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Concentración 50 Inhibidora , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Metástasis de la Neoplasia/tratamiento farmacológico , Fosforilación , Reacción en Cadena de la Polimerasa , Proteínas Serina-Treonina Quinasas/genética , Ensayos Antitumor por Modelo de Xenoinjerto
13.
J Sch Health ; 80(11): 527-35; quiz 570-2, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21039551

RESUMEN

BACKGROUND: School wellness policies are a key component to the prevention of adolescent obesity. This national research study sought to understand the wellness environment in school districts across the country and to identify challenges districts face and needs they have in order to effectively implement, monitor, and evaluate school wellness policies. The study determined (1) perceptions, barriers, and opportunities regarding the development, implementation, and monitoring/evaluation of school wellness policies among school board members, state school boards association leaders, state public health nutrition directors, and school wellness advocates; (2) the readiness and capacity of survey groups to address nutrition and physical activity policies; (3) the extent to which survey groups collaborate; and (4) the acceptability of wellness tools. METHODS: In 2006, over 2900 individuals participated in online surveys, focus groups, and key informant interviews. School board members represented 1296 school districts across the nation. RESULTS: School board members expressed the highest level of confidence among all survey groups that their district has the capacity to develop, implement, and monitor/ evaluate the wellness policy. The disparities among groups are most notable with regard to perceptions of district capacity to monitor/evaluate the policy. School board members are interested in school wellness policy tools and trainings. CONCLUSIONS: There is an opportunity for state school boards associations, state public health nutrition directors, and school wellness advocates to build their own capacity to provide training and resources to districts on wellness issues, particularly physical education/activity, school-based wellness initiatives, and strategies for implementing and monitoring/evaluating wellness policies.


Asunto(s)
Protección a la Infancia/estadística & datos numéricos , Promoción de la Salud/organización & administración , Obesidad/prevención & control , Educación y Entrenamiento Físico/estadística & datos numéricos , Servicios de Salud Escolar/estadística & datos numéricos , Instituciones Académicas/organización & administración , Adolescente , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Ejercicio Físico , Femenino , Política de Salud , Humanos , Masculino , Obesidad/epidemiología , Servicios de Salud Escolar/organización & administración , Estados Unidos/epidemiología
14.
Arch Biochem Biophys ; 403(2): 160-70, 2002 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-12139965

RESUMEN

The broadly reactive cysteine protease dipeptidyl peptidase I (DPPI, cathepsin C) is thought to activate all progranzymes (zymogens of lymphocyte serine proteases) to form mature granzymes. We synthesized dipeptide 7-amino-4-methylcoumarin (AMC) substrates containing progranzyme activation sequences and showed that they were efficiently hydrolyzed by DPPI. However, DPPI will not hydrolyze Ile-Ile-AMC, the N-terminal dipeptide sequence found in mature granzymes. Introduction of the nonphysiological homophenylalanine (Hph) residue at P1 resulted in the best substrate Ala-Hph-AMC for DPPI (k(cat)/K(m)=9,000,000M(-1)s(-1)). The charged N-terminal amino group of the substrate was essential and replacement of the NH(2) group with OH or NH(CH(3)) in Gly-Phe-AMC reduced the k(cat)/K(m) value by two to three orders of magnitude. A hydrazide azaglycine analog, NH(2)NHCO-Phe-AMC, was not hydrolyzed at pH 5.5, but underwent slow hydrolysis at lower pHs where the amino group is partially protonated. DPPI also failed to hydrolyze NH(2)COCH(2)-Phe-AMC, where the NH(2) group is unprotonated. The results reported in this paper should be useful in the design of better DPPI inhibitors to block granzyme maturation and granzyme-dependent apoptosis.


Asunto(s)
Catepsina C/metabolismo , Dominio Catalítico , Catepsina C/química , Cumarinas/química , Concentración de Iones de Hidrógeno , Cinética , Especificidad por Sustrato
15.
Biochemistry ; 41(42): 12670-80, 2002 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-12379109

RESUMEN

Mts1 is a member of the S100 family of Ca2+-binding proteins and is implicated in promoting tumor progression and metastasis. To better understand the structure-function relationships of this protein and to begin characterizing its Ca2+-dependent interaction with protein binding targets, the three-dimensional structure of mts1 was determined in the apo state by NMR spectroscopy. As with other S100 protein family members, mts1 is a symmetric homodimer held together by noncovalent interactions between two helices from each subunit (helices 1, 4, 1', and 4') to form an X-type four-helix bundle. Each subunit of mts1 has two EF-hand Ca2+-binding domains: a pseudo-EF-hand (or S100-hand) and a typical EF-hand that are brought into proximity by a small two-stranded antiparallel beta-sheet. The S100-hand is formed by helices 1 and 2, and is similar in conformation to other members of the S100 family. In the typical EF-hand, the position of helix 3 is similar to that of another member of the S100 protein family, calcyclin (S100A6), and less like that of other S100 family members for which three-dimensional structures are available in the calcium-free state (e.g., S100B and S100A1). The differences in the position of helix 3 in the apo state of these four S100 proteins are likely due to variations in the amino acid sequence in the C-terminus of helix 4 and in loop 2 (the hinge region) and could potentially be used to subclassify the S100 protein family.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular , Proteínas S100/química , Secuencia de Aminoácidos , Apoproteínas/química , Proteínas de Unión al Calcio/química , Dimerización , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular/métodos , Conformación Proteica , Estructura Secundaria de Proteína , Proteína de Unión al Calcio S100A4 , Homología de Secuencia de Aminoácido , Soluciones , Homología Estructural de Proteína
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