The Xp10 bacteriophage protein P7 inhibits transcription by the major and major variant forms of the host RNA polymerase via a common mechanism

The σ factor is a functionally obligatory subunit of the bacterial transcription machinery, the RNA polymerase. Bacteriophage-encoded small proteins that either modulate or inhibit the bacterial RNAP to allow the temporal regulation of bacteriophage gene expression often target the activity of the major bacterial σ factor, σ70. Previously, we showed that during Xanthomonas oryzae phage Xp10 infection, the phage protein P7 inhibits the host RNAP by preventing the productive engagement with the promoter and simultaneously displaces the σ70 factor from the RNAP. In this study, we demonstrate that P7 also inhibits the productive engagement of the bacterial RNAP containing the major variant bacterial σ factor, σ54, with its cognate promoter. The results suggest for the first time that the major variant form of the host RNAP can also be targeted by bacteriophage-encoded transcription regulatory proteins. Since the major and major variant σ factor interacting surfaces in the RNAP substantially overlap, but different regions of σ70 and σ54 are used for binding to the RNAP, our results further underscore the importance of the σ–RNAP interface in bacterial RNAP function and regulation and potentially for intervention by antibacterials

America\u27s Struggle To Develop A Consistent Legal Approach To Controversial Human Embryonic Stem Cell Research And Therapeutic Cloning: Are The Politics Getting In the Way Of Hope?

Part I of this note evaluates human embryonic stem cell research, including an explanation of the potential benefits of this procedure and the ethical debates surrounding this type of research. Part I also identifies the legal approach to human embryonic stem cell research currently used in the U.S. Next, Part I addresses therapeutic cloning. First, therapeutic cloning is explained and then distinguished from reproductive cloning. Second, Part I discusses the ethical concerns that arise from therapeutic cloning. Third, Part I outlines the current U.S. legal approach to therapeutic cloning. Part II of this note explains the British approach to both of these controversial research procedures. Part III describes the state of unregulated, private genetic research in the U.S. Finally, Part IV proposes that the U.S. adopt a legal scheme similar to that in Britain regarding human embryonic stem cell research and therapeutic cloning

‘Younger People Have Like More of an Imagination, No Offence’: Participant Perspectives on Public Engagement

© 2012, Copyright Taylor & Francis Group, LLC. A wide range of work has reported on the outcomes of public engagement activities and the views expressed by public participants towards specific areas of science and technology. Such work has rarely gone on to explore with public participants their attitudes to the engagement experienced itself, often focusing instead on more practical or quantifiable aspects. This article draws on public participants’ reactions to 11 ‘engagement’ events, occurring across the UK in 2007–2008. Reporting on 33 semi-structured interviews, we focus on their views of participation and engagement in terms of motivations, expectations and expertise. The results suggest that participants have considerable expectations in terms of information and interaction, operate with critical but respectful notions of other ‘publics’ and expertise, and may develop habitual tendencies regarding engagement

Use of Carbon Fiber Composite Molecular Sieves for Air Separation

A novel adsorbent material, 'carbon fiber composite molecular sieve' (CFCMS), has been developed by the Oak Ridge National Laboratory. Its features include high surface area, large pore volume, and a rigid, permeable carbon structure that exhibits significant electrical conductivity. The unique combination of high adsorptive capacity, permeability, good mechanical properties, and electrical conductivity represents an enabling technology for the development of novel gas separation and purification systems. In this context, it is proposed that a fast-cycle air separation process that exploits a kinetic separation of oxygen and nitrogen should be possible using a CFCMS material coupled with electrical swing adsorption (ESA). The adsorption of O{sub 2}, N{sub 2}, and CO{sub 2} on activated carbon fibers was investigated using static and dynamic techniques. Molecular sieving effects in the activated carbon fiber were highlighted by the adsorption of CO{sub 2}, a more sensitive probe molecule for the presence of microporosity in adsorbents. The kinetic studies revealed that O2 was more rapidly adsorbed on the carbon fiber than N{sub 2}, and with higher uptake under equilibrium conditions, providing the fiber contained a high proportion of very narrow micropores. The work indicated that CFCMS is capable of separating O{sub 2} and N{sub 2} from air on the basis of the different diffusion rates of the two molecules in the micropore network of the activated carbon fibers comprising the composite material. In response to recent enquires from several potential users of CFCMS materials, attention has been given to the development of a viable continuous process for the commercial production of CFCMS material. As part of this effort, work was implemented on characterizing the performance of lignin-based activated carbon fiber, a potentially lower cost fiber than the pitch-based fibers used for CFCMS production to date. Similarly, to address engineering issues, measurements were made to characterize the pressure drop of CFCMS as a function of carbon fiber dimensions and monolith density