Enzymes for Molecular Biology Catalogue
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Introduction of Human Telomerase Reverse Transcriptase to Normal Human Fibroblasts Enhances DNA Repair Capacity
Vol. 10, 2551–2560, April 1, 2004 Clinical Cancer Research 2551 Introduction of Human Telomerase Reverse Transcriptase to Normal Human Fibroblasts Enhances DNA Repair Capacity Ki-Hyuk Shin,1 Mo K. Kang,1 Erica Dicterow,1 INTRODUCTION Ayako Kameta,1 Marcel A. Baluda,1 and Telomerase, which consists of the catalytic protein subunit, No-Hee Park1,2 human telomerase reverse transcriptase (hTERT), the RNA component of telomerase (hTR), and several associated pro- 1School of Dentistry and 2Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California teins, has been primarily associated with maintaining the integ- rity of cellular DNA telomeres in normal cells (1, 2). Telomer- ase activity is correlated with the expression of hTERT, but not ABSTRACT with that of hTR (3, 4). Purpose: From numerous reports on proteins involved The involvement of DNA repair proteins in telomere main- in DNA repair and telomere maintenance that physically tenance has been well documented (5–8). In eukaryotic cells, associate with human telomerase reverse transcriptase nonhomologous end-joining requires a DNA ligase and the (hTERT), we inferred that hTERT/telomerase might play a DNA-activated protein kinase, which is recruited to the DNA role in DNA repair. We investigated this possibility in nor- ends by the DNA-binding protein Ku. Ku binds to hTERT mal human oral fibroblasts (NHOF) with and without ec- without the need for telomeric DNA or hTR (9), binds the topic expression of hTERT/telomerase. telomere repeat-binding proteins TRF1 (10) and TRF2 (11), and Experimental Design: To study the effect of hTERT/ is thought to regulate the access of telomerase to telomere DNA telomerase on DNA repair, we examined the mutation fre- ends (12, 13). -
Transcripts of the Adeno-Associated Virus Genome: Mapping of the Major Rnas MICHAEL R
JOURNAL OF VIROLOGY, Oct. 1980, p. 79-92 Vol. 36, No. 1 0022-538X/80/10-0079/14$02.00/0 Transcripts of the Adeno-Associated Virus Genome: Mapping of the Major RNAs MICHAEL R. GREEN AND ROBERT G. ROEDER Departments ofBiological Chemistry and Genetics, Division ofBiology and Biomedical Sciences, Washington University School ofMedicine, St. Louis, Missouri 63110 The four major adeno-associated virus type 2 (AAV2)-specific RNAs were mapped on the linear viral genome by a variety of biochemical techniques, including Si nuclease and exonuclease VII mapping, RNA gel-transfer hybridi- zation, and analysis of reverse transcriptase extension products. All the major AAV2 RNAs were derived from the minus DNA strand and had 3' termini at position 96. The nucleus-specific 4.3- and 3.6-kilobase (kb) RNAs had 5' termini at positions 6 and 19, respectively. The 5' terminus of the 2.6-kb RNA mapped to position 38.5. The predominant 2.3-kb AAV2 mRNA was spliced and contained a short leader sequence (approximately 50 nucleotides) which mapped to position 38.5, coincident with the 5' terminus of the 2.6-kb RNA. The 5' end of the body of the 2.3-kb RNA mapped to position 46.5. These results are discussed in terms of the involvement of single versus multiple promoters (for transcription) and RNA splicing mechanisms in the generation of the AAV2 RNAs. Mammalian DNA viruses have provided pow- In our earlier studies ofAAV2 (19), we defined erful models for the analysis and formulation of and partially characterized four predominant mechaisms of gene expression in eucaryotic AAV2 RNAs in virus-infected cells, indicating cells. -
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Characterization and evolution of artificial RNA ligases A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY Aleardo Morelli IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Adviser: Burckhard Seelig June 2015 © Aleardo Morelli, 2015 Abstract Enzymes enable biocatalysis with minimal by-products, high regio- and enantioselectivity, and can operate under mild conditions. These properties facilitate numerous applications of enzymes in both industry and research. Great progress has been made in protein engineering to modify properties such as stability and catalytic activity of an enzyme to suit specific processes. On the contrary, the generation of artificial enzymes de novo is still challenging, and only few examples have been reported. The study and characterization of artificial enzymes will not only expand our knowledge of protein chemistry and catalysis, but ultimately improve our ability to generate novel biocatalysts and engineer those found in nature. My thesis focused on the characterization of an artificial RNA ligase previously selected from a library of polypeptide variants based on a non-catalytic protein scaffold. The selection employed mRNA display, a technique to isolate de novo enzymes in vitro from large libraries of 1013 protein variants. The artificial RNA ligase catalyzes the formation of a phosphodiester bond between two RNA substrates by joining a 5'- triphospate to a 3'-hydroxyl, with the release of pyrophosphate. This activity has not been observed in nature. An initial selection carried out at 23°C yielded variants that were poorly suitable for biochemical and biophysical characterization due do their low solubility and poor folding. -
Ubc 2008 Spring Li Alice.Pdf
IDENTIFICATION OF VIRULENCE DETERMINANTS OF MYCOBACTERIUM TUBERCULOSIS VIA GENETIC COMPARISONS OF A VIRULENT AND AN ATTENUATED STRAIN OF MYCOBACTERIUM TUBERCULOSIS. by ALICE HOY LAM LI B.Sc., The University of British Columbia, 2001 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIRMENT FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES (Pathology) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) MARCH 2008 Alice Hoy Lam Li, 2008 i ABSTRACT Candidate virulence genes were sought through the genetic analyses of two strains of Mycobacterium tuberculosis, one virulent, H37Rv, one attenuated, H37Ra. Derived from the same parent, H37, genomic differences between strains were first examined via two-dimensional DNA technologies: two-dimensional bacterial genome display, and bacterial comparative genomic hybridisation. The two-dimensional technologies were optimised for mycobacterial use, but failed to yield reproducible genomic differences between the two strains. Expression differences between strains during their infection of murine bone-marrow-derived macrophages were then assessed using Bacterial Artificial Chromosome Fingerprint Arrays. This technique successfully identified expression differences between intracellular M. tuberculosis H37Ra and H37Rv, and six candidate genes were confirmed via quantitative real-time PCR for their differential expression at 168 hours post-infection. Genes identified to be upregulated in the attenuated H37Ra were frdB, frdC, and frdD. Genes upregulated in the virulent H37Rv were pks2, aceE, and Rv1571. Further qPCR analysis of these genes at 4 and 96h post-infection revealed that the frd operon (encoding for the fumarate reductase enzyme complex or FRD) was expressed at higher levels in the virulent H37Rv at earlier time points while the expression of aceE and pks2 was higher in the virulent strain throughout the course of infection. -
M1224-100 Thermostable Rnase H
BioVision 03/17 For research use only Thermostable RNAse H CATALOG NO.: M1224-100 10X THERMOSTABLE RNAse H REACTION BUFFER: 500 mM Tris-HCl, 1000 mM NaCl, AMOUNT: 500 U (100 µl) 100 mM MgCl2, pH 7.5 PRODUCT SOURCE: Recombinant E. coli REACTION CONDITIONS: Use 1X Thermostable RNAse H Reaction Buffer and incubate CONCENTRATION: 100 U/µl at a chosen temperature between 65°C and 95°C (enzyme half-life is 2 hours at 70°C and 30 minutes at 95°C). FORM: Liquid. Enzyme supplied with 10X Reaction Buffer COMPONENTS: Product Name Size Part. No. Thermostable RNAse H (5 U/μl) 100 µl M1224-100-1 10X Thermostable RNAse Reaction Buffer 500 µl M1224-100-2 DESCRIPTION: Thermostable RNAse H (Ribonuclease H) is an endoribonuclease that specifically hydrolyzes the phosphodiester bonds of RNA strands in RNA-DNA hybrids. Unlike E. coli RNAse H which is inactivated at temperatures above 55°C, Thermostable RNase H can withstand much higher temperatures. These higher temperatures allow for higher hybridization stringency for RNA-DNA heteroduplexes resulting in more specific hydrolysis of RNA. Thermostable RNase H has optimal activity above 65°C and is active up to 95°C making it useful for a broad range of applications. APPLICATIONS: 1. High-stringency hybrid selection and mapping of mRNA structure 2. Removal of mRNA prior to synthesis of second strand cDNA 3. Removal of the poly(A) sequences from mRNA in the presence of oligo (dT) 4. Directed cleavage of RNA RELATED PRODUCTS: STORAGE CONDITIONS: Store at -20°C. Avoid repeated freeze-thaw cycles of all E. -
Arthur Kornberg Discovered (The First) DNA Polymerase Four
Arthur Kornberg discovered (the first) DNA polymerase Using an “in vitro” system for DNA polymerase activity: 1. Grow E. coli 2. Break open cells 3. Prepare soluble extract 4. Fractionate extract to resolve different proteins from each other; repeat; repeat 5. Search for DNA polymerase activity using an biochemical assay: incorporate radioactive building blocks into DNA chains Four requirements of DNA-templated (DNA-dependent) DNA polymerases • single-stranded template • deoxyribonucleotides with 5’ triphosphate (dNTPs) • magnesium ions • annealed primer with 3’ OH Synthesis ONLY occurs in the 5’-3’ direction Fig 4-1 E. coli DNA polymerase I 5’-3’ polymerase activity Primer has a 3’-OH Incoming dNTP has a 5’ triphosphate Pyrophosphate (PP) is lost when dNMP adds to the chain E. coli DNA polymerase I: 3 separable enzyme activities in 3 protein domains 5’-3’ polymerase + 3’-5’ exonuclease = Klenow fragment N C 5’-3’ exonuclease Fig 4-3 E. coli DNA polymerase I 3’-5’ exonuclease Opposite polarity compared to polymerase: polymerase activity must stop to allow 3’-5’ exonuclease activity No dNTP can be re-made in reversed 3’-5’ direction: dNMP released by hydrolysis of phosphodiester backboneFig 4-4 Proof-reading (editing) of misincorporated 3’ dNMP by the 3’-5’ exonuclease Fidelity is accuracy of template-cognate dNTP selection. It depends on the polymerase active site structure and the balance of competing polymerase and exonuclease activities. A mismatch disfavors extension and favors the exonuclease.Fig 4-5 Superimposed structure of the Klenow fragment of DNA pol I with two different DNAs “Fingers” “Thumb” “Palm” red/orange helix: 3’ in red is elongating blue/cyan helix: 3’ in blue is getting edited Fig 4-6 E. -
Supplemental Methods
Supplemental Methods: Sample Collection Duplicate surface samples were collected from the Amazon River plume aboard the R/V Knorr in June 2010 (4 52.71’N, 51 21.59’W) during a period of high river discharge. The collection site (Station 10, 4° 52.71’N, 51° 21.59’W; S = 21.0; T = 29.6°C), located ~ 500 Km to the north of the Amazon River mouth, was characterized by the presence of coastal diatoms in the top 8 m of the water column. Sampling was conducted between 0700 and 0900 local time by gently impeller pumping (modified Rule 1800 submersible sump pump) surface water through 10 m of tygon tubing (3 cm) to the ship's deck where it then flowed through a 156 µm mesh into 20 L carboys. In the lab, cells were partitioned into two size fractions by sequential filtration (using a Masterflex peristaltic pump) of the pre-filtered seawater through a 2.0 µm pore-size, 142 mm diameter polycarbonate (PCTE) membrane filter (Sterlitech Corporation, Kent, CWA) and a 0.22 µm pore-size, 142 mm diameter Supor membrane filter (Pall, Port Washington, NY). Metagenomic and non-selective metatranscriptomic analyses were conducted on both pore-size filters; poly(A)-selected (eukaryote-dominated) metatranscriptomic analyses were conducted only on the larger pore-size filter (2.0 µm pore-size). All filters were immediately submerged in RNAlater (Applied Biosystems, Austin, TX) in sterile 50 mL conical tubes, incubated at room temperature overnight and then stored at -80oC until extraction. Filtration and stabilization of each sample was completed within 30 min of water collection. -
B Number Gene Name Mrna Intensity Mrna
sample) total list predicted B number Gene name assignment mRNA present mRNA intensity Gene description Protein detected - Membrane protein membrane sample detected (total list) Proteins detected - Functional category # of tryptic peptides # of tryptic peptides # of tryptic peptides detected (membrane b0002 thrA 13624 P 39 P 18 P(m) 2 aspartokinase I, homoserine dehydrogenase I Metabolism of small molecules b0003 thrB 6781 P 9 P 3 0 homoserine kinase Metabolism of small molecules b0004 thrC 15039 P 18 P 10 0 threonine synthase Metabolism of small molecules b0008 talB 20561 P 20 P 13 0 transaldolase B Metabolism of small molecules chaperone Hsp70; DNA biosynthesis; autoregulated heat shock b0014 dnaK 13283 P 32 P 23 0 proteins Cell processes b0015 dnaJ 4492 P 13 P 4 P(m) 1 chaperone with DnaK; heat shock protein Cell processes b0029 lytB 1331 P 16 P 2 0 control of stringent response; involved in penicillin tolerance Global functions b0032 carA 9312 P 14 P 8 0 carbamoyl-phosphate synthetase, glutamine (small) subunit Metabolism of small molecules b0033 carB 7656 P 48 P 17 0 carbamoyl-phosphate synthase large subunit Metabolism of small molecules b0048 folA 1588 P 7 P 1 0 dihydrofolate reductase type I; trimethoprim resistance Metabolism of small molecules peptidyl-prolyl cis-trans isomerase (PPIase), involved in maturation of b0053 surA 3825 P 19 P 4 P(m) 1 GenProt outer membrane proteins (1st module) Cell processes b0054 imp 2737 P 42 P 5 P(m) 5 GenProt organic solvent tolerance Cell processes b0071 leuD 4770 P 10 P 9 0 isopropylmalate -
Recd: the Gene for an Essential Third Subunit of Exonuclease V
Proc. Nati. Acad. Sci. USA Vol. 83, pp. 5558-5562, August 1986 Genetics recD: The gene for an essential third subunit of exonuclease V [genetic recombination/ceil viability/nudease-negative, recombination.-positive (recB*) phenotype/RecBCD enzyme] SUSAN K. AMUNDSEN*, ANDREW F. TAYLOR, ABDUL M. CHAUDHURYt, AND GERALD R. SMITH§ Fred Hutchinson Cancer Research Center, 1124 Columbia Street, Seattle, WA 98104 Communicated by Hamilton 0. Smith, February 24, 1986 ABSTRACT Exonuclease V (EC 3.1.11.5) of Escherichia The subunit composition of ExoV has been uncertain. coli, an enzyme with multiple activities promoting genetic Genetic complementation analysis of ExoV null mutants recombination, has previously been shown to contain two (those lacking any detectable activity) revealed two genes, polypeptides, the products of the recB and recC genes. We recB and recC (12). These genes code for two polypeptides report here that the enzyme contains in addition a third with approximate molecular masses of 120 and 110 kDa, polypeptide (a) with a molecular mass of about 58 kDa. The a respectively, seen in purified preparations of ExoV (8, 13, poypeptide is not synthesized by a class ofmutants (previously 14). ExoV can be dissociated by high salt and separated by designated recB*) lacking the nuclease activity of exonuclease column chromatography into two inactive fractions, desig- V but retaining recombination proficiency. The gene, recD, nated a and /; mixing a and f3 restores nuclease and ATPase coding for the a polypeptide is located near recB in the order activity (15, 16). Unexpectedly, a activity is present in thyA-recC-ptr-recB-recD-agA on the E. -
Supplementary Information Genomice and Transcriptomic Analysis
Supplementary Information Genomice and Transcriptomic Analysis for Identification of Genes and Interlinked Pathways Mediating Artemisinin Resistance in Leishmania donovani Sushmita Ghosh1,2, Aditya Verma1, Vinay Kumar1, Dibyabhaba Pradhan3, Angamuthu Selvapandiyan 2, Poonam Salotra1, Ruchi Singh1* 1. ICMR- National Institute of Pathology, Safdarjung Hospital Campus, New Delhi-110029, India 2. Jamia Hamdard University-Institute of Molecular Medicine, New Delhi-110062, India 3. ICMR-AIIMS Computational Genomics Centre, Indian Council of Medical Research, New Delhi- 110029 *Correspondence: [email protected] Supplementary Figures and Tables: Figure S1. Figure S1: Comparative transcriptional responses following ART adaptation in L. donovani. Overlap of log2 transformed K133 AS-R and K133 WT expression ratio plotted as a function of chromosomal location of probes representing the full genome microarray. The plot represents the average values of three independent hybridizations for each isolate. Table S1: List of genes validated for their modulated expression by Quantitative real time- PCR S.N Primer Gene Name/ Function/relevance Primer Sequence o. Name Gene ID 1 AQP1 Aquaglyceropor Metal ion F- in (LinJ.31.0030) transmembrane 5’CAGGGACAGCTCGAGGGTAA transporter activity, AA3’ integral to membrane; transmembrane R- transport; transporter 5’GTTACCGGCGTGAAAGACAG activity; water TG3’ transport. 2 A2 A2 protein Cellular response to F- (LinJ.22.0670) stress 5’GTTGGCCCGCTTTCTGTTGG3’ R- 5’ACCAACGTCAACAGAGAGA GGG3’ 3 ABCG1 ATP-binding ATP binding, ATPase -
Letters to Nature
letters to nature Received 7 July; accepted 21 September 1998. 26. Tronrud, D. E. Conjugate-direction minimization: an improved method for the re®nement of macromolecules. Acta Crystallogr. A 48, 912±916 (1992). 1. Dalbey, R. E., Lively, M. O., Bron, S. & van Dijl, J. M. The chemistry and enzymology of the type 1 27. Wolfe, P. B., Wickner, W. & Goodman, J. M. Sequence of the leader peptidase gene of Escherichia coli signal peptidases. Protein Sci. 6, 1129±1138 (1997). and the orientation of leader peptidase in the bacterial envelope. J. Biol. Chem. 258, 12073±12080 2. Kuo, D. W. et al. Escherichia coli leader peptidase: production of an active form lacking a requirement (1983). for detergent and development of peptide substrates. Arch. Biochem. Biophys. 303, 274±280 (1993). 28. Kraulis, P.G. Molscript: a program to produce both detailed and schematic plots of protein structures. 3. Tschantz, W. R. et al. Characterization of a soluble, catalytically active form of Escherichia coli leader J. Appl. Crystallogr. 24, 946±950 (1991). peptidase: requirement of detergent or phospholipid for optimal activity. Biochemistry 34, 3935±3941 29. Nicholls, A., Sharp, K. A. & Honig, B. Protein folding and association: insights from the interfacial and (1995). the thermodynamic properties of hydrocarbons. Proteins Struct. Funct. Genet. 11, 281±296 (1991). 4. Allsop, A. E. et al.inAnti-Infectives, Recent Advances in Chemistry and Structure-Activity Relationships 30. Meritt, E. A. & Bacon, D. J. Raster3D: photorealistic molecular graphics. Methods Enzymol. 277, 505± (eds Bently, P. H. & O'Hanlon, P. J.) 61±72 (R. Soc. Chem., Cambridge, 1997). -
The Response to DNA Damage at Telomeric Repeats and Its Consequences for Telomere Function
Review The Response to DNA Damage at Telomeric Repeats and Its Consequences for Telomere Function Ylli Doksani IFOM, The FIRC Institute of Molecular Oncology, via Adamello 16, 20139 Milan, Italy; [email protected]; Tel.: +39-02-574303258 Received: 26 March 2019; Accepted: 18 April 2019; Published: 24 April 2019 Abstract: Telomeric repeats, coated by the shelterin complex, prevent inappropriate activation of the DNA damage response at the ends of linear chromosomes. Shelterin has evolved distinct solutions to protect telomeres from different aspects of the DNA damage response. These solutions include formation of t-loops, which can sequester the chromosome terminus from DNA-end sensors and inhibition of key steps in the DNA damage response. While blocking the DNA damage response at chromosome ends, telomeres make wide use of many of its players to deal with exogenous damage and replication stress. This review focuses on the interplay between the end-protection functions and the response to DNA damage occurring inside the telomeric repeats, as well as on the consequences that telomere damage has on telomere structure and function. Keywords: telomere maintenance; shelterin complex; end-protection problem; telomere damage; telomeric double strand breaks; telomere replication; alternative lengthening of telomeres 1. Telomere Structure and End-Protection Functions Mammalian telomeres are made of tandem TTAGGG repeats that extend several kilobases and terminate with a 3′ single-stranded overhang about 50–400 nucleotides long. Telomeric repeats are coated in a sequence-specific fashion by a 6-protein complex named shelterin that prevents the activation of the Double Strand Break (DSB) response at chromosome ends [1-3].