E. Coli Methods and Protocols M E T H O D S I N M O L E C U L a R B I O L O G Y
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Pathological and Therapeutic Approach to Endotoxin-Secreting Bacteria Involved in Periodontal Disease
toxins Review Pathological and Therapeutic Approach to Endotoxin-Secreting Bacteria Involved in Periodontal Disease Rosalia Marcano 1, M. Ángeles Rojo 2 , Damián Cordoba-Diaz 3 and Manuel Garrosa 1,* 1 Department of Cell Biology, Histology and Pharmacology, Faculty of Medicine and INCYL, University of Valladolid, 47005 Valladolid, Spain; [email protected] 2 Area of Experimental Sciences, Miguel de Cervantes European University, 47012 Valladolid, Spain; [email protected] 3 Area of Pharmaceutics and Food Technology, Faculty of Pharmacy, and IUFI, Complutense University of Madrid, 28040 Madrid, Spain; [email protected] * Correspondence: [email protected] Abstract: It is widely recognized that periodontal disease is an inflammatory entity of infectious origin, in which the immune activation of the host leads to the destruction of the supporting tissues of the tooth. Periodontal pathogenic bacteria like Porphyromonas gingivalis, that belongs to the complex net of oral microflora, exhibits a toxicogenic potential by releasing endotoxins, which are the lipopolysaccharide component (LPS) available in the outer cell wall of Gram-negative bacteria. Endotoxins are released into the tissues causing damage after the cell is lysed. There are three well-defined regions in the LPS: one of them, the lipid A, has a lipidic nature, and the other two, the Core and the O-antigen, have a glycosidic nature, all of them with independent and synergistic functions. Lipid A is the “bioactive center” of LPS, responsible for its toxicity, and shows great variability along bacteria. In general, endotoxins have specific receptors at the cells, causing a wide immunoinflammatory response by inducing the release of pro-inflammatory cytokines and the production of matrix metalloproteinases. -
Fall Fiber Festival 2019 Schedule of Events
Fall Fiber Festival 2019 Schedule of Events Ongoing Activities Saturday and Sunday Montpelier Sheep Dog Trials, sponsored by the VA Border Collie Association Skein, Garment & Fiber Arts Competition and Display - Display & Demo Tent Fiber Arts Demonstrations and Hands-on Activities - Display & Demo Tent Fleece Sale - Fleece Sale Tent Saturday October 5, 2019, 10 am – 5 pm ALL DAY Weaving & Spinning Demos, Fiber Prep & Combing, Knit/Crochet Help, Circular Sock Knitting Machines, Yarn/Ball Winding ~ Display & Demo Tent 9:30 am-4:30 pm FELTING WORKSHOP: Felted Necklace ~ Workshop Tents 9:30 am-12:30 pm SPINNING WORKSHOP: Interaction of Color in Spinning ~ Workshop Tents 10 am-4 pm FACE PAINTING ~ Near Animal Exhibit Tent 10 am-4:30 pm DEMO: Circular Sock Knitting Machines ~ Display & Demo Tent 10 am-4:30 pm DEMO: Spinning from a Bunny ~ Display & Demo Tent 10 am-Noon DEMO: Knitting on a Knitting Machine ~ Display & Demo Tent 10 am-11am DEMO: Spinning Shetland Fleece ~ Display & Demo Tent 10:30 am-Noon DEMO: Embroidery & Stitching ~ Display & Demo Tent 11:00 am SHEEP SHEARING ~ Animal Exhibit Tent 11 am-1 pm DEMO: Great Wheel Spinning (Weather Permitting) ~ Display & Demo Tent 11 am-Noon DEMO: Combing Wool for Worsted Spinning ~ Display & Demo Tent 11 am-1 pm DEMO: Nuno Felting ~ Display & Demo Tent 12:30 pm-2 pm DEMO: Tri-Loom Weaving ~ Display & Demo Tent 1 pm-4 pm DEMO: Needle Felted Flowers - Ginter Garden Felters ~ Display & Demo Tent 1 pm-2:30 pm DEMO: Kumihimo Braiding ~ Display & Demo Tent 1 pm-2 pm KIDS CLASS: Walk in Projects for -
Methylase-Assisted Subcloning for High Throughput Biobrick Assembly
Methylase-assisted subcloning for high throughput BioBrick assembly Ichiro Matsumura Emory University School of Medicine, Department of Biochemistry, Atlanta, GA, United States of America ABSTRACT The BioBrick standard makes possible iterated pairwise assembly of cloned parts with- out any depletion of unique restriction sites. Every part that conforms to the standard is compatible with every other part, thereby fostering a worldwide user community. The assembly methods, however, are labor intensive or inefficient compared to some newer ones so the standard may be falling out of favor. An easier way to assemble BioBricks is described herein. Plasmids encoding BioBrick parts are purified from Escherichia coli cells that express a foreign site-specific DNA methyltransferase, so that each is subsequently protected in vitro from the activity of a particular restriction endonuclease. Each plasmid is double-digested and all resulting restriction fragments are ligated together without gel purification. The ligation products are subsequently double-digested with another pair of restriction endonucleases so only the desired insert-recipient vector construct retains the capacity to transform E. coli. This 4R/2M BioBrick assembly protocol is more efficient and accurate than established workflows including 3A assembly. It is also much easier than gel purification to miniaturize, automate and perform more assembly reactions in parallel. As such, it should streamline DNA assembly for the existing community of BioBrick users, and possibly encourage others to join. Subjects Bioengineering, Molecular Biology, Synthetic Biology Keywords BioBrick assembly, Methylase-assisted cloning, Synthetic biology, Laboratory automation, DNA methyltransferase Submitted 27 April 2020 Accepted 10 August 2020 Published 11 September 2020 INTRODUCTION Corresponding author A bottleneck in many synthetic biology projects is the physical linkage of cloned synthetic Ichiro Matsumura, [email protected] genes (``parts'') to each other to form longer functional assemblies (``devices''). -
Solutions for Practice Problems for Molecular Biology, Session 5
Solutions to Practice Problems for Molecular Biology, Session 5: Gene Regulation and the Lac Operon Question 1 a) How does lactose (allolactose) promote transcription of LacZ? 1) Lactose binds to the polymerase and increases efficiency. 2) Lactose binds to a repressor protein, and alters its conformation to prevent it from binding to the DNA and interfering with the binding of RNA polymerase. 3) Lactose binds to an activator protein, which can then help the RNA polymerase bind to the promoter and begin transcription. 4) Lactose prevents premature termination of transcription by directly binding to and bending the DNA. Solution: 2) Lactose binds to a repressor protein, and alters its conformation to prevent it from binding to the DNA and interfering with the binding of RNA polymerase. b) What molecule is used to signal low glucose levels to the Lac operon regulatory system? 1) Cyclic AMP 2) Calcium 3) Lactose 4) Pyruvate Solution: 1) Cyclic AMP. Question 2 You design a summer class where you recreate experiments studying the lac operon in E. coli (see schematic below). In your experiments, the activity of the enzyme b-galactosidase (β -gal) is measured by including X-gal and IPTG in the growth media. X-gal is a lactose analog that turns blue when metabolisize by b-gal, but it does not induce the lac operon. IPTG is an inducer of the lac operon but is not metabolized by b-gal. I O lacZ Plac Binding site for CAP Pi Gene encoding β-gal Promoter for activator protein Repressor (I) a) Which of the following would you expect to bind to β-galactosidase? Circle all that apply. -
Instability of Toxin a Subunit of AB5 Toxins in the Bacterial Periplasm Caused by Deficiency of Their Cognate B Subunits
Biochimica et Biophysica Acta 1808 (2011) 2359–2365 Contents lists available at ScienceDirect Biochimica et Biophysica Acta journal homepage: www.elsevier.com/locate/bbamem Instability of toxin A subunit of AB5 toxins in the bacterial periplasm caused by deficiency of their cognate B subunits Sang-Hyun Kim a, Su Hyang Ryu a, Sang-Ho Lee a, Yong-Hoon Lee a, Sang-Rae Lee a, Jae-Won Huh a, Sun-Uk Kim a, Ekyune Kim d, Sunghyun Kim b, Sangyong Jon b, Russell E. Bishop c,⁎, Kyu-Tae Chang a,⁎⁎ a The National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Chungbuk 363–883, Republic of Korea b School of Life Science, Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Gwangju 500–712, Republic of Korea c Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada L8N 3Z5 d College of Pharmacy, Catholic University of Daegu, Hayang-eup, Gyeongsan, Gyeongbuk 712-702, Republic of Korea article info abstract Article history: Shiga toxin (STx) belongs to the AB5 toxin family and is transiently localized in the periplasm before secretion Received 26 April 2011 into the extracellular milieu. While producing outer membrane vesicles (OMVs) containing only A subunit of Received in revised form 3 June 2011 the toxin (STxA), we created specific STx1B- and STx2B-deficient mutants of E. coli O157:H7. Surprisingly, Accepted 23 June 2011 STxA subunit was absent in the OMVs and periplasm of the STxB-deficient mutants. In parallel, the A subunit Available online 5 July 2011 of heat-labile toxin (LT) of enterotoxigenic E. -
Mycotoxin Analysis in Infant Formula Using Captiva EMR-Lipid
Application Note Food Testing & Agriculture Mycotoxin Analysis in Infant Formula Using Captiva EMR—Lipid Cleanup and LC/MS/MS Author Abstract Derick Lucas Agilent Technologies, Inc. Several countries regulate the levels of mycotoxins in foods. However, the complexity of certain foodstuffs in terms of protein and lipid content can prove challenging in the accurate quantitation of low-level mycotoxins in these matrices. This Application Note describes the determination of 13 multiclass mycotoxins in solid and liquid infant formulations using a Quick Easy Cheap Effective Rugged Safe (QuEChERS) workflow followed by Agilent Captiva EMR—Lipid cartridge cleanup. Due to the high selectivity of the Captiva EMR—Lipid sorbent, excellent recoveries (70.4 to 106.8 %) and precision (<18 %) were achieved for all mycotoxins. This simple and robust methodology requires minimal equipment and expertise, which promotes easy implementation in food laboratories. Introduction Experimental Mycotoxins are produced as secondary metabolites by fungal Sample preparation species that grow on various crops such as grain, corn, and • Captiva EMR—Lipid 3-mL tubes (p/n 5190-1003) nuts. When cows ingest contaminated feed, mycotoxins and their metabolites can be excreted into the animal’s milk1. • Captiva EMR—Lipid 6-mL tubes (p/n 5190-1004) Aflatoxin M1 is the most commonly found mycotoxin in milk, • QuEChERS original extraction salts (p/n 5982-5550) and is monitored and regulated in many countries, including • VacElut SPS 24 vacuum manifold (p/n 12234022) the United States and European countries2,3. Despite a lack of regulations for other mycotoxins in milk, there is a growing LC configuration and parameters interest to monitor additional mycotoxins such as fumonisins and ochratoxins. -
The Lactose Operon from Lactobacillus Casei Is Involved in the Transport
www.nature.com/scientificreports OPEN The lactose operon from Lactobacillus casei is involved in the transport and metabolism of the Received: 4 October 2017 Accepted: 26 April 2018 human milk oligosaccharide core-2 Published: xx xx xxxx N-acetyllactosamine Gonzalo N. Bidart1, Jesús Rodríguez-Díaz 2, Gaspar Pérez-Martínez1 & María J. Yebra1 The lactose operon (lacTEGF) from Lactobacillus casei strain BL23 has been previously studied. The lacT gene codes for a transcriptional antiterminator, lacE and lacF for the lactose-specifc phosphoenolpyruvate: phosphotransferase system (PTSLac) EIICB and EIIA domains, respectively, and lacG for the phospho-β-galactosidase. In this work, we have shown that L. casei is able to metabolize N-acetyllactosamine (LacNAc), a disaccharide present at human milk and intestinal mucosa. The mutant strains BL153 (lacE) and BL155 (lacF) were defective in LacNAc utilization, indicating that the EIICB and EIIA of the PTSLac are involved in the uptake of LacNAc in addition to lactose. Inactivation of lacG abolishes the growth of L. casei in both disaccharides and analysis of LacG activity showed a high selectivity toward phosphorylated compounds, suggesting that LacG is necessary for the hydrolysis of the intracellular phosphorylated lactose and LacNAc. L. casei (lacAB) strain defcient in galactose-6P isomerase showed a growth rate in lactose (0.0293 ± 0.0014 h−1) and in LacNAc (0.0307 ± 0.0009 h−1) signifcantly lower than the wild-type (0.1010 ± 0.0006 h−1 and 0.0522 ± 0.0005 h−1, respectively), indicating that their galactose moiety is catabolized through the tagatose-6P pathway. Transcriptional analysis showed induction levels of the lac genes ranged from 130 to 320–fold in LacNAc and from 100 to 200–fold in lactose, compared to cells growing in glucose. -
Impact of Bacterial Toxins in the Lungs
toxins Review Impact of Bacterial Toxins in the Lungs 1,2,3, , 4,5, 3 2 Rudolf Lucas * y, Yalda Hadizamani y, Joyce Gonzales , Boris Gorshkov , Thomas Bodmer 6, Yves Berthiaume 7, Ueli Moehrlen 8, Hartmut Lode 9, Hanno Huwer 10, Martina Hudel 11, Mobarak Abu Mraheil 11, Haroldo Alfredo Flores Toque 1,2, 11 4,5,12,13, , Trinad Chakraborty and Jürg Hamacher * y 1 Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA; hfl[email protected] 2 Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA; [email protected] 3 Department of Medicine and Division of Pulmonary Critical Care Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA; [email protected] 4 Lungen-und Atmungsstiftung, Bern, 3012 Bern, Switzerland; [email protected] 5 Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, 3012 Bern, Switzerland 6 Labormedizinisches Zentrum Dr. Risch, Waldeggstr. 37 CH-3097 Liebefeld, Switzerland; [email protected] 7 Department of Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada; [email protected] 8 Pediatric Surgery, University Children’s Hospital, Zürich, Steinwiesstrasse 75, CH-8032 Zürch, Switzerland; [email protected] 9 Insitut für klinische Pharmakologie, Charité, Universitätsklinikum Berlin, Reichsstrasse 2, D-14052 Berlin, Germany; [email protected] 10 Department of Cardiothoracic Surgery, Voelklingen Heart Center, 66333 -
Lucet Braiding
Lucet Braiding A lucet is a simple 2 pronged device used during the Middle Ages (and earlier and later) for making cords. It is most often associated with the Viking Era but were used through out Europe. It makes a strong either square or flat cord. Lucets were made of horn, bone or wood. The cords, also called chains, were used as drawstrings in clothing and bags or purses. They were also used ornamentally as trim on clothing and other items and to hang items from belts. Larger versions of these cords were probably also used by sailors. Making Your Own Lucet A lucet can be made from any 2 pronged item. My first lucet was a plastic 2 pronged fork. My second lucet was a large wooden fork with the center prongs removed. The lyre shape can be cut out of 1/4 inch wood such as pine or oak and then the edges sanded. Basic Square Cord Crochet thread or thin yarn is good for beginners to start with. 1. Drop a 6 inch tail of the thread through the hole going from front to back. If your lucet doesn't have a hole, it is not a problem, just pull the tail around to the back of the lucet. 2. Holding the lucet in your left hand with the thumb holding the tail in place above the hole, wind the thread as shown: front to back on the right arm, then front to back on the left arm and then front to back on the right arm again, making a "figure 8." The thread should now be on teh back side where you can hold it between two fingers to keep it snug around the arms. -
A New Biobrick Assembly Strategy Designed for Facile Protein Engineering
A New Biobrick Assembly Strategy Designed for Facile Protein Engineering Ira E. Phillips∗ and Pamela A. Silver∗ April 18, 2006 Abstract The existing biobrick assembly technique[1] provides a straightforward way to combine standardized biological components, termed biobricks. This system, however, is limited in that each protein-encoding biobrick must contain a complete translated region. Signal sequences or other pro- tein domains often convey a specific function to the protein to which they are attached; hence, each domain should be considered an independent biological part. With the current assembly technique, assembling such parts is not possible. This paper presents a revised assembly strategy that is compatible with the current biobrick definition and permits the construction of fusion proteins. Introduction The standard biobrick assembly technique was created in an attempt to simplify the construction of long concatemeric pieces of DNA often used in synthetic biology [1]. Previously existing techniques were limiting in that one often needed to design a unique cloning strategy for each desired construct. Moreover, the intermediates in the cloning of one construct would be of little value in creating other constructs. As a solution to these problems, T. Knight developed a novel cloning strategy that permits standardization of biological parts or biobricks [1]. Each biobrick can be placed in front of or behind another biobrick using a standard protocol that is independent of the content of the parts involved. (To insert a biobrick in front of another, simply digest the upstream biobrick with EcoRI and SpeI. Cut out this insert and ligate into a vector containing the second part cut with EcoRI and XbaI. -
Area # 1 Area #2
Area # 1 Black Sheep Handweavers Guild 2-Clip Fringe Twister Knit Wits Kit for Making a Stuffed Penguin, including the Double Point Needles 3 Skeins of Yarn Glenna Harris Weavers’ Guild 1 Boat shuttle 1 Heddle maker 4 Balls Boucle’ Yarn, Beige 1) 1 oz. Bag of White Corriedale Roving 5 Bags Multicolor Roving, from 1 oz. - 5 ozs. Carmel Crafts Guild Harrisville Design Boat Shuttle 6 Wooden Bobbins Area #2 Del Oro Spinners & Weavers Guild Assorted yarns Bucilla Spice, 14) 1.75 oz. Skeins Bernat Fabri, 5) 2 oz. Skeins (600 yds. Ea.) 4 Burgundy, 1 Grey Peaches and Cream - 1 lb. Cone 4 Ply Cotton (Emerald Forest) Knitting Books - H ip to K n it by Judith Swartz & Tops to Toes edited by Kara Gott Warner Whole Rambouillet/Cormo fleece (unwashed) 6.5 pounds, 3.5" to 4" Staple Length Golden Valley Weavers and Spinnters 2 DVD’s - A rtists G u ide to Color an d D ou blew eave P ick u p Mother Lode Weavers and Spinners Our fiber basket is almost exclusively filled with fiber donated by fiber ranchers in Tuolumne and Calaveras Counties. The MLW&S Guild is fortunate to include a versatile range of fiber artists & ranchers. We wish to take this opportunity to thank all of our vendors for their generous donations to this basket. The fiber basket also includes a book, written and donated by Peggy Huth, about a little sheep named Bummer (a true story). The book is a sweet story with heartfelt illustrations that will delight children of all ages. -
Host-Based Lipid Inflammation Drives Pathogenesis in Francisella Infection
Host-based lipid inflammation drives pathogenesis in Francisella infection Alison J. Scotta, Julia Maria Postb, Raissa Lernerb, Shane R. Ellisc, Joshua Liebermand, Kari Ann Shireye, Ron M. A. Heerenc, Laura Bindilab, and Robert K. Ernsta,1 aDepartment of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD 21201; bLaboratory for Eicosanoids and Endocannabinoids, Johannes Gutenberg University Mainz, 55099 Mainz, Germany; cMaastricht MultiModal Molecular Imaging Institute, Maastricht University, 6229 ER Maastricht, The Netherlands; dDepartment of Pathology, University of Washington Medical Center, Seattle, WA 98118; and eDepartment of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, MD 21201 Edited by Roy Curtiss III, University of Florida, Gainesville, FL, and approved October 16, 2017 (received for review July 19, 2017) Mass spectrometry imaging (MSI) was used to elucidate host lipids MSI (18), although other ionization methods [such as desorption involved in the inflammatory signaling pathway generated at the electrospray ionization (DESI) and liquid extraction surface host–pathogen interface during a septic bacterial infection. Using analysis (LESA), and others] are also employed. MSI has been Francisella novicida as a model organism, a bacterial lipid virulence used in a wide array of applications ranging from fingerprint factor (endotoxin) was imaged and identified along with host phos- analysis to mapping drug distribution in tissue. MSI studies of pholipids involved in the splenic response in murine tissues. Here, cancer biology for biomarker discovery, therapeutic target iden- we demonstrate detection and distribution of endotoxin in a lethal tification, and fundamental pathology hold particular promise. In murine F. novicida infection model, in addition to determining the contrast, comparatively few systematic studies have leveraged MSI – temporally and spatially resolved innate lipid inflammatory response to describe the host microbe relationship (19, 20).