RESUMEN
There is a lack of shuttle vectors to be needed for investigations into the genetics of Porphyromonas gingivalis and related species. To better understand the prevalence of candidates for such tools, we have examined multiple strains of black-pigmented anaerobes (clinical and laboratory isolates) for plasmids. As no plasmids were found in P. gingivalis strains, we have used the pYH420 plasmid, derived from P. asaccharolytica, as backbone to construct a shuttle vector in combination with pUC19 from Escherichia coli. Nucleotide sequence determination of the pYH420 plasmid revealed that it contained a gene with similarity to rep from plasmid pTS1 (isolated from Treponema denticola) as well as a homolog of mobA, a member of a gene family found on mobilizable genetic elements found in the genus Bacteroides. We constructed the pG106 and pG108 shuttle vectors using parts of the pUC19 and pYH420 vectors. This resulted in a vector with a multiple cloning site (MCS) in the lacZ gene enabling us to perform blue-white colony selection. The pG106 and pG108 shuttle vectors are electro-transformable into E. coli, P. gingivalis and B. thetaiotaomicron, where they are stable. We demonstrated that these vectors were suitable in these species for applications of molecular cloning including complementation and gene expression studies. Using the pG108 vector, we complement the hcpR mutant strain of P. gingivalis and rescued its NO2- -sensitive phenotype. We also performed a gene expression study using the P-glow BS2 fluorescent reporter gene and the ahpC promoter in B. thetaiotaomicron.
Asunto(s)
Bacteroides , Porphyromonas , Bacteroides/genética , Clonación Molecular , Escherichia coli/genética , Vectores Genéticos/genética , Plásmidos/genéticaRESUMEN
Policies and processes dealing with institutional conflict of interest (iCOI) lag well behind those dealing with individual COI. To remediate this, academic institutions must develop strategies for addressing some of the unique challenges in iCOI, including: clarifying the definition of iCOI that addresses the range of individuals potentially involved; implementing a well-designed electronic database for reporting and managing iCOI across multiple leadership constituencies; and providing ongoing education to appropriate institutional officials that communicates the importance of managing iCOI.
Asunto(s)
Conflicto de Intereses , Universidades , Humanos , Liderazgo , OrganizacionesRESUMEN
Examination of a limited number of publisher's Instructions for Authors, guidelines from two scientific societies, and the widely accepted policy document of the International Committee of Medical Journal Editors (ICMJE) provided useful information on authorship practices. Three of five journals examined (Nature, Science, and the Proceedings of the National Academy of Sciences) publish papers across a variety of disciplines. One is broadly focused on topics in medical research (New England Journal of Medicine) and one publishes research reports in a single discipline (Journal of Bacteriology). Similar elements of publication policy and accepted practices were found across the policies of these journals articulated in their Instructions for Authors. A number of these same elements were found in the professional society guidelines of the Society for Neuroscience and the American Chemical Society, as well as the ICMJE Uniform Requirements for Manuscripts Submitted to Biomedical Journals. Taken together, these sources provide the basis for articulating best practices in authorship in scientific research. Emerging from this material is a definition of authorship, as well as policy statements on duplicative publication, conflict of interest disclosure, electronic access, data sharing, digital image integrity, and research requiring subjects' protection, including prior registration of clinical trials. These common elements provide a foundation for teaching about scientific authorship and publication practices across biomedical and life sciences disciplines.
Asunto(s)
Autoria/normas , Disciplinas de las Ciencias Biológicas/normas , Investigación Biomédica/normas , Políticas Editoriales , Ética en Investigación/educación , Publicaciones Periódicas como Asunto/normas , Disciplinas de las Ciencias Biológicas/ética , Investigación Biomédica/ética , Derechos de Autor , Guías como Asunto , Humanos , Publicaciones Periódicas como Asunto/ética , Mala Conducta CientíficaRESUMEN
Scientific societies have a significant opportunity to contribute to the promotion of responsible conduct of research (RCR) and to RCR education. The degree to which societies engage such opportunity spans a broad range. There are three principal ways RCR may be promoted by scientific societies. The first is through codes of conduct encouraging their membership to practice ethical research according to the tenets of these codes. The second is through specialized policies (e.g., publication practices) developed by scientific societies that help define normative behavior. Finally, societies have a role to play in creating materials and resources aimed at educating scientists and trainees in matters pertaining to proper research conduct. This article illustrates examples of each of these activities embraced by different scientific societies. The American Society for Microbiology is used as a specific example of a society that has been proactive in each of these three areas. Scientific societies need to recognize the impact they can have on promoting RCR and to expand their efforts in these three and other relevant areas. The examples provided demonstrate the components of a model for all scientific societies to follow in promoting RCR.
Asunto(s)
Investigación Biomédica/educación , Investigación Biomédica/ética , Códigos de Ética , Ética en Investigación/educación , Investigadores/educación , Responsabilidad Social , Sociedades Científicas/normas , Humanos , Política Organizacional , Rol Profesional , Investigadores/ética , Sociedades Científicas/ética , Estados UnidosRESUMEN
The genome of Streptococcus sanguinis is a circular DNA molecule consisting of 2,388,435 bp and is 177 to 590 kb larger than the other 21 streptococcal genomes that have been sequenced. The G+C content of the S. sanguinis genome is 43.4%, which is considerably higher than the G+C contents of other streptococci. The genome encodes 2,274 predicted proteins, 61 tRNAs, and four rRNA operons. A 70-kb region encoding pathways for vitamin B(12) biosynthesis and degradation of ethanolamine and propanediol was apparently acquired by horizontal gene transfer. The gene complement suggests new hypotheses for the pathogenesis and virulence of S. sanguinis and differs from the gene complements of other pathogenic and nonpathogenic streptococci. In particular, S. sanguinis possesses a remarkable abundance of putative surface proteins, which may permit it to be a primary colonizer of the oral cavity and agent of streptococcal endocarditis and infection in neutropenic patients.
Asunto(s)
Genoma Bacteriano , Streptococcus/genética , Proteínas Bacterianas/análisis , Proteínas Bacterianas/metabolismo , Composición de Base , Placa Dental/microbiología , Transferencia de Gen Horizontal , Humanos , Datos de Secuencia Molecular , Infecciones Oportunistas/microbiología , ARN Bacteriano/metabolismo , ARN de Transferencia/metabolismo , Infecciones Estreptocócicas/microbiología , Streptococcus/patogenicidad , Operón de ARNrRESUMEN
We have studied postdoctoral trainees funded by NIH F32 fellowship awards in order to test the effectiveness of responsible conduct of research (RCR) education in the areas of authorship and publication practices. We used a 3-wave telephone and on-line survey design, conducted over a period of two years, in order to test for individual change before and after completing RCR education. Overall the responses of the subjects suggested a clear awareness of standards and practices in publication. However, our results failed to suggest that RCR education in this group significantly increased the level of ethically appropriate behavioral responses measured in the study. Similarly we saw no significant effect on increasing awareness of or attention to ethical guidelines about authorship and publication practices. Our interpretation of these null findings was influenced by the significant publication experience of our cohort of subjects. We forward possible explanations for these null findings in this context. Most importantly, we do not suggest that our results argue against continued instruction in RCR education. Instead, we believe our data reinforce the importance of careful articulation of course goals and objectives with attention to the background and experience of the student audience when developing RCR curricula.
Asunto(s)
Autoria , Ética en Investigación/educación , Becas , Adhesión a Directriz , Capacitación en Servicio , Edición/ética , Concienciación , Curriculum , Humanos , National Institutes of Health (U.S.) , Evaluación de Programas y Proyectos de Salud , Edición/normas , Estados UnidosRESUMEN
We have conducted a longitudinal survey of NIH-funded F32 postdoctoral fellows to determine if mandated instruction in the responsible conduct of research (RCR) has measurable effects on awareness of, attentiveness to, and behavioral judgments about research ethics and authorship and publication. Of 418 F32 fellows participating in the study, 50% were aware of and had referred to guidelines on authorship and publication practices while 50% were either unaware of or had not referred to guidelines. Groups were similar with regard to total number of peer-reviewed publications and total number of first author publications, years of research experience, years since completing their doctoral degree, and receipt of RCR training. The equal distribution of guideline awareness and use, and group similarities with regard to career development and achievement provided us with an opportunity to consider whether awareness of and use of guidelines is associated with broader judgments about author roles and responsibilities. The findings suggest that awareness and utilization of guidelines are, at best, only modestly associated with more ethically appropriate judgments and attitudes about author roles and responsibilities among novice F32's.
Asunto(s)
Autoria , Investigación Biomédica/ética , Investigación Biomédica/normas , Educación , Ética en Investigación/educación , Adhesión a Directriz , Conocimientos, Actitudes y Práctica en Salud , Edición/ética , Investigadores/ética , Recolección de Datos , Ética Profesional/educación , Estudios de Evaluación como Asunto , National Institutes of Health (U.S.) , Revisión de la Investigación por Pares , Edición/estadística & datos numéricos , Apoyo a la Investigación como Asunto , Estados UnidosRESUMEN
The FimA protein of Streptococcus parasanguis is a virulence factor in the rat model of endocarditis, and immunization with FimA protects rats against homologous bacterial challenge. Because FimA-like proteins are widespread among the oral streptococci, the leading cause of native valve endocarditis, we evaluated the ability of this vaccinogen to protect rats when challenged by other streptococcal species. Here we report that FimA vaccination produced antibodies that cross-reacted with and protected against challenge by the oral streptococci S. mitis, S. mutans, and S. salivarius. FimA thus has promise as a vaccinogen to control infective endocarditis caused by oral streptococci.
Asunto(s)
Proteínas Bacterianas/inmunología , Endocarditis Bacteriana/prevención & control , Proteínas Fimbrias , Vacunas Estreptocócicas/inmunología , Streptococcus/inmunología , Vacunas Sintéticas/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Reacciones Cruzadas , Modelos Animales de Enfermedad , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes de Fusión/inmunología , Streptococcus mutans/inmunología , VacunaciónRESUMEN
pBF4 is a 41 kb conjugative R-plasmid that confers MLS (macrolide-lincosamide-streptogramin B) resistance in Bacteroides spp. To identify pBF4 genes governing conjugation, recombinational mutagenesis using a suicide vector carrying fragments of the pBF4 plasmid was employed. One of the six independent insertion mutants of pBF4 isolated using this method was found to be conjugation-deficient. Nucleotide sequence analysis around the insertion site on this plasmid revealed a 2.8 kb ORF that encoded a putative 110 kDa protein. A corresponding protein was observed when a 12 kb DNA fragment containing this ORF was used to program an in vitro transcription-translation system. Both the ORF and the predicted protein were novel when compared to available database sequences. This gene was designated bctA (Bacteroides conjugal transfer). Polyclonal rabbit antibodies that recognized a sub-sequence polypeptide of BctA reacted with a 55 kDa protein in Western blot analysis using a total protein extract from Bacteroides fragilis containing pBF4. The protein was not present in a B. fragilis strain containing the conjugation-deficient insertion mutant of pBF4. The 55 kDa protein was associated with the membrane fraction of B. fragilis. Although the cellular and biochemical basis of bctA-promoted conjugation remains unknown, this work demonstrates the existence of a heretofore unrecognized gene in bacterial conjugation, and the mutagenesis system used provides the means to isolate and characterize other genes involved in conjugal transfer in Bacteroides spp.