DOCSLIB.ORG

The Bdellovibrio Bacteriovorus Twin-Arginine Transport System Has Roles in Predatory and Prey-Independent Growth

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Bdellovibrio Bacteriovorus Twin-Arginine Transport System Has Roles in Predatory and Prey-Independent Growth Microbiology (2011), 157, 3079–3093 DOI 10.1099/mic.0.052449-0 The Bdellovibrio bacteriovorus twin-arginine transport system has roles in predatory and prey-independent growth Chien-Yi Chang,1 Laura Hobley,1 Rob Till,1 Michael Capeness,1 Machi Kanna,23 William Burtt,1 Pratik Jagtap,34 Shin-Ichi Aizawa2 and R. Elizabeth Sockett1 Correspondence 1Institute of Genetics, School of Biology, University of Nottingham Medical School, R. Elizabeth Sockett Nottingham NG7 2UH, UK [email protected] 2Prefectural University of Hiroshima, 562 Nanatsuka, Shobara, Hiroshima 727-0023, Japan 3Max-Planck Institute for Developmental Biology, 72076 Tu¨bingen, Germany Bdellovibrio bacteriovorus grows in one of two ways: either (i) predatorily [in a host-dependent (HD) manner], when it invades the periplasm of another Gram-negative bacterium, exporting into the prey co-ordinated waves of soluble enzymes using the prey cell contents for growth; or (ii) in a host-independent (HI) manner, when it grows (slowly) axenically in rich media. Periplasmic invasion potentially exposes B. bacteriovorus to extremes of pH and exposes the need to scavenge electron donors from prey electron transport components by synthesis of metalloenzymes. The twin-arginine transport system (Tat) in other bacteria transports folded metalloenzymes and the B. bacteriovorus genome encodes 21 potential Tat-transported substrates and Tat transporter proteins TatA1, TatA2 and TatBC. GFP tagging of the Tat signal peptide from Bd1802, a high-potential iron–sulfur protein (HiPIP), revealed it to be exported into the prey bacterium during predatory growth. Mutagenesis showed that the B. bacteriovorus tatA2 and tatC gene products are essential for both HI and HD growth, despite the fact that they partially complement (in SDS resistance assays) the corresponding mutations in Escherichia coli where neither TatA nor TatC are essential for life. The essentiality of B. bacteriovorus TatA2 was surprising given that the B. bacteriovorus genome encodes a second tatA homologue, tatA1. Transcription of tatA1 was found to be induced upon entry to the bdelloplast, and insertional inactivation of tatA1 showed that it significantly slowed the rates of both HI and HD growth. Received 22 June 2011 B. bacteriovorus is one of a few bacterial species that are reliant on a functional Tat system and Revised 24 August 2011 where deletion of a single tatA1 gene causes a significant growth defect(s), despite the presence Accepted 1 September 2011 of its tatA2 homologue. INTRODUCTION system in bacteria have a consensus twin arginine motif S/T-R-R-X-F-L-K (where X is any polar amino acid), a The twin-arginine translocation (Tat) system transports hydrophobic region and an A-x-A cleavage recognition folded proteins across the cytoplasmic membrane and is motif in their N-terminal leading sequence (Berks, 1996; found in a wide variety of bacteria, whilst homologous Stanley et al., 2000). Tat-transported proteins are typically systems are found in both archaea and eukaryotes (Sargent, involved in metabolism, redox reactions, metal acquisition 2007a; Yuan et al., 2010). Proteins transported by the Tat and cell envelope maintenance (Berks et al., 2005; Palmer et al., 2005) and are involved in pathogenesis, symbiosis, 3Present address: Faculty of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima-shi, Hiroshima 739-8527, Japan. quorum sensing and motility (Sargent, 2007a; Stevenson et al., 2007). 4Present address: Minnesota Supercomputing Institute, University of Minnesota, 117 Pleasant Street SE, Minneapolis, MN 55455, USA. In Escherichia coli, a functional Tat system consists of Abbreviations: eGFP, enhanced GFP; HD, host-dependent; HI, host- TatABC (the genes for which are encoded in an operon) independent. and the TatA homologue TatE (Sargent et al., 1998; Weiner Two supplementary tables and two supplementary figures are available et al., 1998). TatB and TatC form a complex in E. coli with the online version of this paper. (Bolhuis et al., 2001) which recognizes the signal motif of a Downloaded from www.microbiologyresearch.org by 052449 G 2011 SGM Printed in Great Britain 3079 IP: 54.70.40.11 On: Mon, 15 Oct 2018 23:12:00 C.-Y. Chang and others Tat substrate, whereupon the TatA proteins associate to systems is higher than for other free-living bacteria. A form a channel complex of 12–35 monomers, associated systematic review by Barabote et al. (2007) predicted at with TatBC (Alami et al., 2003; Dabney-Smith et al., 2006; least four types of cytoplasmic membrane transportation Gohlke et al., 2005; Holzapfel et al., 2007). The Tat systems and five types of outer membrane secretion systems. substrate is transported across the membrane via the TatA Genes encoding the Tat system have been predicted in the channel and released by proteolytic cleavage at the B. bacteriovorus genome (Barabote et al., 2007; Rendulic C-terminal end of the signal peptide. TatA then disas- et al., 2004), including tatB and tatC as well as two tatA sociates from the TatBC complex to reset the process homologues. In this study we show that B. bacteriovorus (Berks et al., 2005; Lee et al., 2006; Sargent, 2007a). Un- or expresses a functional Tat system required for both mis-folded proteins are rejected then targeted for either predatory [prey/host-dependent (HD)] and axenic [prey/ degradation or refolding (DeLisa et al., 2002; Lee et al., host-independent (HI)] growth and that at least one protein 2006; Sargent, 2007a). containing a Tat signal motif is exported from B. bacteriovorus into the cytoplasm of the prey bdelloplast Deletion of tatC in E. coli abolishes Tat system function during predatory growth. We show that deletion of tatA1 (Bogsch et al., 1998) and whilst TatA and TatB share 25 % slows both predatory and axenic growth, delays gene sequence identity, each is essential for full Tat function, expression of some potential Tat substrates and stops the suggesting that they play different roles (Sargent et al., export of Tat substrate protein Bd1802 into the prey during 2001). Alterations in the E. coli TatA protein sequence predation. This shows that B. bacteriovorus TatA1 and TatA2 allow it to function as both TatA and TatB in a TatBE are not interchangeable and are responsible for the transport deletion strain (Blaudeck et al., 2005). TatE has 60 % of different substrates, and that Tat-transported substrates identity with TatA (Lee et al., 2006) and in aerobically can be further exported beyond the B. bacteriovorus outer grown E. coli, tatE is expressed at very low levels compared membrane into the surrounding bdelloplast, possibly with tatA and the deletion of tatE has no noticeable effect contributing to predatory processes. on Tat substrate transport or viability of planktonically grown cells (Jack et al., 2001). However, in E. coli biofilms, tatE transcription is induced up to 2.12 times more than in METHODS planktonic cultures (Beloin et al., 2004). Only in an E. coli tatA tatE double mutant was the Tat pathway blocked in all Bacterial strains, plasmids and culture conditions. All bacterial conditions (Sargent et al., 1998); but TatE in Pseudomonas strains and plasmids used and created in this study are listed in Supplementary Table S1 (available with the online version of this stutzeri is specifically required to transport proteins for paper). E. coli strains were grown in yeast extract and tryptone (YT) denitrification (Heikkila¨ et al., 2001). This and other broth (Lambert & Sockett, 2008) at 29 uC with shaking at 200 r.p.m. studies suggest that second TatA homologues (TatEs), in for 16 h to give late-exponential-phase cultures for use as prey. E. coli diverse bacteria, play an important role in transportation tat mutants containing expression plasmids were grown in the 2 under certain growth conditions (Bru¨ser, 2007). presence of 50 ml ampicillin ml 1 and 100 nM IPTG. E. coli S17-1 (Simon et al., 1983) was routinely used as prey for growth of B. Bdellovibrio bacteriovorus (Stolp & Starr, 1963) is a small bacteriovorus in predatory cultures at 29 uC with shaking at 200 r.p.m. Gram-negative bacterium which preys upon other Gram- (Hobley et al., 2006), which typically contained 50 ml Ca/HEPES negative bacteria. B. bacteriovorus attaches to, penetrates buffer (2 mM CaCl2, 25 mM HEPES pH 7.6), 3 ml of a late- through the outer layers of and grows within the periplasm exponential-phase E. coli culture and 1 ml of a B. bacteriovorus predatory culture (which had completed prey lysis and contained of prey bacteria. B. bacteriovorus modifies the prey cell wall typically 2.56108 p.f.u. ml21). Antibiotic-resistant insertion-mutant B. forming an osmotically stable structure called the bdello- bacteriovorus were grown with E. coli S17-1 carrying an appropriate plast, which is bounded by an intact prey outer membrane. plasmid as prey with the antibiotics at the following concentrations: Inside this, B. bacteriovorus delivers enzymes both to the kanamycin sulphate, 50 mgml21, S17-1 pZMR100 (Rogers et al., 1986); 2 prey periplasm and (at early stages of predation) via the apramycin sulphate, 50 mgml 1, S17-1 pUC19:apraR; both antibiotics, (still intact) prey cell inner membrane to the cytoplasm to S17-1 pLH003. HI derivatives of B. bacteriovorus strains were isolated and grown at 29 uC on peptone and yeast extract (PY) plates or in PY degrade the cytoplasmic contents of the prey cell. Prey- broth with shaking at 200 r.p.m. as described previously (Evans et al., derived nutrients facilitate B. bacteriovorus growth and 2007; Shilo & Bruff, 1965). reproduction and B. bacteriovorus elongates into a filamen- tous cell. After consuming the bdelloplast interior, the B. bacteriovorus predation assays using E. coli MC4100 and filament divides into multiple progeny B. bacteriovorus B1LK0-P (DtatC) as prey. E. coli strains MC4100 (Casadaban & which become flagellate and escape through the bdelloplast Cohen, 1979) and B1LK0-P (Buchanan et al., 2002) were grown as outer membrane to carry out further predation (Sockett, described above to late exponential phase, then diluted (in cell-free supernatant from the same cultures) and matched to OD600 1.5.
Load more

Recommended publications
  • 1471-2164-13-670.Pdf
    Hobley et al. BMC Genomics 2012, 13:670 http://www.biomedcentral.com/1471-2164/13/670 RESEARCH ARTICLE Open Access Genome analysis of a simultaneously predatory and prey-independent, novel Bdellovibrio bacteriovorus from the River Tiber, supports in silico predictions of both ancient and recent lateral gene transfer from diverse bacteria Laura Hobley1,3, Thomas R Lerner1,4, Laura E Williams2, Carey Lambert1, Rob Till1, David S Milner1, Sarah M Basford1, Michael J Capeness1, Andrew K Fenton1,5, Robert J Atterbury1,6, Maximilian ATS Harris1 and R Elizabeth Sockett1* Abstract Background: Evolution equipped Bdellovibrio bacteriovorus predatory bacteria to invade other bacteria, digesting and replicating, sealed within them thus preventing nutrient-sharing with organisms in the surrounding environment. Bdellovibrio were previously described as “obligate predators” because only by mutations, often in gene bd0108, are 1 in ~1x107 of predatory lab strains of Bdellovibrio converted to prey-independent growth. A previous genomic analysis of B. bacteriovorus strain HD100 suggested that predatory consumption of prey DNA by lytic enzymes made Bdellovibrio less likely than other bacteria to acquire DNA by lateral gene transfer (LGT). However the Doolittle and Pan groups predicted, in silico, both ancient and recent lateral gene transfer into the B. bacteriovorus HD100 genome. Results: To test these predictions, we isolated a predatory bacterium from the River Tiber- a good potential source of LGT as it is rich in diverse bacteria and organic pollutants- by enrichment culturing with E. coli prey cells. The isolate was identified as B. bacteriovorus and named as strain Tiberius. Unusually, this Tiberius strain showed simultaneous prey-independent growth on organic nutrients and predatory growth on live prey.
    [Show full text]
  • An Inside Job: Bdellovibrio Bacteriovorus Some Predatory ‘Bugs’ Eat Other ‘Bugs’ from Inside, As Liz Sockett and Her Research Group Have Found
    An inside job: Bdellovibrio bacteriovorus Some predatory ‘bugs’ eat other ‘bugs’ from inside, as Liz Sockett and her research group have found. dellovibrio are small (0.25× Bdellovibrio where the acquisition of a large number of genes periplasmic growth phase, during which they reside inside the 1.0 µm), flagellate, motile, for hydrolytic enzymes, and for penetrating and resealing dead prey cell, degrading it by secreting enzymes across the Gram-negative deltapro- the prey cell, give access to an intracellular niche, bounded prey cytoplasmic membrane to digest prey macromolecules, teobacteria which invade by the prey-cell outer membrane, where the Bdellovibrio can and taking up the products for Bdellovibrio growth. Bdellovibrio and kill other Gram-nega- ‘dine privately’ on the inner contents of the prey cell without seem to be mostly ‘locked on’ to predatory growth in dilute tive bacteria, entering the competition for nutrients from other bacteria. This contrasts environments and cannot productively switch to HI growth to Bprey cell’s periplasm, replicating within with the ‘eating habits’ of other deltaproteobacteria such survive, but depend on finding prey for replication. During the it and using the contents of that as the myxobacteria which digest prey externally and take free-swimming attack phase, rapid prey location, attachment bacterium as their nutrient source. up digested prey nutrients partly in competition with other and recognition are vital to the successful replication of the Bdellovibrio bacteriovorus HD100 is the bacteria in their surroundings. Bdellovibrio, as they typically have a half-life of about 10 sequenced strain and has a 3.8 Mb gen- hours during starvation in buffered environments.
    [Show full text]
  • Microbiology@UCL Virtual Symposium 2020
    Microbiology@UCL Virtual Symposium 2020 Day 1: 28th July 9:00 – 12:30 08:50 – 09:00 Welcome and housekeeping (opening slides) 09:00 Opening: Joanne Santini (Structural & Molecular Biology and Domain lead) Session 1 (Chair: Snezana Djordjevic, Structural & Molecular Biology) 09:05 Keynote: Rotem Sorek (Weizmann Institute of Science) The immune system of bacteria: Beyond CRISPR 09:35 Mark Marsh (MRC Laboratory for Molecular Cell Biology) Membrane trafficking plays an essential role in lentiviral pathogenesis 09:50 George Blundell-Hunter (Pharmaceutics) Characterisation of bacteriophage-encoded depolymerases selective for key Klebsiella pneumoniae capsular exopolysaccharides 09:55 Georgina Benn (London Centre for Nanotechnology and Institute of Structural & Molecular Biology) Imaging the surface of live bacteria with nanometre resolution 10:00 Samuel Ellis (Infection, Immunity & Inflammation, GOSH Institute of Child Health) Impact of binding respiratory syncytial virus G protein on pneumococcal cell division and antibiotic sensitivity 10:05 Poster Session 1 (Chair: China Hanson, Microbiology@UCL Domain Manager) 10:30 Jason Mercer (MRC Laboratory for Molecular Cell Biology) Seeing is believing: Super-resolving poxvirus protein architecture 10:45 15min break Session 2 (Chair: TBA) 11:00 Jürg Bähler (Genetics, Evolution & Environment) Natural variant of pyruvate kinase in fission yeast tunes energy metabolism and triggers systems-wide adaptations in cellular regulation and physiology 11:15 Gabriel Tarrason Risa (MRC Laboratory for Molecular
    [Show full text]
  • Microbiologytoday Biology and Pathogenesis Current Technology and Author: Naveed Khan Molecular Biology Applications
    Caister Academic Press New Books for 2009 www.caister.com Acanthamoeba Lactobacillus Real-Time PCR microbiologytoday Biology and Pathogenesis Current Technology and Author: Naveed Khan Molecular Biology Applications ... available now! c. 220 pp., February 2009 From Genomics to Probiotics Edited by: J. Logan, K. Edwards and N. Saunders ISBN: 978-1-904455-43-1 $310 / £150 Edited by: Åsa Ljungh and Torkel Wadström x + 284 pp., January 2009 The first comprehensive review of c. 220 pp., January 2009 ISBN 978-1-904455-39-4 $310 / £150 Acanthamoeba research to be published. ISBN 978-1-904455-41-7 $310 / £150 A comprehensive guide to the latest PCR The current state of research on every aspect An essential reference for all dairy of this organism, detailing major advances platforms, fluorescent chemistries, validation technologists, microbiologists and in areas such as genomics, molecular and software, data analysis, internal and external cellular biology, life cycles, geographical biotechnologists. Includes phylogenetics, controls and a wide range of applications: distribution, role in ecosystem, morphology, taxonomy, comparative genomics, functional clinical diagnostics, biodefense, RNA vol35|nov08 genomics, the intestinal microflora, surface motility, phylogenetics, genotyping, metabolism, expression studies, validation of array data, quarterly regulation of morphogenesis, host-parasite proteins, stress responses, interaction with mutation detection, food authenticity and interactions, the molecular and immunological the immune system, probiotics, anti-cancer legislation, NASBA, and molecular halotyping. basis of pathogenesis, methods of transmission, potential, and much more. Essential reading for magazine of epidemiology, clinical manifestation, diagnosis, all scientists involved with lactic acid bacteria treatment, new target development and drug or probiotic research and a recommended book the society resistance.
    [Show full text]
  • Researchers Uncover Tools Used by Predatory Bacteria to Escape Unharmed from Prey Cell 23 September 2020
    Researchers uncover tools used by predatory bacteria to escape unharmed from prey cell 23 September 2020 bacteriovorus succeeds in invading, and then escaping its prey cells is an important step in this process. The enzyme they discovered seems like a well- known enzyme called a lysozyme- one of the earliest- ever studied enzymes and found in human tears and saliva; but this one has a twist where it has changed to do something surprising. "Bdellovibrio bacteriovorus is known for its ability to invade prey bacteria and stay inside the cell for a few hours, effectively eating the bacteria alive," explains Dr. Andrew Lovering, of the University of Birmingham's School of Biosciences. "At the end of Credit: CC0 Public Domain this process, the predator is able to break the prey open and escape. Because the walls of both the predator and prey cells are made of very similar molecules, we wanted to find out how the predator Predatory bacteria, capable of invading and was able to cut the cell wall material of the prey cell consuming harmful bugs such as E .coli and and get out without damaging itself in the process." Salmonella, use a unique tool to help them escape the cell they have invaded without harming The team already knew part of the answer lay in an themselves, according to a new study. early action by the predator bacteria to remove a particular molecule, from the cell wall of the prey. Researchers at the Universities of Birmingham and This created a 'marker' identifying the prey wall Nottingham have identified a particular enzyme material as different to the predator.
    [Show full text]
  • Xvii Convention D'autunno Dei Ricercatori in Fibrosi Cistica
    XVII CONVENTION D’AUTUNNO DEI RICERCATORI IN FIBROSI CISTICA 17th Convention of Investigators in Cystic Fibrosis 14-16 November 2019 Verona, Camera di Commercio, Congress Center In collaborazione con Con il patrocinio di Azienda Ospedaliera Universitaria Integrata Verona In copertina / On the cover Presso Ospedale Maggiore B.go Trento P.le A. Stefani, 1 - 37126 Verona Presidenza e Segreteria Tel. 045 8123438 - fax 045 8123568 e-mail: [email protected] Codice fiscale 93100600233 Consiglio di Amministrazione Presidente: Matteo Marzotto Presidente emerito: Vittoriano Faganelli Vice Presidenti: Paolo Faganelli, Michele Romano Consiglieri: Michele Bauli Riccardo Boatto Cesare Braggion Sandro Caffi Francesco Cobello Michele Gangemi Giuseppe Lauria Pinter Giuseppe Magazzù Gianni Mastella Laura Minicucci Patrizia Volpato Direzione Scientifica – Direttore Scientifico: Gianni Mastella Tel. 045 8123567 / e-mail: [email protected] – Vicedirettore Scientifico: Graziella Borgo Un modello di fibrosi cistica in chip microfluidico Tel. 045 8127027 / e-mail: [email protected] – Assistente alla Comunicazione: Flaminia Malvezzi In alto A sinistra.Un circuito microfluidico (chip) sviluppato per la coltura di modelli di tessuti sani Tel. 045 8127027 / [email protected] e tessuti affetti da fibrosi cistica.E’ un dispositivo di dimensioni minime, costituito da una – Assistente all’Organizzazione: Federica Lavarini complessa rete di microcanali che interagiscono con il tessuto coltivato al suo interno. Nel caso Tel. 045 812 7037 / [email protected] della fibrosi cistica il tessuto riproduce le tre componenti di un bronco affetto da FC: cellule epiteliali (che rivestono la sua superficie interna), cellule mucipare (che producono muco) e Comitato di Consulenza Scientifica tessuto connettivale. Il tessuto può essere esposto all’azione di stimoli di varia natura, a batteri patogeni o a farmaci (infusi attraverso i canali o somministrati per aerosol).
    [Show full text]
  • Transmission of Antimicrobial Resistance in Different Settings: Priorities for a Pan- European Multidisciplinary Approach
    Transmission of antimicrobial resistance in different settings: priorities for a Pan- European multidisciplinary approach Hosted by the UK Medical Research Council and the UK Science and Innovation Network in association with the Joint Programming Initiative on Antimicrobial Resistance Delegates Information Pack Monday 12th October 2015 British Embassy, Wilhelmstrasse 70, 10117 Berlin, Germany 1 Contents Workshop Information ........................................................................................... 3 About the MRC ................................................................................................... 4 About the SIN .................................................................................................... 5 About the JPIAMR ............................................................................................... 5 Agenda ................................................................................................................ 7 Background and Delegates Brief .............................................................................. 9 Notes ................................................................................................................. 31 2 Workshop Information Date: Monday 12th October 2015 Time: 10:00 – 16:45 Venue: British Embassy, Wilhelm Strasse 70, 10117 Berlin Security: All visitors to the embassy will have to go through the security checkpoint at the entrance. Please ensure you have photo identification and co-operate with the security team as they conduct
    [Show full text]
  • Nnie Robiologytodoy
    q nnierobiologytodoy 'rol32I cug05 c-4L{!*rri{;rryr-'{rrr-rri"nr$r, rfi#Utrxin* mf $[,r4 ,"4r'irr*r ' li ls bi"Julffi | )i frrrr\/{ r-rsnc*rnltq;l\Jr vq;t rni*r*hlnl*gy :',..,)i"viiil': i lg::::i*lli..... '" i|"r;)i; vcl32(3) I \--...,..1 \...,,1{r....1 : :\... 1 : .i i i.,."rr 102 News 142 Cradline 150 Reviews 136 Meetings 144 Hotoff the press152 obituaries 138 schoolzone146 Coingpublic 1 55 Add resses i-.ri i-ir#r" i i*,r il-i li 121 tRCreport 127 Microbiologyin the Regionsreport {-,ti"fi*jt*s 1 1OAn introduction to virusesand l(illerinto cure - cance r oncolyticviruses DorothyH. Crawford Moira Brown Canceris a major killer.Viruses are involved in 10-20o/oof all Cenetherapy using viruses provides an exciting human casesof this disease. newanti-cancer treatment. 113 Bacteriaincancer th erapy 132Two early'general CarolineSpringer, Panos Lehouritis & micro b io logists' RichardMarais MichaelJ. Carlile Bacteriaare showing great prom isei n new cancertherapies. Manyscientists fled the Nazisin the runup to WWll. Twoof themmade great contributions to Ul( microbiology. Human 134 - papillomavirusesa[d Debate cance r teaching m icrobiology to medical students JulieBurns & DlawerAla'Aldeen NormanMaitland Can problem-oriented teaching produce better doctors? Papillomavirusescause a rangeof cancers,but help isat hand in the form of effectivevaccines. Comment - 122 Nobelmicrobes define the a microbiologist's artofcelldivision viewof astrobiology lainHagan & PaulNurse HowardCest In the fight against cancer, m icrobes are showi ng the way to lsastrobiology really a science?Does it involve our understandingof the controlof celldivision. micro-organisms? {-*u*r irnagc Coloured scanning electron micrograph of a dividing cervical cancer cell.
    [Show full text]
  • Profiling the Predatosome in the Bacterial Pathogen Bdellovibrio
    The First Bite— Profiling the Predatosome in the Bacterial Pathogen Bdellovibrio Carey Lambert, Chien-Yi Chang, Michael J. Capeness, R. Elizabeth Sockett* Institute of Genetics, School of Biology, Nottingham University, Queen’s Medical Centre, Nottingham, United Kingdom Abstract Bdellovibrio bacteriovorus is a Gram-negative bacterium that is a pathogen of other Gram-negative bacteria, including many bacteria which are pathogens of humans, animals and plants. As such Bdellovibrio has potential as a biocontrol agent, or living antibiotic. B. bacteriovorus HD100 has a large genome and it is not yet known which of it encodes the molecular machinery and genetic control of predatory processes. We have tried to fill this knowledge-gap using mixtures of predator and prey mRNAs to monitor changes in Bdellovibrio gene expression at a timepoint of early-stage prey infection and prey killing in comparison to control cultures of predator and prey alone and also in comparison to Bdellovibrio growing axenically (in a prey-or host independent ‘‘HI’’ manner) on artificial media containing peptone and tryptone. From this we have highlighted genes of the early predatosome with predicted roles in prey killing and digestion and have gained insights into possible regulatory mechanisms as Bdellovibrio enter and establish within the prey bdelloplast. Approximately seven percent of all Bdellovibrio genes were significantly up-regulated at 30 minutes of infection- but not in HI growth- implicating the role of these genes in prey digestion. Five percent were down-regulated significantly, implicating their role in free- swimming, attack-phase physiology. This study gives the first post- genomic insight into the predatory process and reveals some of the important genes that Bdellovibrio expresses inside the prey bacterium during the initial attack.
    [Show full text]
  • Bsc Microbiology Degrees in the UK Liz Sockett
    BSc microbiology degrees in the UK Liz Sockett Entering stationary phase? Student recruitment Liz Sockett An interrogation of the UCAS statistics for takes a look at G2001(www.ucas.ac.uk) reveals 199 UK first first degrees in degree programmes that include the word UK universities, ‘microbiology’ in their title, of which 51 are single- subject microbiology degrees. In the remainder analysing the microbiology is offered in combination with subjects recruitment figures including French, German, psychology, computing, and checking food science, immunology and opthalmic dispensing. out their course The range of UK institutions offering these degrees is content. shown in Fig. 1. Some others, not listed, offer micro- biology within biotechnology programmes. Despite the plethora of institutions offering degrees, the total number of students entering bachelors degrees with a C5 microbiology code in the UK is only around 500. As the histogram in Fig. 2 illustrates, this number is similar to that for genetics, but considerably less than for biochemistry, chemistry and biology degrees. As Fig. 2 shows, recruitment to microbiology degrees is approximately one-quarter of that to media studies degrees. If only microbiological media were as attractive as the news media! As can be seen in Fig. 3, recruitment onto micro- biology degrees has remained steady or even slightly increased over the last 5 years with the exception of 2000 over the same 5 year period. The comparative figures where a downturn was experienced. Whether the 2000 for media studies help to explain where those students figure turns out to be an anomaly, only time will tell. The are going.
    [Show full text]
  • The Biologist
    BIOETHICS IMMUNOLOGY BIOENGINEERING ‘ETHICS DUMPING’ IN WHAT’S CAUSING STRANGE COMPUTER-AIDED DESIGN THE LIFE SCIENCES NEW MEAT ALLERGIES? SOFTWARE FOR BIOLOGY THE MAGAZINE OF THE ROYAL SOCIETY OF BIOLOGY /www.rsb.org.uk ISSN 0006-3347 • Vol 66 No 3 • Jun/Jul 19 TURN THE TIDE A blueprint to save marine biodiversity, with Callum Roberts Volume 66 No 3 CONTENTS June/July 2019 HAVE AN IDEA FOR AN ARTICLE OR INTERESTED IN WRITING FOR US? For details contact [email protected] ROYAL SOCIETY OF BIOLOGY 1 Naoroji Street, Islington, London WC1X 0GB Tel: 020 7685 2400 [email protected]; www.rsb.org.uk EDITORIAL STAFF Editor Tom Ireland MRSB @Tom_J_Ireland ON THE COVER [email protected] 12 Interview: Callum Roberts Editorial assistant The marine biologist explains the Emma Wrake AMRSB benefits of using protected areas Chair of the Editorial Board of ocean to boost biodiversity Professor Alison Woollard FRSB Editorial Board Dr Anthony Flemming MRSB, Syngenta Professor Adam Hart FRSB, University of Gloucestershire UP FRONT Dr Sarah Maddocks CBiol MRSB, 26 04 Society News Cardiff Metropolitan University Speaker’s lecture, Teacher Professor Shaun D Pattinson FRSB, Durham University of the Year 2019 and our AGM Dr James Poulter MRSB, University of Leeds 06 Policy and analysis Dr Cristiana P Velloso MRSB, King’s College London The Government’s National Food Strategy, plus Brexit Watch Membership enquiries Tel: 01233 504804 [email protected] FEATURES Subscription enquiries Tel: 020 7685 2556; [email protected] 08 Research review The NC3Rs’ efforts
    [Show full text]
  • Biquarterly Magazine of the Society for General
    BIQUARTERLYMAGAZINE OFTHE SOCIETY FORGENERAL MICROBIOLOGY VOLUME 26MAY 1999 Physicsunder the microscope Taxonomyfor the new millennium Howmolecules cross membranes Let'shave a debate! F SGMHeadquarters MarlborouqhHouse Articles BasinqstolieRoad SpenciersWood Physicsunderthe microscope Dave Roberts 50 ReadinoRG7 1AE It'sallaquestion of image Tet.0flB9BB 1800 Fax 01189885656 Dave Roberts &Gianfranco Novarino 51 e-mailmtoday@ Atomicforce microscopyA lastair socgenmicrobiol.org.uk Smith 54 SGMWebSite Cryo-electronmicroscopy: taking backthe knight http:,/www.socgenmicrobiol.org.uk Stephen Fuller 56 Editor DrDave McL. Roberts Crystal log raphy and the atomic anatomyof viruses DavidL Stuart, Jonathan M. Grimes,Nick Burroughs & Editorial Board DrUlrich Desselberqer Peter P.C.Mertens 59 rrolessoruave Kowtanos Nuclearmagnetic resonance (N M R):keeping pace with ManagingEditor microbiologySte phen Matth ews 62 JanetHurst Produetion Editor Whata Ramanspectrum can tell the microbials6nlnnicl lanAtherton NozomiYtow 64 Assistant Editor and Bacterialclassification and taxonomv: a'orimer' forthe new BookReviewManager millenniumHowardGest JaniceMeekings 70 Gontributions Meetin g preview:Del iveri n g the goodsB ruce Ward 74 Theseare always welcome and shouldb'e addressed to the Editor Let's have a d ebatel Philip Mortimer 77 (c/o SGM Headquarters). GopyDates Lastdates for receipt of copy atMarlborouoh House are: Regular Features LieneralUODV no lnternationalDevelopment Fund reports IZ Augustissue 10 May Novemberissue 1 3 September SocietyNews AOVefttSemen$ (vKU) Above: Partofthe This issue ol M icrob i ol ogy FebruaryCouncil Meeting 80 Auoustissue 7 June structureofthe core of Todaylocuseson biophysics Notices 80 NoVemberissue 1 1 October bluetonguevirus. andthe applicationsthat are NewsofMembers 80 Advertisements relevantto microbiology.lt Photocou rtesy J. Diprose, Staff News BO Allenouiriesshould be senttor includesin-deoth articles on InaCocks,NWH Sales Ltd, J.Grimes,D.
    [Show full text]