Public health response to a measles outbreak in a large correctional facility, Queensland, 2013

This report documents the prompt, co-ordinated and effective public health response to a measles outbreak in Queensland in 2013. There were 17 cases in a large, high-security, regional correctional facility, a setting with unique challenges. Recommendations are provided to reduce the likelihood and magnitude of measles outbreaks in correctional facilities

The timing of TCRα expression critically influences T cell development and selection

Sequential rearrangement of the T cell receptor for antigen (TCR) β and α chains is a hallmark of thymocyte development. This temporal control is lost in TCR transgenics because the α chain is expressed prematurely at the CD4−CD8− double negative (DN) stage. To test the importance of this, we expressed the HYα chain at the physiological CD4+CD8+ double positive (DP) stage. The reduced DP and increased DN cellularity typically seen in TCR transgenics was not observed when the α chain was expressed at the appropriate stage. Surprisingly, antigen-driven selection events were also altered. In male mice, thymocyte deletion now occurred at the single positive or medullary stage. In addition, no expansion of CD8αα intestinal intraepithelial lymphocytes (IELs) was observed, despite the fact that HY transgenics have been used to model IEL development. Collectively, these data establish the importance of proper timing of TCR expression in thymic development and selection and emphasize the need to use models that most accurately reflect the physiologic process

Structure and function of the bacterial heterodimeric ABC transporter CydDC: stimulation of ATPase activity by thiol and heme compounds.

In Escherichia coli, the biogenesis of both cytochrome bd-type quinol oxidases and periplasmic cytochromes requires the ATP-binding cassette-type cysteine/GSH transporter, CydDC. Recombinant CydDC was purified as a heterodimer and found to be an active ATPase both in soluble form with detergent and when reconstituted into a lipid environment. Two-dimensional crystals of CydDC were analyzed by electron cryomicroscopy, and the protein was shown to be made up of two non-identical domains corresponding to the putative CydD and CydC subunits, with dimensions characteristic of other ATP-binding cassette transporters. CydDC binds heme b. Detergent-solubilized CydDC appears to adopt at least two structural states, each associated with a characteristic level of bound heme. The purified protein in detergent showed a weak basal ATPase activity (approximately 100 nmol Pi/min/mg) that was stimulated ∼3-fold by various thiol compounds, suggesting that CydDC could act as a thiol transporter. The presence of heme (either intrinsic or added in the form of hemin) led to a further enhancement of thiol-stimulated ATPase activity, although a large excess of heme inhibited activity. Similar responses of the ATPase activity were observed with CydDC reconstituted into E. coli lipids. These results suggest that heme may have a regulatory role in CydDC-mediated transmembrane thiol transport

The Vehicle, 1966, Vol. 8

Vol. 8 Table of Contents CommentaryBill Moser & Avis Eaglestonpage 3 The Vengeance of the DeadStephen W. Gibbspage 5 Ode To A MeadowKathleen McCormackpage 12 Row OnDavid Helmpage 13 Sonnet 63R.L. Hudsonpage 14 UntitledKathleen McCormackpage 14 The Pure GoldDavid Helmpage 15 CommunionDavid Helmpage 15 PreludeMichael Baldwinpage 15 The AlbatrossKaren Cooleypage 16 The Albatross (photo)DeWittpage 17 Ruff and the VaseDavid Helmpage 18 LaBelleKathleen McCormackpage 19 Not Quite SoR.L. Hudsonpage 20 Feeling (no number)David Reifpage 21 Song at DuskDavid Helmpage 21 Arcadia RuminationsR.L. Hudsonpage 22 The BarWayne Johnsonpage 25 HelloWilliam Framepage 26 The ProcessJerry DeWittpage 27 The KillingAdrian Beardpage 30 The Amusement Park GameStephen W. Gibbspage 38 DamnMel Tylerpage 40 PainWilliam Framepage 40 UntitledSusan Champlinpage 41 Portrait of A Scholar As A Young ManStephen W. Gibbspage 42 The TimesW.D.Mpage 46 ParadoxW.D.M.page 46 MankindDavid Helmpage 47https://thekeep.eiu.edu/vehicle/1014/thumbnail.jp

The Vehicle, 1966, Vol. 8

Vol. 8 Table of Contents CommentaryBill Moser & Avis Eaglestonpage 3 The Vengeance of the DeadStephen W. Gibbspage 5 Ode To A MeadowKathleen McCormackpage 12 Row OnDavid Helmpage 13 Sonnet 63R.L. Hudsonpage 14 UntitledKathleen McCormackpage 14 The Pure GoldDavid Helmpage 15 CommunionDavid Helmpage 15 PreludeMichael Baldwinpage 15 The AlbatrossKaren Cooleypage 16 The Albatross (photo)DeWittpage 17 Ruff and the VaseDavid Helmpage 18 LaBelleKathleen McCormackpage 19 Not Quite SoR.L. Hudsonpage 20 Feeling (no number)David Reifpage 21 Song at DuskDavid Helmpage 21 Arcadia RuminationsR.L. Hudsonpage 22 The BarWayne Johnsonpage 25 HelloWilliam Framepage 26 The ProcessJerry DeWittpage 27 The KillingAdrian Beardpage 30 The Amusement Park GameStephen W. Gibbspage 38 DamnMel Tylerpage 40 PainWilliam Framepage 40 UntitledSusan Champlinpage 41 Portrait of A Scholar As A Young ManStephen W. Gibbspage 42 The TimesW.D.Mpage 46 ParadoxW.D.M.page 46 MankindDavid Helmpage 47https://thekeep.eiu.edu/vehicle/1014/thumbnail.jp

The allantoin transport protein, PucI, from Bacillus subtilis: evolutionary relationships, amplified expression, activity and specificity

This work reports the evolutionary relationships, amplified expression, functional characterisation and purification of the putative allantoin transport protein, PucI, from Bacillus subtilis. Sequence alignments and phylogenetic analysis confirmed close evolutionary relationships between PucI and membrane proteins of the nucleobase-cation-symport-1 family of secondary active transporters. These include the sodium-coupled hydantoin transport protein, Mhp1, from Microbacterium liquefaciens and related proteins from bacteria, fungi and plants. Membrane topology predictions for PucI were consistent with twelve putative transmembrane-spanning α-helices with both N- and C-terminal ends at the cytoplasmic side of the membrane. The pucI gene was cloned into the IPTG-inducible plasmid pTTQ18 upstream from an in-frame hexahistidine tag and conditions are described for optimal amplified expression of the PucI(His6) protein in Escherichia coli to a level of about 5% in inner membranes. Initial rates of inducible PucI-mediated uptake of 14C-allantoin into energised Escherichia coli whole cells conformed to Michaelis-Menten kinetics with an apparent affinity (Kmapp) of 24 ± 3M, therefore confirming that PucI is a medium affinity transporter of allantoin. Dependence of allantoin transport on sodium was not apparent. Competitive uptake experiments showed that PucI recognises some additional hydantoin compounds, including hydantoin itself, and to a lesser extent a range of nucleobases and nucleosides. PucI(His6) was solubilised from inner membranes using n-dodecyl-β-D-maltoside and purified. The isolated protein comprised a substantial proportion of α-helix secondary structure, consistent with the predictions, and a three-dimensional model was therefore constructed on a template of the Mhp1 structure, which aided localisation of the potential ligand binding site in PucI

A search for AGN in the most extreme UV-selected starbursts using the European VLBI Network

We have used the European VLBI Network (EVN) to observe a sample of Lyman Break Analogs (LBAs), nearby (z < 0.3) galaxies with properties similar to the more distant Lyman Break Galaxies (LBGs). The study of LBGs may help define the feed-back relationship between black holes (BHs) and their host galaxies. Previous VLA observations have shown that the kpc-scale radio emission from LBAs is dominated by starbursts. The main targets of this VLBI experiment were selected because they possessed emission-line properties between starbursts and Type 2 (obscured) AGN. Eight targets (three star-forming LBAs, four composite LBAs, and one Type 1 AGN) were observed at 5 GHz, four of which were also observed at 1.7 GHz. One star-forming LBA and one composite LBA were detected above 5 \sigma at 1.7 GHz (only), while the AGN was detected at 5 GHz. In both LBAs, the radio luminosity (LR) exceeds that expected from supernovae (remnants) based on a comparison with Arp220, Arp229A and Mrk273, by factors of 2 - 8. The composite LBA exhibits a compact core emitting around 10% of the VLA flux density. The high Tb of 3.5E7 K and excess core L_R with respect to the L_R/L_X relation of radio-quiet AGN indicate that this LBA possesses an obscured AGN (MBH ~ E5-E7 M_sun). While weak AGN may co-exist with the starbursts as shown in at least one of the LBAs, their contribution to the total radio flux is fairly minimal. Our results show that the detection of such weak AGN presents a challenge at radio, X-ray and optical emission-line wavelengths at z ~ 0.2, indicating the great difficulties that need to be overcome in order to study similar processes at high redshift when these types of galaxies were common.Comment: 10 pages, 4 figures, accepted for publication in MNRA

Use of molecular modelling to probe the mechanism of the nucleoside transporter NupG.

Nucleosides play key roles in biology as precursors for salvage pathways of nucleotide synthesis. Prokaryotes import nucleosides across the cytoplasmic membrane by proton- or sodium-driven transporters belonging to the Concentrative Nucleoside Transporter (CNT) family or the Nucleoside:H(+) Symporter (NHS) family of the Major Facilitator Superfamily. The high resolution structure of a CNT from Vibrio cholerae has recently been determined, but no similar structural information is available for the NHS family. To gain a better understanding of the molecular mechanism of nucleoside transport, in the present study the structures of two conformations of the archetypical NHS transporter NupG from Escherichia coli were modelled on the inward- and outward-facing conformations of the lactose transporter LacY from E. coli, a member of the Oligosaccharide:H(+) Symporter (OHS) family. Sequence alignment of these distantly related proteins (∼ 10% sequence identity), was facilitated by comparison of the patterns of residue conservation within the NHS and OHS families. Despite the low sequence similarity, the accessibilities of endogenous and introduced cysteine residues to thiol reagents were found to be consistent with the predictions of the models, supporting their validity. For example C358, located within the predicted nucleoside binding site, was shown to be responsible for the sensitivity of NupG to inhibition by p-chloromercuribenzene sulphonate. Functional analysis of mutants in residues predicted by the models to be involved in the translocation mechanism, including Q261, E264 and N228, supported the hypothesis that they play important roles, and suggested that the transport mechanisms of NupG and LacY, while different, share common features